Data Sheet

Freescale Semiconductor
Technical Data
Document Number: MC33742
Rev. 15.0, 12/2014
System Basis Chip with
Enhanced High Speed CAN
Transceiver
33742
33742S
SYSTEM BASIS CHIP
The 33742 and the 33742S SMARTMOS devices are SPI-controlled
System Basis Chips (SBCs), combining many frequently used functions,
along with a CAN 2.0-compliant transceiver, used in many automotive
electronic control units (ECUs). The 33742 SBC has a fully protected
fixed 5.0 V low dropout internal regulator, with current limiting,
overtemperature prewarning, and reset. A second 5.0 V regulator can be
implemented using external pass PNP bipolar junction pass transistor,
driven by the SBC’s external V2 sense input and V2 output drive pins.
The SBC has four main operating modes: Normal, Standby, Stop, and
Sleep mode. Additionally, there is an internally switched high side power
supply output, four wake-up inputs pins, a programmable window
watchdog, interrupt, reset, and a SPI module for communication and
control. The high speed CAN A and B transceiver is available for
intermodule communication.
EG SUFFIX (PB-FREE)
98ASB42345B
28-PIN SOICW
EP SUFFIX
(PB-FREE)
98ASA00757D
48-PIN QFN
ORDERING INFORMATION
Device
Features
• 1.0 Mbps CAN transceiver bus interface with bus diagnostic capability
• SPI control at frequencies up to 4.0 MHz
• 5.0 V low dropout voltage regulator with current limiting, overtemperature prewarning, and output monitoring and reset
• A second 5.0 V regulator capability using an external series pass
transistor
• Normal, Standby, Stop, and Sleep modes of operation with low Sleep
and Stop mode current
• A high side switch output driver for controlling external circuitry
Temperature
Range (TA)
MC33742PEG/R2
MC33742SPEG/R2
- 40 °C to 125 °C
MC33742PEP/R2
VPWR
MCU
CS
SCLK
MOSI
MISO
SPI
VDD
VSUP
RST
V2CTRL
V2
CS
SCLK
MOSI
L0
L1
L2
MISO
L3
WDOG
INT
TXD
GND
RXD
HS
CANH
CANL
GND
V2
VPWR
Safe
Circuitry
ECU Local
Circuitry
Twisted
Pair
CAN Bus
Figure 1. 33742 Simplified Application Diagram
© Freescale Semiconductor, Inc., 2007-2014. All rights reserved.
28 SOICW
48 QFN
33742
5.0V
Package
DEVICE VARIATIONS
DEVICE VARIATIONS
Table 1. Device Differences During a Reset Condition
Part No.
Reset Duration
Device Differences
See Page
33742
15 ms (typical)
The duration the RST pin is asserted low when the Reset mode is entered after
the SBC is powered up, a VDD under-voltage condition is detected, and the
watchdog register is not properly triggered.
page 18
33742S
3.5 ms (typical)
The duration the RST pin is asserted low when the Reset mode is entered after
the SBC is powered up, a VDD under-voltage condition is detected, and the
watchdog register is not properly triggered.
page 18
33742
2
Analog Integrated Circuit Device Data
Freescale Semiconductor
INTERNAL BLOCK DIAGRAM
INTERNAL BLOCK DIAGRAM
V2CTRL
V2
VSUP Monitor
Dual Voltage Regulator
VSUP
V1 Monitor
HS Control
5.0V/200mA
V1
Mode Control
Oscillator
HS
Interrupt
Watchdog
Reset
L1
Programmable
Wake-up Input
L2
INT
WDOG
RST
MOSI
SPI
L3
SCLK
MISO
CS
L4
High-speed
1.0 Mbps
CAN Physical
Interface
CANH
CANL
TXD
RXD
GND
Figure 2. 33742 Simplified Internal Block Diagram
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
3
PIN CONNECTIONS
PIN CONNECTIONS
RXD
TXD
VDD
1
28
2
27
3
26
RST
INT
4
25
5
24
GND
GND
GND
GND
V2
V2CTRL
VSUP
HS
L0
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
WDOG
CS
MOSI
MISO
SCLK
GND
GND
GND
GND
CANL
CANH
L3
L2
L1
Figure 3. 33742 28-Pin Connections
Table 2. 33742 28-Pin Definitions
A functional description of each pin can be found in the Functional Pin description section beginning on page 22.
Pin
Pin Name
Formal Name
Definition
1
RXD
Receive Data
CAN bus receive data output pin.
2
TXD
Transmit Data
CAN bus transmit data input pin.
3
VDD
Voltage Digital Drain
4
RST
Reset Output
(Active LOW)
5.0 V regulator output pin. Supply pin for the MCU.
This is the device reset output pin whose main function is to reset the MCU. This pin has
an internal
-up current source to VDD.
5
INT
Interrupt Output
(Active LOW)
This output is asserted LOW when an enabled interrupt condition occurs. The output is
a push-pull structure.
6–9
20 – 23
GND
Ground
These device ground pins are internally connected to the package lead frame to provide
a 33742-to-PCB thermal path.
10
V2
Voltage Source 2
Sense input for the V2 regulator using an external series pass transistor. V2 is also the
internal supply for the CAN transceiver.
11
V2CTRL
Voltage Source 2 Control
Output drive source for the V2 regulator connected to the external series pass transistor.
12
VSUP
Voltage Supply
13
HS
High Side Output
Output of the internal high side switch. The output current is internally limited to 150 mA.
14 –17
L0- L3
Level 0 - 3 Inputs
Inputs from external switches or from logic circuitry.
18
CANH
CAN High Output
CAN high output pin.
19
CANL
CAN Low Output
CAN low output pin.
24
SCLK
Serial Data Clock
Clock input pin for the Serial Peripheral Interface (SPI).
25
MISO
Master In Slave Out
SPI data sent to the MCU by the 33742. When CS is HIGH, the pin is in the highimpedance state.
26
MOSI
Master Out Slave In
SPI data received by the 33742.
27
CS
Chip Select
(Active LOW)
28
WDOG
Watchdog Output
(Active LOW)
Supply input pin for the 33742.
The CS input pin is used with the SPI bus to select the 33742. When the CS is asserted
LOW, the 33742 is the selected device of the SPI bus.
The WDOG output pin is asserted LOW if the software watchdog is not correctly
triggered.
33742
4
Analog Integrated Circuit Device Data
Freescale Semiconductor
48
47
46
45
44
43
42
41
40
39
38
37
NC
NC
NC
NC
GND
GND
GND
GND
NC
NC
NC
NC
PIN CONNECTIONS
Transparent
Top View
NC
SCLK
MISO
MOSI
CS
WDOG
RXD
NC
CANL
CANH
L3
L2
L1
L0
HS
VSUP
V2 CTRL
V2
NC
NC
NC
NC
NC
GND
GND
GND
GND
NC
NC
NC
NC
13
14
15
16
17
18
19
20
21
22
23
24
TXD
VDD
RST
INT
NC
36
35
34
33
32
31
30
29
28
27
26
25
1
2
3
4
5
6
7
8
9
10
11
12
Figure 4. 33742 48-Pin Connections
Table 3. 33742 48-Pin Definitions
A functional description of each pin can be found in the Functional Pin description section beginning on page 22.
Pin
Pin Name
Formal Name
Definition
1, 12-16,
21-25,
36-40,
45-48
NC
No Connect
2
SCLK
Serial Data Clock
3
MISO
Master In Slave Out
SPI data sent to the MCU by the 33742. When CS is HIGH, the pin is in the highimpedance state.
4
MOSI
Master Out Slave In
SPI data received by the 33742.
5
CS
Chip Select
(Active LOW)
6
WDOG
Watchdog Output
(Active LOW)
7
RXD
Receive Data
CAN bus receive data output pin.
8
TXD
Transmit Data
CAN bus transmit data input pin.
9
VDD
Voltage Digital Drain
10
RST
Reset Output
(Active LOW)
This is the device reset output pin whose main function is to reset the MCU. This pin has
an internal pull-up current source to VDD.
11
INT
Interrupt Output
(Active LOW)
This output is asserted LOW when an enabled interrupt condition occurs. The output is
a push-pull structure.
17-20
41-44
GND
Ground
These device ground pins are internally connected to the package lead frame to provide
a 33742-to-PCB thermal path.
No connection.
Clock input pin for the Serial Peripheral Interface (SPI).
The CS input pin is used with the SPI bus to select the 33742. When the CS is asserted
LOW, the 33742 is the selected device of the SPI bus.
The WDOG output pin is asserted LOW if the software watchdog is not correctly
triggered.
5.0 V regulator output pin. Supply pin for the MCU.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
5
PIN CONNECTIONS
Table 3. 33742 48-Pin Definitions (continued)
A functional description of each pin can be found in the Functional Pin description section beginning on page 22.
Pin
Pin Name
Formal Name
Definition
26
V2
Voltage Source 2
Sense input for the V2 regulator using an external series pass transistor. V2 is also the
internal supply for the CAN transceiver.
27
V2CTRL
Voltage Source 2 Control
28
VSUP
Voltage Supply
29
HS
High Side Output
Output of the internal high side switch. The output current is internally limited to 150 mA.
30-33
L0- L3
Level 0 - 3 Inputs
Inputs from external switches or from logic circuitry.
34
CANH
CAN High Output
CAN high output pin.
35
CANL
CAN Low Output
CAN low output pin.
Output drive source for the V2 regulator connected to the external series pass
transistor.
Supply input pin for the 33742.
33742
6
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
MAXIMUM RATINGS
ELECTRICAL CHARACTERISTICS
MAXIMUM RATINGS
Table 4. Maximum Ratings
All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or
permanent damage to the device.
Rating
Symbol
Value
Unit
ELECTRICAL RATINGS
Power Supply Voltage at VSUP
VSUP
V
Continuous (Steady-state)
- 0.3 to 27
Transient Voltage (Load Dump)
- 0.3 to 40
Logic Signals 
(RXD, TXD, MOSI, MISO, CS, SCLK, RST, WDOG, and INT)
VLOG
- 0.3 to VDD + 0.3
V
Output Voltage at VDD
VDD
0.0 to 5.3
V
Output Current at VDD
IDD
Internally Limited
A
Voltage
VHS
- 0.3 to VSUP + 0.3
V
Output Current
IHS
Internally Limited
A
HS
ESD Capability, Human Body Model(1)
VESD1
V
MC33742 in 28-pin SOIC
HS, L0, L1, L2, L3, CANH, CANL pins
± 4000
All Other pins
± 2000
MC33742 in 48-pin QFN
All pins
± 2000
(1)
ESD Capability, Machine Model
VESD2
± 200
V
DC Input Voltage
VDCIN
- 0.3 to 40
V
DC Input Current
IDCIN
± 2.0
mA
VTRINEC
± 100
V
Continuous Voltage
VCANH/L
- 27 to 40
V
Continuous Current
ICANH/L
200
mA
VLDH/L
40
V
VTRH/L
± 40
V
Input Voltage/Current at L0, L1, L2, L3
Transient Input Voltage attached to external circuitry(2)
CANL and CANH
CANH and CANL Transient Voltage (Load Dump)(3)
CANH and CANL Transient Voltage
(3)
Notes
1. Testing done in accordance with the Human Body Model (CZAP = 100 pF, RZAP = 1500 ), Machine Model (CZAP = 200 pF, RZAP = 0 ).
2.
3.
Testing done in accordance with ISO 7637-1. See Figure 5.
Load dump testing done in accordance with ISO 7637-1, Transient test done in accordance with ISO 7637-1. See Figure 6.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
7
ELECTRICAL CHARACTERISTICS
MAXIMUM RATINGS
Table 4. Maximum Ratings (continued)
All voltages are with respect to ground unless otherwise noted. Exceeding these ratings may cause a malfunction or
permanent damage to the device.
Rating
Symbol
Value
Unit
Ambient
TA
- 40 to 125
Junction
TJ
- 40 to 150
Storage Temperature
TSTG
- 55 to 165
C
Thermal Resistance
RJG
20
C/W
RTJC-RJC
TBD
C/W
PD
1.0
W
TPPRT
Note 7
°C
THERMAL RATINGS
Operating Temperature
C
Thermal Resistance Junction Case (QFN)
Power
Dissipation(4)
(6) (7)
Peak Package Reflow Temperature During Reflow ,
Notes
4. Maximum power dissipation is at 85 °C ambient temperature in free aIr and with no heatsink, according to JEDEC JESD51-2 and
JESD51-3 specifications.
5. The package is not designed for immersion soldering. The maximum soldering time is 10 seconds at 240 C on any pin. Exceeding the
maximum temperature and time limits may cause permanent damage to the device.
6. Pin soldering temperature limit is for 10 seconds maximum duration. Not designed for immersion soldering. Exceeding these limits may
cause malfunction or permanent damage to the device.
7. Freescale’s Package Reflow capability meets Pb-free requirements for JEDEC standard J-STD-020C. For Peak Package Reflow
Temperature and Moisture Sensitivity Levels (MSL), Go to www.freescale.com, search by part number [e.g. remove prefixes/suffixes
and enter the core ID to view all orderable parts. (i.e. MC33xxxD enter 33xxx), and review parametrics.
33742
1.0 nF
Lx
10 k
GND
Transient Pulse
Generator
(Note)
GND
Note Waveform per ISO 7637-1. Test Pulses 1, 2, 3a, and 3b.
Figure 5. Transient Test Setup for L0 : L3 Inputs
33742
1.0 nF
CANH
Transient Pulse
Generator
(Note)
CANL
GND
1.0 nF
GND
Note Waveform per ISO 7637-1. Test Pulses 1, 2, 3a, and 3b.
Figure 6. Transient Test Setup for CANH / CANL
33742
8
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
5.5
—
18
18
—
27
Extended DC Voltage: Reduced Functionality
4.5
—
5.5
Load Dump
—
—
40
Jump Start
—
—
27
Unit
INPUT PIN (VSUP)
Supply Voltage
VSUP
Nominal DC Voltage
Extended DC Voltage: Full Functionality(8)
(9)
(10)
Supply Current in Standby Mode

(IOUT at VDD = 40 mA, CAN Recessive or Sleep Mode)
V
ISUP(STDBY)
TA  25 C
mA
—
Mode(10)
Supply Current in Normal

(IOUT at VDD = 40 mA, CAN Recessive or Sleep mode)
mA
—
Supply Current in Sleep
(VDD and V2 OFF, CAN in Sleep Mode with CAN Wake-up Disabled(11))
45
ISUP(NORM)
TA  25 C
Mode(10)
42
42
45
A
ISUP(SLP-WD)
VSUP < 13.5 V, Oscillator Running(12)
—
85
105
VSUP < 13.5 V, Oscillator Not Running(13)
—
53
80
—
110
140
VSUP = 18 V, Oscillator Running(12)
Supply Current in Sleep Mode(10) 
(V1 and V2 OFF, VSUP < 13.5 V, Oscillator Not Running(13), CAN in Sleep
Mode with Wake-up Enabled)
TA = - 40 C
TA = 25 C
TA = 125 C
Mode(10)
Supply Current in Stop

(IOUT at VDD < 2.0 mA, VDD ON, CAN in Sleep Mode with Wake-up
Disabled(11))
VSUP < 13.5 V, Oscillator Running(12)
VSUP < 13.5 V, Oscillator Not Running(13)
VSUP = 18 V, Oscillator Running(12)
A
ISUP(SLP-WE)
—
80
—
—
65
—
—
55
—
A
ISUP(STOP-WD)
—
—
160
—
80
160
—
100
210
Notes
8. All functions and modes available and operating: Watchdog, HS turn ON / turn OFF, CAN transceiver operating, L0 : L3 inputs operating,
normal SPI operation. The 33742 may experience an over-temperature fault.
9. At VDD > 4.0 V, RST HIGH if reset 2 selected via SPI. The logic HIGH level will be degraded but the 33742 is functional.
10. Current measured at the VSUP pin.
11. If CAN Module is Sleep-enabled for wake-up, an additional current (ICAN-SLEEP) must be added to specified value.
12.
13.
Oscillator running means one of the following function is active: Forced Wake-up or Cyclic Sense or Software Watchdog in Stop mode.
Oscillator not running means none of the following functions are active: Forced Wake-up and Cyclic Sense and Software Watchdog in
Stop mode.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
9
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
INPUT PIN (VSUP) (CONTINUED)
Supply Current in Stop Mode(14) 
( IOUT at VDD < 2.0 mA, VDD ON, VSUP < 13.5 V, Oscillator Not Running,
CAN in Sleep Mode with Wake-up Enabled)(15)
A
ISUP(STOP-WE)
TA = - 40 C
—
100
—
—
92
—
—
80
—
VBF
1.5
3.0
4.0
V
BATFAIL Flag Hysteresis
VBF(HYS)
—
1.0
—
V
Battery Fall Early Warning Threshold
VBF(EW)
TA = 25 C
TA = 125 C
BATFAIL Flag Internal Threshold
(16)
In Normal and Standby Modes
V
5.3
5.8
6.3
0.1
0.2
0.3
5.5 V < VSUP < 27 V
4.9
5.0
5.1
4.5 V < VSUP < 5.5 V
4.0
—
—
—
0.2
0.5
—
0.1
0.25
Battery Fall Early Warning Hysteresis
VBF(EW-HYST)
In Normal and Standby Modes(16)
V
OUTPUT PIN (VDD)(17)
VDD Output Voltage (2.0 mA < IV1 < 200 mA)
Dropout Voltage
VDDOUT
VDDDRP1
IDD = 200 mA
Dropout Voltage, Limited Output Current and Low VSUP
VDDTEMP Bit Set
mA
200
285
350
160
—
200
125
—
160
TSD
Normal or Standby Mode
Over-temperature Pre-warning (Junction)
V
IDD
Internally Limited
Thermal Shutdown (Junction)
V
VDDDRP2
IDD = 50 mA, 4.5 V < VSUP
Output Current
V
°C
TPW
°C
Notes
14. Current measured at the VSUP pin.
15. Oscillator not running means none of the following functions are active: Forced Wake-up and Cyclic Sense and Software Watchdog in
Stop mode.
16. Guaranteed by design; it is not production tested.
17. IDD is the total regulator output current. V1 specification with external capacitor. Stability requirement: Capacitance > 47 F, ESR < 1.3 
(tantalum capacitor). In Reset, Normal Request, Normal and Standby modes. Measures with capacitance = 47 F tantalum.
33742
10
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
TSD - TPW
20
—
40
°C
Threshold 1, Default Value after Reset, RSTTH Bit Set to Logic [0]
4.5
4.6
4.7
Threshold 2, RSTTH Bit Set to Logic [1]
4.0
4.2
4.3
1.0
—
VRSTTH
9.0 V < VSUP < 18 V
—
5.0
25
5.5 V < VSUP < 27 V
—
10
25
—
25
75
—
30
50
IDD  2.0 mA
4.75
5.0
5.25
IDD  10 mA
4.75
5.0
5.25
10
17
25
Threshold 1, Default Value after Reset, RSTTH Bit Set to Logic [0]
4.5
4.6
4.7
Threshold 2, RSTTH Bit Set to Logic [1]
4.1
4.2
4.3
—
5.0
25
—
15
75
OUTPUT PIN (VDD) (CONTINUED)(18)
Temperature Threshold Difference
Reset Threshold
VRSTTH
VDD for Reset Active
VDDR
Line Regulation (IDD = 10 mA, Capacitance = 47 F Tantalum at VDD)
VDDR
Load Regulation (Capacitance = 47 F Tantalum at V1)
VSUP = 13.5 V, IDD = 100
mV
VTHERM-S
mA(19)
V
mV
VLD
1.0 mA < IDD < 200 mA
Thermal Stability
V
mV
OUTPUT PIN IN STOP MODE (VDD)(18)
VDD Output Voltage
IDD Output Current to Wake-up
Reset Threshold(18)
Line Regulation (Capacitance = 47 F Tantalum at VDD)
VDDSTOP
IDDS-WU
VRST-STOP
1.0 mA < IDD < 10 mA
mA
V
VLR-STOP
5.5 V < VSUP < 27 V, IDD = 2.0 mA
Load Regulation (Capacitance = 47 F Tantalum at V1)
V
mV
VLD-STOP
mV
Notes
18. IDD is the total regulator output current. VDD specification with external capacitor. Stability requirement: capacitance > 47 F,
ESR < 1.3  (tantalum capacitor). In Reset, Normal Request, Normal and Standby modes, measures with capacitance = 47 F
tantalum.Selectable by RSTTH bit in SPI Register Reset Control Register (RCR).
19. Guaranteed by characterization and design; it is not production tested.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
11
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
0.99
1.0
1.01
200
—
—
0.0
—
10
3.75
4.0
4.25
0.0
—
1.0
VDD - 0.9
—
VDD
- 2.0
—
2.0
Unit
TRACKING VOLTAGE REGULATOR (V2)(20)
V2 Output Voltage (Capacitance = 10 F Tantalum at V2)
V2
2.0 mA  IV2  200 mA, 5.5 V < VSUP < 27 V
IV2 Output Current (for Information Only)
IV2
Depending on External Ballast Transistor
V2 Control Drive Current Capability(21)
mA
IV2CTRL
Worst Case at TJ = 125 °C
V2LOW Flag Threshold
VDD
V2LTH
mA
V
(22)
LOGIC OUTPUT PIN (MISO)
Low-level Output Voltage
VOL
IOUT = 1.5 mA
High-level Output Voltage
VOH
IOUT = -250 A
Tri-stated MISO Leakage Current
V
V
A
IHZ
0 V < VMISO < VDD
LOGIC INPUT PINS (MOSI, SCLK, CS)
High-level Input Voltage
VIH
0.7 VDD
—
VDD + 0.3
V
Low-level Input Voltage
VIL
- 0.3
—
0.3 VDD
V
High-level Input Current on CS
I IH
-100
—
- 20
-100
—
- 20
VIN = 4.0 V
Low-level Input Current on CS
A
I IL
VIN = 1.0 V
MOSI and SCLK Input Current
A
A
I IN
0 V < VIN < VDD
-10
—
10
- 300
- 250
-150
IO = 1.5 mA, 5.5 V < VSUP < 27 V
0.0
—
0.9
IO = 0 mA, 1.0 V <VSUP < 5.5 V
0.0
—
0.9
2.3
—
5.0
OUTPUT PIN
(RST)(23)
High-level Output Current
Low-level Output Voltage
RST Pull-down Current
V > 0.9 V
A
IOH
0 V < VOUT < 0.7 VDD
VOL
V
IPDW
mA
Notes
20. V2 specification with external capacitor. Stability requirement: capacitance > 42 F and ESR < 1.3  (tantalum capacitor), external
resistor between base and emitter required. Measurement conditions: ballast transistor MJD32C, capacitance > 10 F tantalum, 2.2 k
resistor between base and emitter of ballast transistor.
21. The guaranteed V2CTRL current capability is 10 mA. No active current limiting is used so the actual available current may be higher.
22. Push-pull structure with tri-state condition (CS HIGH).
23. Output pin only. Supply from VDD. Structure switch to ground with pull-up current source.
33742
12
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
0.0
—
0.9
VDD - 0.9
—
VDD
0.0
—
0.9
VDD - 0.9
—
VDD
TA = 25 °C, IOUT - 150 mA, VSUP > 9.0 V
—
2.0
2.5
TA = 125 °C, IOUT - 150 mA, VSUP > 9.0 V
—
—
4.5
TA = 125 °C, IOUT - 120 mA, 5.5 V < VSUP < 9.0 V
—
3.5
5.5
160
—
500
TSD
155
—
190
°C
ILEAK
—
—
10
A
-1.5
—
- 0.3
5.5 V < VSUP < 6.0 V
2.0
2.5
3.0
6.0 V < VSUP < 18 V
2.5
3.0
3.6
18 V < VSUP < 27 V
2.7
3.2
3.7
5.5 V < VSUP < 6.0 V
2.7
3.3
3.8
6.0 V < VSUP < 18 V
3.0
4.0
4.6
18 V < VSUP < 27 V
3.5
4.2
4.7
OUTPUT PIN (WDOG)(24)
Low-level Output Voltage
VOL
IO = 1.5 mA, 1.0 V < VSUP < 27 V
High-level Output Voltage
V
VOH
IO = -250 A
V
OUTPUT PIN (INT)(24)
Low-level Output Voltage
VOL
IO = 1.5 mA
High-level Output Voltage
V
VOH
IO = -250 A
V
OUTPUT PIN (HS)
Driver Output ON Resistance
Output Current Limitation
ILIM
VSUP - VHS > 1.0 V
HS Thermal Shutdown
HS Leakage Current
Output Clamp Voltage

RDS(ON)
mA
VCL
IOUT = -10 mA, No Inductive Load Drive Capability
V
INPUT PINS (L0, L1, L2, AND L3)
Low-voltage Detection Threshold
High-voltage Detection Threshold
Hysteresis
VTHL
VTHH
- 0.2 V < VIN < 40 V
V
VHYS
5.5 V < VSUP < 27 V
Input Current
V
V
0.6
—
1.3
-10
—
10
A
I IN
Notes
24. Push-pull structure.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
13
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
CAN in Normal mode, Bus Recessive State
IRES
—
1.3
3.0
mA
CAN in Normal mode, Bus Dominant State without Bus Load
IDOM
—
1.5
3.5
mA
ICAN-SLEEP
—
12
24
A
IDIS
—
—
1.0
A
VCM
- 27
—
40
V
CAN TRANSCEIVER CURRENT
Supply Current of CAN Module
CAN in Sleep State, Wake-up Enabled, V2 Regulator OFF
CAN in Sleep State, Wake-up Disabled, V2 Regulator OFF(25)
PINS (CANH AND CANL)
Bus Pin Common Mode Voltage
Differential Input Voltage (Common Mode Between - 3.0 V and 7.0 V)
VCANH - VCANL
mV
Recessive State at RXD
—
—
500
Dominant State at RXD
900
—
—
100
—
—
28-pin SOIC
5.0
—
100
48-pin QFN
5.0
—
50
10
—
100
Differential Input Hysteresis (RXD)
Input Resistance
VHYS
RIN
Differential Input Resistance
RIND
CANH Output Voltage
mV
k
VCANH
k
V
TXD Dominant State
2.75
—
4.5
TXD Recessive State
—
—
3.0
TXD Dominant State
0.5
—
2.25
TXD Recessive State
2.0
—
—
TXD Dominant State
1.5
—
3.0
V
TXD Recessive State
—
—
100
mV
CANL Output Voltage
VCANL
Differential Output Voltage
V
VoH - VoL
Output Current Capability (Dominant State)
mA
CANH
ICANH
—
—
- 35
CANL
ICANL
35
—
—
TSD
160
180
—
Over-temperature Shutdown
(26)
CANL Over-current Detection
mA
CANL
ICANL /OC
60
—
200
CANH
ICANH /OC
- 200
—
- 60
CANH and CANL Input Current, Device Supplied 
(CAN Sleep mode with CAN Wake-up Enabled or Disabled)
°C
A
ICAN1
VCANH, VCANL from 0 V to 5.0 V
—
3.0
VCANH, VCANL = - 2.0 V
- 60
- 50
—
VCANH, VCANL = 7.0 V
—
60
75
10
Notes
25. Guaranteed by design; it is not production tested.
26. Reported in CAN register. For a description of the contents of the CAN register, refer to CAN Register (CAN) on page 49
33742
14
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
STATIC ELECTRICAL CHARACTERISTICS
Table 5. Static Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
VCANH, VCANL = 2.5 V
—
40
100
VCANH, VCANL = - 2.0 V
- 60
- 50
—
VCANH, VCANL = 7.0 V
—
190
240
Unit
PINS (CANH AND CANL) (CONTINUED)
CANH and CANL Input Current, Device Unsupplied
A
ICAN2
DIAGNOSTIC INFORMATION (CANH AND CANL)
CANL to GND Threshold
VLG
—
1.75
—
V
CANH to GND Threshold
VHG
—
1.75
—
V
CANL to VSUP Threshold
VLVB
—
VSUP - 2.0
—
V
CANH to VSUP Threshold
VHVB
—
VSUP - 2.0
—
V
VL5
—
VDD - 0.43
—
V
VH5
—
VDD - 0.43
—
V
—
100
—
CANL to VDD Threshold
CANH to VDD Threshold
RXD Weak Pull-down Current
Source(27)
A
IRXDW
RXD Permanent Dominant Failure Condition
PINS (TXD AND RXD)
TXD Input High-voltage
VIH
0.7 VDD
—
VDD + 0.4
V
TXD Input Low-voltage
VIL
- 0.4
—
0.3 VDD
V
TXD High-level Input Current
IIH
VTXD = V2
TXD Low-level Input Current
IRXD = 1.0 mA
—
10
-150
- 100
- 50
A
VOH
IRXD = 250 A
RXD Output Low-voltage
-10
IIL
VTXD = 0 V
RXD Output High Voltage(28)
A
V
VDD - 1.0
—
—
—
—
0.5
VOL
V
Notes
27. Guaranteed by design; it is not production tested.
28. RXD is a push-pull structure between the V2 pin and GND.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
15
ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
Table 6. Dynamic Electrical Characteristics
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
SPI Operation Frequency
f REQ
0.25
—
4.0
MHz
SCLK Clock Period
t PCLK
250
—
N/A
ns
SCLK Clock High Time
t WSCLKH
125
—
N/A
ns
SCLK Clock Low Time
t WSCLKL
125
—
N/A
ns
Falling Edge of CS to Rising Edge of SCLK
t LEAD
100
—
N/A
ns
Falling Edge of SCLK to Rising Edge of CS
t LAG
100
—
N/A
ns
MOSI to Falling Edge of SCLK
t SISU
40
—
N/A
ns
Falling Edge of SCLK to MOSI
t SIH
40
—
N/A
ns
Time(30)
t RSO
DIGITAL INTERFACE TIMING (SCLK, CS, MOSI, MISO)(29)
MISO Rise
CL = 220 pF
(30)
MISO Fall Time
ns
—
25
50
—
25
50
—
—
50
—
—
50
t FSO
CL = 220 pF
ns
Time from Falling or Rising Edges of CS
MISO Low-impedance
MISO High-impedance
Time from Rising Edge of SCLK to MISO Data Valid
ns
t SOEN
t SODIS
t VALID
0.2 VDD  MISO  0.8 VDD, CL = 200 pF
ns
—
—
50
18
—
34
7.0
10
13
—
100
—
STATE MACHINE TIMING (CS, SCLK, MOSI, MISO, WDOG, INT)
Delay Between CS LOW-to-HIGH Transition (at End of SPI Stop Command)
and Stop mode Activation(31)
Interrupt Low-level Duration
t CS-STOP
t INT
Stop Mode
Internal Oscillator Frequency(32)
Notes
29.
30.
31.
32.
s
f OSC
s
kHz
See Figure 7, SPI Timing Diagram, page 20.
Not production tested. Guaranteed by design.
Not production tested. Guaranteed by design. Detected by V2 OFF.
f OSC is indirectly measured (1.0 ms reset) and trimmed.
33742
16
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
Table 6. Dynamic Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
STATE MACHINE TIMING (CS, SCLK, MOSI, MISO, WDOG, INT) (CONTINUED)
Watchdog Period Normal and Standby Modes
t WDOG
ms
28-pin SOIC
Period 1
8.58
9.75
10.92
Period 2
39.6
45
50.4
Period 3
88
100
112
308
350
392
8.3
9.75
10.92
38.5
45
50.4
86
100
112
300
350
392
28-pin SOIC
308
350
392
48-pin QFN
300
350
392
Period 1
6.82
9.75
12.7
Period 2
31.5
45
58.5
Period 3
70
100
130
Period 4
245
350
455
Normal and Standby Modes
-12
—
12
Stop Mode
- 30
—
30
Timing 1
3.22
4.6
5.98
Timing 2
6.47
9.25
12
Timing 3
12.9
18.5
24
Timing 4
25.9
37
48.1
Timing 5
51.8
74
96.2
Timing 6
66.8
95.5
124
Timing 7
134
191
248
Timing 8
271
388
504
Period 4
48-pin QFN
Period 1
Period 2
Period 3
Period 4
Normal Request Mode Timeout
Watchdog Period Stop Mode
Watchdog Period Accuracy
Cyclic Sense / FWU Timing Sleep and Stop Modes
Cyclic Sense ON Time
t NRTOUT
t WD-STOP
Sleep and Stop modes
ms
t ACC
%
t CSFWU
ms
t ON
Sleep and Stop modes.
Cyclic Sense / FWU Timing Accuracy
ms
s
200
350
500
- 30
—
30
t ACC
%
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
17
ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
Table 6. Dynamic Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
—
—
Max
Unit
STATE MACHINE TIMING (CS, SCLK, MOSI, MISO, WDOG, INT) (CONTINUED)
Delay Between SPI Command and HS Turn ON(33)
t S-HSON
Delay Between SPI Command and HS Turn OFF(33)
t S-HSOFF
—
22
t S-V2ON
s
9.0
Standby mode
Delay Between SPI and V2 Turn OFF(33)
22
s
9.0
Command(33)
—
t S-V2OFF
Normal mode
Delay Between Normal Request and Normal mode After Watchdog Trigger
s
—
Normal or Standby mode, VSUP > 9.0 V
Delay Between SPI and V2 Turn ON(33)
s
22
Normal or Standby mode, VSUP > 9.0 V
—
22
t S-NR2N
s
15
Normal Request mode
35
70
STATE MACHINE TIMING (CS, SCLK, MOSI, MISO, WDOG, INT) (CONTINUED)
Delay Between SPI and CAN Normal mode(34)
t S-CAN_N
Normal mode(35)
Delay Between SPI and CAN Sleep Mode(34)
Normal mode
—
—
10
s
s
40
90
t W-SPI
s
90
—
N/A
20
—
N/A
25
—
—
4.0
—
30
40
55
75
t S-1STSPI
Device in Stop mode After Wake-up
Delay Between Two SPI Messages Addressing the Same Register
10
15
Device in Stop mode After Wake-up
Delay Between INT Pulse and First SPI Command Accepted
—
t W-CS
Stop mode
Delay Between CS Wake-up (CS LOW to HIGH) and First Accepted SPI
Command
—
t S-CAN_S
(35)
Delay Between CS Wake-up (CS LOW to HIGH) and Device in Normal
Request mode (VDD ON and RST HIGH)
s
t 2SPI
s
s
OUTPUT PIN (VDD)
Reset Delay Time
IDD Over-current to Wake-up Deglitcher Time(35)
s
tD
Measured at 50% of Reset Signal
tIDD-DGLT
s
Notes
33. Delay starts at falling edge of clock cycle #8 of the SPI command and start of “Turn ON” or “Turn OFF” of HS or V2.
34. Delay starts at falling edge of clock cycle #8 of the SPI command and start of “Turn ON” or “Turn OFF” of HS or V2.
35. Guaranteed by design; it is not production tested.
33742
18
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
DYNAMIC ELECTRICAL CHARACTERISTICS
Table 6. Dynamic Electrical Characteristics (continued)
Characteristics noted under conditions 4.75 V  V2  5.25 V, 5.5 V  VSUP  18 V, and -40 C  TA  125 C. Typical values
noted reflect the approximate parameter mean at TA = 25 C under nominal conditions, unless otherwise noted.
Characteristic
Symbol
Min
Typ
Max
Unit
OUTPUT PIN (RST)
Reset Duration After VDD HIGH
ms
33742
t RSTDUR
12
15
18
33742S
t RSTDURS
3.0
3.5
4.0
t WUF
8.0
20
38
s
t DOUT
200
360
520
s
Slew Rate 3
60
100
210
Slew Rate 2
70
110
225
Slew Rate 1
80
130
255
Slew Rate 0
110
200
310
Slew Rate 3
20
65
110
Slew Rate 2
25
80
150
Slew Rate 1
35
100
200
Slew Rate 0
50
160
300
10
50
140
INPUT PINS (L0, L1, L2, AND L3)
Wake-up Filter Time
CAN MODULE – SIGNAL EDGE RISE AND FALL TIMES (CANH, CANL)
Dominant State Timeout
Propagation Loop Delay TXD to RXD (Recessive to Dominant)(36)
Propagation Delay TXD to CAN (Recessive to Dominant)(37)
t LRD
ns
t TRD
Propagation Delay CAN to RXD (Recessive to Dominant)(38)
t RRD
Propagation Loop Delay TXD to RXD (Dominant to Recessive)(36)
t LDR
ns
ns
Slew Rate 3
100
150
200
Slew Rate 2
120
165
220
Slew Rate 1
140
200
250
Slew Rate 0
250
340
410
Slew Rate 3
60
125
150
Slew Rate 2
65
150
190
Slew Rate 1
75
180
250
200
310
460
t RDR
20
30
60
t SL3
t SL2
t SL1
t SL0
4.0
19
40
3.0
13.5
20
2.0
8.0
15
1.0
5.0
10
tBUS
60k
—
1.0M
Propagation Delay TXD to CAN (Dominant to Recessive)(37)
t TDR
Slew Rate 0
Propagation Delay CAN to RXD (Dominant to Recessive)
(38)
ns
Non-Differential Slew Rate (CANL or CANH)
Slew Rate 3
Slew Rate 2
Slew Rate 1
Slew Rate 0
Bus Communication Rate
ns
ns
V/s
bps

36. See Figure 8, page 20.
37. See Figure 9, page 20.
38. See Figure 10, page 21.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
19
ELECTRICAL CHARACTERISTICS
TIMING DIAGRAMS
TIMING DIAGRAMS
t PCLK
CS
t WSCLKH
t LEAD
t LAG
SCLK
t WSCLKL
t SIH
t SISU
MOSI
Undefined
DI 8
Don’t Care
DI 0
t VALID
Don’t Care
t SODIS
t SOEN
MISO
DO 0
DO 8
Note Incoming data at MOSI pin is sampled by the 33742 at SCLK falling edge. Outgoing data at MISO pin
is set by the 33742 at SCLK rising edge (after t VALID delay time).
Figure 7. SPI Timing Diagram
tLRD
TXD
2.0 V
0.8 V
tLDR
2.0 V
RXD
0.8 V
Figure 8. Propagation Loop Delay TXD to RXD
tTRD
TXD
0.8 V
VDIFF
2.0 V
tTDR
0.9 V
0.5 V
VDIFF = VCANH - VCANL
Figure 9. Propagation Delay TXD to CAN
33742
20
Analog Integrated Circuit Device Data
Freescale Semiconductor
ELECTRICAL CHARACTERISTICS
TIMING DIAGRAMS
tRDR
0.9 V
VDIFF
tRRD
0.5 V
2.0 V
RXD
0.8 V
Figure 10. Propagation Delay CAN to RXD
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
21
FUNCTIONAL DESCRIPTION
INTRODUCTION
FUNCTIONAL DESCRIPTION
INTRODUCTION
The 33742 and the 33742S are system basis chips (SBCs) dedicated to automotive applications. Their functions include the
following:
• One fully protected 5.0 V voltage regulator with 200 mA total output current capability available at the VDD pin.
• VDD regulator under-voltage reset function, programmable window or time-out software watchdog function.
• Internal driver (V2) for an external series pass transistor to implement a second 5.0 V voltage regulator.
• Two running modes: Normal and Standby modes set by the system microcontroller.
• Sleep and Stop modes low power operating modes to reduce an application’s current consumption while providing a wakeup capability from the CAN interface, L3 : L0 wake-up inputs, or from a timer wake-up.
• Programmable wake-up input and cyclic sense wake-ups.
• CAN high-speed physical bus interface with TXD and RXD fault diagnostic capability and enhanced protection features.
• An SPI interface for use in communicating with a MCU and Interrupt outputs to report SBC status, perform diagnostics, and
report wake-up events.
FUNCTIONAL PIN DESCRIPTION
RECEIVE AND TRANSMIT DATA (RXD AND TXD)
The RXD and TXD pins (receive data and transmit data pins, respectively) are connected to a microcontroller’s CAN protocol
handler. TXD is an input and controls the CANH and CANL line state (dominant when TXD is LOW, recessive when TXD is
HIGH). RXD is an output and reports the bus state (RXD LOW when CAN bus is dominant, HIGH when CAN bus is recessive).
The RXD terminal is a push-pull structure between the V2 pin and GND.
Voltage Digital Drain (VDD)
The VDD pin is the output pin of the 5.0 V internal regulator. It can deliver up to 200 mA. This output is protected against overcurrent and over-temperature. It includes an over-temperature pre-warning flag, which is set when the internal regulator
temperature exceeds 130 °C typical. When the temperature exceeds the over-temperature shutdown (170 °C typical), the
regulator is turned off.
VDD includes an under-voltage reset circuitry, which sets the RST pin LOW when VDD is below the under-voltage reset
threshold.
RESET OUTPUT (RST)
The RESET pin RST, is an output that is set LOW when the device is in reset mode. The RST pin is set HIGH when the device
is not in reset mode. RST includes an internal pull-up current source. When RST is LOW, the sink current capability is limited,
allowing RST to be shorted to 5.0 V for software debug or software download purposes.
INTERRUPT OUTPUT (INT)
The Interrupt pin INT, is an output that is set LOW when an interrupt occurs. INT is enabled using the Interrupt Register (INTR).
When an interrupt occurs, INT stays LOW until the interrupt source is cleared.
INT output also reports a wake-up event by a 10 s typical pulse when the device is in Stop mode.
VOLTAGE SOURCE 2 (V2)
The V2 pin is the input sense for the V2 regulator. It is connected to the external series pass transistor. V2 is also the 5.0 V
supply of the internal CAN interface. It is possible to connect V2 to an external 5.0 V regulator or to the VDD output when no
external series pass transistor is used. In this case, the V2CTRL pin must be left open. Refer to Figure 31, SBC Typical
Application Schematic, page 57.
VOLTAGE SOURCE 2 CONTROL (V2CTRL)
The V2CTRL pin is the output drive pin for the V2 regulator connected to the external series pass transistor.
33742
22
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DESCRIPTION
FUNCTIONAL PIN DESCRIPTION
VOLTAGE SUPPLY (VSUP)
The VSUP pin is the battery supply input of the device.
HIGH SIDE OUTPUT (HS)
The HS pin is the internal high side driver output. It is internally protected against over-current and over-temperature.
LEVEL 0-3 INPUTS (L0: L3)
The L0 : L3 pins can be connected to contact switches or the output of other ICs for external inputs. The input states can be
read by SPI. These inputs can be used as wake-up events for the SBC when operating in the Sleep or Stop mode.
CAN HIGH AND CAN LOW OUTPUTS (CANH AND CANL)
The CAN High and CAN Low pins are the interfaces to the CAN bus lines. They are controlled by TXD input level, and the
state of CANH and CANL is reported through RXD output. A 60 termination resistor is connected between CANH and CANL
pins.
SERIAL DATA CLOCK (SCLK)
SCLK is the Serial Data Clock input pin of the serial peripheral interface.
MASTER IN SLAVE OUT (MISO)
MISO is the Master In Slave Out pin of the serial peripheral interface. Data is sent from the SBC to the microcontroller through
the MISO pin.
MASTER OUT SLAVE IN (MOSI)
MOSI is the Master Out Slave In pin of the serial peripheral interface. Control data from a microcontroller is received through
this pin.
CHIP SELECT (CS)
CS is the Chip Select pin of the serial peripheral interface. When this pin is LOW, the SPI port of the device is selected.
WATCHDOG OUTPUT (WDOG)
The Watchdog output pin is asserted LOW to flag that the software watchdog has not been properly triggered.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
23
FUNCTIONAL DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
MC33742 - Functional Block Diagram
Integrated Supply
Outputs
VSUP Control & Monitor
5.0V Linear
Regulator (LDO)
Analog Circuitry
Oscillator
5.0V Regulator
Base PNP Drive
Mode Control
Programmable Wake-up
High-side
Switch
MCU Interface
SPI Interface
CAN Interface / Control
Integrated Supply
Analog Circuitry
Reset & INT
Watchdog Timer
CAN Physical Layer
Interface
MCU Interface
Outputs
OUTPUTS
5.0 V LINEAR REGULATOR (LDO)
This low dropout linear regulator (V1) outputs a regulated 5.0 V at 200 mA. The associated monitoring circuit provides
detection of under-voltage, over-current, and short-circuit conditions, as well as over-temperature and a reset function.
5.0 V REGULATOR BASE PNP DRIVE
The V2 linear regulator control circuitry provides drive for an external series pass transistor (PNP type). The 5.0 V output tracks
the V1 regulator
HIGH SIDE SWITCH
The high switch provides a 2.0 ohm (typ.) RDSON MOSFET driver connected to the VSUP pin. The output is protected against
short-circuit conditions and provides over-temperature shutdown.
CAN PHYSICAL LAYER INTERFACE
This circuitry provides communication between the TXD & RXD pins, from/to the MCU, and the CANL & CANH pins of the
CAN physical interface. The various modes of the CAN interface are controlled through the SPI control registers.
INTEGRATED SUPPLY
VSUP CONTROL & MONITOR
This circuitry protects the IC from transient conditions such as vehicle jump-start (27 V) and load dump (40 V). If the VSUP
voltage falls below 3.0 V (or a 6.0 V warning interrupt), an under-voltage detection is reported.
33742
24
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DESCRIPTION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
ANALOG CIRCUITRY
OSCILLATOR
This circuit is used to generate the internal timings for reset, watchdog, cyclic wake-up, filtering time, etc.
MODE CONTROL
The 4 operating modes of the IC are controlled through the SPI control registers. There are also several special modes
possible.
PROGRAMMABLE WAKE-UP
The 4 inputs are used in conjunction with various SPI control register bits to determine the wake-up conditions and the reaction
of the IC. They can be connected to contact switches or other ICs.
MCU INTERFACE
SPI INTERFACE
The IC and the MCU communicate using the SPI control and status reporting registers. The clock speed (SCLK) can be as
high as 4.0 MHz.
RESET & INT
These 2 outputs notify the MCU when the IC is in reset mode, or when an enabled interrupt condition has occurred.
WATCHDOG TIMER
The timer can be used as a watchdog window or watchdog timeout function. The SPI control register provide the choice as
well as the timeout value. When the watchdog timer is not properly serviced by the MCU, an error signal (WDOGN low) and a
reset signal (RSTN low) are output.
CAN INTERFACE/CONTROL
The operation of the CAN interface is controlled by the MCU through the use of SPI control register bits.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
25
FUNCTIONAL DEVICE OPERATION
FUNCTIONAL INTERNAL BLOCK DESCRIPTION
FUNCTIONAL DEVICE OPERATION
SUPPLY VOLTAGE AT VSUP
The 33742 receives its operating voltage via the VSUP pin. An external diode is needed in series with the VSUP pin and the
supply voltage to protect the SBC against negative transients or from a reverse battery situation that can occur in a vehicle
application. The 33742 will operate from a supply voltage input as low as 4.5 VDC to as high as 27 VDC. The later voltage is
often encountered during a vehicle jump-start.
The VSUP pin can tolerate automotive transient conditions such as load dump to 40 V. The SBC is able to detect when VSUP
falls below 3.0 V typical. This under-voltage state is detected and retained in the parts Mode Control Register (MCR) as the
BATFAIL bit. This detection capability is available across all operating modes.
Note For a detailed description of all the registers mentioned in this section, refer to the section titled SPI Interface And
Register Description beginning on page 46.
The SBC incorporates a VSUP level early warning function, which provides a maskable interrupt if the VSUP voltage level falls
below 6.0 V typical. Hysteresis is used to reduce false detections. The early warning function works only in Normal and Standby
operation modes. An under-voltage at the VSUP pin is reported in the Input / Output Register (IOR).
VDD REGULATOR
The VDD regulator provides a 5.0 V low dropout voltage capable of supplying up to 200 mA with monitoring circuitry for undervoltage detection and a reset function. The VDD regulator is protected against over-current and short-circuit conditions. It has
over-temperature detection and will set warning flags (bit VDDTEMP in the MCR and INTR registers) and has over-temperature
shutdown with hysteresis.
V2 REGULATOR
The V2 regulator feature provides for a second 5.0 VDC voltage source The internal V2 circuitry will drive an external series
pass transistor, substantially increasing the available supply current. Two pins, the V2 and the V2CTRL, are used to sense and
drive the series pass transistor. The output voltage is 5.0 V and tracks the VDD regulator. The MJD32C transistor is
recommended for use as the external pass device. Other PNP transistors can be used but depending on the device’s gain, an
external resistor-capacitor network might be needed. V2 is also the supply voltage for the on-board CAN module. An undervoltage condition for the V2 voltage is reported in the IOR Register (bit V2LOW set to logic [1] if V2 falls below 4.0 V typical).
HS VSUP SWITCH OUTPUT
The HS output is a 2.0  typical switch tied to the VSUP pin. It can power or bias external switches and their associated pullup or put-downs or other circuitry. An example is biasing a set of switches connected to the L0 : L3 wake-up input pins. The HS
VSUP output current is limited to 200 mA and is protected against short-circuits conditions and will report an over-temperature
shutdown condition (bit HSOT in the IOR register and bit HSOT - V2LOW in the INTR register).
The HS output “on” state is set by the HSON bit in the IOR register. A cyclic mode of operation can be implemented using an
internal timer in the Sleep and Stop operating modes. It can also be turned on in Normal or Standby modes to drive loads or
supply peripheral components. No internal protection circuitry is provided, however. Dedicated chip protection circuitry is required
for inductive load applications. The HS output pin should not go below - 0.3 V.
BATTERY FAIL EARLY WARNING
Refer to the previous discussion under the heading, Supply Voltage at VSUP.
INTERNAL CLOCK
The 33742 has an internal clock used to generate all timings (reset, watchdog, cyclic wake-up, filtering time, etc.). There are
two on-board oscillators: a higher accuracy (±12 percent) oscillator used in Normal Request, Normal, and Standby modes, and
a lower accuracy (±30 percent) oscillator used during Sleep and Stop modes.
33742
26
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
OPERATIONAL MODES
INTRODUCTION
The 33742 has four modes of operation, all controllable via the SPI. The modes are Standby, Normal, Stop, and Sleep. An
additional temporary mode called Normal Request mode is automatically accessed by the device after reset or wake-up from
Stop mode. A Reset mode is also implemented. Special modes and configurations are possible for debug and program
microcontroller flash memory.
Table , page 28, offers a summary of the functional modes.
STANDBY MODE
In Standby mode only the VDD regulator is ON. The V2 regulator is turned OFF by disabling the V2CTRL pin. Other functions
available are the L0 : L3 inputs read through via the SPI and HS output activation.
The CAN interface is not able to send messages. If a CAN message is received, the CANWU bit is set. The watchdog timer
is running.
NORMAL MODE
In Normal mode, both the VDD and V2 regulators are in the ON state. All functions are available in this operating mode
(watchdog, wake-up input reading through SPI, HS activation, and CAN communication). The watchdog timer is running and
must be periodically cleared through SPI.
STOP MODE
The V2 regulator is turned OFF by disabling the V2CTRL pin. The VDD regulator is activated in a special low power mode
supplying only a few mA of current. This maintains “keep alive” power for the application’s MCU while the MCU is in a powersaving state (i.e., a MCU’s version of Stop or Wait). In the Stop mode, the supply current available from VSUP pin is very low.
Both parts (the SBC or the MCU) can be awakened from either the 33742 side (for example, cyclic sense, forced wake-up,
CAN message, wake-up inputs, and over-current on VDD) or from the MCU side (key wake-up, etc.).
Stop mode is always selected via SPI. In Stop mode, the watchdog software may be either running or not running depending
upon selection by SPI (Reset Control Register [RCR], bit WDSTOP). To clear a running watchdog timer, the SBC must be
awakened using the CS pin (SPI wake-up). In Stop mode, wake-up is identical to that in Sleep mode, with the addition of CS and
VDD over-current wake-up. Refer to Table , page 28.
SLEEP MODE
In Sleep mode, the VDD and V2 regulators are OFF. Current consumption from the VSUP pin is cut. In Sleep mode, the SBC
can be awakened by sensing individual level individual level changes in the L0 : L3 inputs, by cyclic checking of the L0 : L3 inputs,
by the forced wake-up timer, or from the CAN physical interface upon receiving a CAN message. When a wake-up occurs, the
SBC goes first into the Reset mode before entering Normal Request mode.
RESET MODE
In the Reset mode, the RST pin is LOW and a timer runs for t RSTDUR time. After t RSTDUR has elapsed, the 33742 enters the
Normal Request operating mode. The Reset mode is entered if a reset condition occurs (VDD LOW, watchdog time-out, or
watchdog trigger in a closed window).
NORMAL REQUEST MODE
The Normal Request mode is a temporary operating mode automatically entered by the SBC after the Reset mode or after the
33742 wakes up from the Stop mode.
After a wake-up from the Sleep mode or after a device power-up, the SBC enters the Reset mode prior to entering the Normal
Request mode. After a wake-up from the Stop mode, the 33742 enters the Normal Request mode directly.
In Normal Request mode, the VDD regulator is ON, the V2 regulator is OFF, and the RST pin is HIGH. As soon as the SBC
enters the Normal Request mode, an internal 350ms timer is started (parameter tNRTOUT). During this time, the application’s MCU
must address the 33742 via SPI and configure the TIM1 sub register to select the watchdog period. This is required of the SBC
to stop the 350 ms watchdog timer and enter the Normal or Standby mode and to set the watchdog timer configuration.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
27
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
NORMAL REQUEST ENTERED AND NO WATCHDOG CONFIGURATION OCCURS
If the Normal Request mode is entered after the SBC powers up or after a wake-up from Stop mode and no watchdog
configuration occurs before the 350 ms time period has expired, the device enters the Reset mode. If no watchdog configuration
is performed, the 33742 will cycle from the Normal Request mode to Reset mode to Normal Request mode.
If the Normal Request mode is entered after a wake-up from Sleep mode, and no watchdog configuration occurs while the
33742S is in Normal Request mode, the SBC returns to the Sleep mode.
Table 7. Table of Operations
Mode
Voltage Regulator
HS Switch
Wake-up
Capabilities
(if Enabled)
RST Pin
INT Pin
Watchdog
Software
CAN Cell
–
–
–
Running
TXD / RXD
Running
Low power
Normal
Request
VDD: ON,
V2: OFF,
HS: OFF
–
Low for t RSTDUR time,
then HIGH
Normal
VDD: ON,
V2: ON,
HS: Controllable
–
Normally HIGH.
If enabled, signal
Active LOW if WDOG
failure (VDD
Pre-warning
or VDD under-voltage
Temp, CAN, HS)
occurs
Standby
VDD: ON,
V2: OFF,
HS: Controllable
–
Same as Normal
mode
Same as Normal
mode
Stop
VDD: ON
(Limited Current
Capability),
V2: OFF,
HS:OFF or Cyclic Sense
CAN, SPI, L0 : L3,
Cyclic Sense,
Forced Wake-up,
IDD Over-current(40)
Normally HIGH.
Active LOW if
WDOG(41)
or VDD under-voltage
occurs
Signal 33742S
wake-up and
IDD > IDDS-WU
(not maskable)
Sleep
VDD: OFF,
V2: OFF,
HS: OFF or Cyclic
CAN, SPI,
L0 : L3, Cyclic Sense
Forced Wake-up
LOW
Not Active
Normal
Debug(39)
Same as Normal
–
Standby
Debug(39)
Same as Standby
–
Stop
Debug(39)
Same as Stop
Flash
Programming
Forced externally
Running if
Low power.
enabled.
Wake-up capability
Not running if
if enabled
disabled
Not running
Low power.
Wake-up capability
if enabled
Normally HIGH.
Same as Normal
Active LOW if VDD
under-voltage occurs
Not running
Same as Normal
Normally HIGH.
Same as Standby
Active LOW if VDD
under-voltage occurs
Not running
Same as Standby
Same as Stop
Normally HIGH.
Active LOW if VDD
under-voltage occurs
Same as Stop
Not running
Same as Stop
–
Not operating
Not operating
Not operating
Not operating
Notes
39. Mode entered via special sequence described under the heading Debug Mode: Hardware and Software Debug with the 33742,
beginning on page 34.
40. IDD over-current always enabled.
41.
WDOG if enabled.
APPLICATION WAKE-UP FROM THE 33742
When the application is in Stop mode, it can be awakened from the SBC side. When a wake-up condition is detected by the
SBC (for example, CAN, wake-up input), the 33742 enters the Normal Request mode and generates an interrupt pulse at the
INT pin.
33742
28
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
APPLICATION WAKE-UP FROM THE MCU
When the device is in the Stop mode, a wake-up event may come from the system MCU. In this case the MCU selects the
device the using a LOW-to-HIGH transition on the 33742 CS pin. Then the 33742S goes into Normal Request mode and
generates an interrupt pulse at the INT pin.
STOP MODE CURRENT MONITOR
If the VDD output current exceeds an internal set threshold (IDDS-WU), the SBC automatically enters the Normal Request mode
and generates an interrupt at the INT pin. The interrupt is a non-maskable and the INTR register will have no flag set.
INTERRUPT GENERATION WHEN WAKE-UP FROM STOP MODE
When the SBC wakes from Stop mode, it first enters the Normal Request mode before generating a 10 s typical pulse on the
INT pin. These are non-maskable interrupts with the wake-up event read through the SPI registers, the CANWU bit in the CAN
Register (CANR), or the LCTRx bit in the Wake-up Register (WUR). In case of wake-up from Stop mode over-current situation
or from forced wake-up, no bits are set. After the INT pulse, the 33742 accepts SPI command after a time delay (t S-1STSPI).
WATCHDOG SOFTWARE IN STOP MODE
If the SBC watchdog is enabled, the application must provide a “system ok” response before the end of the 33742 watchdog
time. Typically an MCU initiates the wake-up of the 33742 through the SPI wake-up (CS activation). The SBC will awaken and
jump into the Normal Request mode. The MCU has to configure the 33742 to go to either Normal or Standby mode. The MCU
can then decide to return to the Stop mode.
If no MCU wake-up occurs within the watchdog time period, the SBC activates the RST pin and jumps into the Normal Request
mode. The MCU can then be re-initialized.
STOP MODE ENTER COMMAND
Stop mode is entered at the end of the SPI message at the rising edge of the CS. (Refer to the t CS-STOP data in the Dynamic
Electrical Characteristics table on page 16.) Once Stop mode is entered, the SBC can wake up from a VDD regulator over-current
detection state. In order to allow time for the MCU to complete the last CPU instruction and enter its low power mode, a deglitcher
time of 40 s typical is implemented.
Figure 11, page 29, depicts the operation of entering the Stop mode.
SPI Stop/Sleep
Command
SPI CS
t CS-STOP
33742 in Normal
or Standby mode
t IDD-DGLT
33742 in Stop mode.
No IDD over IDD-DGLT
33742 in Stop mode.
IDD over IDD-DGLT
Figure 11. Entering the Stop Mode
WATCHDOG SOFTWARE (RST AND WDOG) (SELECTABLE WATCHDOG WINDOW 
OR WATCHDOG TIME-OUT)
A watchdog is used in the SBC Normal and Standby modes for monitoring the MCU operation. The watchdog timer may be
implemented as either a watchdog window or watchdog timeout, selectable by SPI (TIM1 sub register, bit WDW). Default
operation is a watchdog window.
The watchdog period can be set from 10 to 350 ms (TIM1 sub register, bits WDT0 and WDT1). When a watchdog window is
selected, the closed window is the first part of the selected period, and the open window is the second part of the period. (Refer
to Timing Register (TIM1 / 2) beginning on page 52.)
The watchdog can only be cleared within the open window time period. Any attempt to clear watchdog in the closed window
will generate a reset. The watchdog is cleared addressing the TIM1 sub register using the SPI.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
29
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
RST PIN DESCRIPTION
A 33742 output is available to perform a reset of the MCU. Reset can happen from:
• VDD Falling Out of Range — If VDD falls below the reset threshold (V RSTTH), the RST pin is pulled LOW until VDD returns to
the normal voltage.
• Power-ON Reset — At 33742 power-on or wake-up from Sleep mode, the RST pin is maintained LOW until VDD is within its
operation range.
• Watchdog Timeout — If watchdog is not cleared, the 33742 will pull the RST pin LOW for the duration of the reset time
(t RSTDUR).
RST AND WDOG OPERATION
Table 8 describes watchdog and reset output modes of operation. RST is activated in the event VDD fall or watchdog is not
triggered. WDOG output is active LOW as soon as RST goes LOW and stays LOW as long as the watchdog is not properly reset
via SPI. The WDOG output pin is designed as a push-pull structure that can drive off chip components signaling, for instance,
errant MCU operation.
Figure 12 illustrates the device behavior in the event the TIM1 register in not properly accessed. In this case, a software reset
occurs and the WDOG pin is set LOW until the TIM1 register is properly accessed.
Table 8. Watchdog and Reset Output Operation
Events
WDOG
Output
RST Output
Device Power up
LOW to HIGH
LOW to HIGH
VDD Normal, WDOG Properly Triggered
HIGH
HIGH
VDD < VRSTTH
HIGH
LOW
WDOG Timeout Reached
LOW (42)
LOW
Notes
42. WDOG stays LOW until the TIM1 register is properly addressed through SPI.
33742
30
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
Device power up
Device is in Normal mode, W/D refresh failure
VSUP
VDD
VDD
RST
RST
WDOG
WDOG
SPI
Watchdog
Period
SPI
Mode
RESET
N-Request
Normal
SPI CS
Power up
Watchdog refresh failure
Device is in stop mode
Device is in sleep mode
VSUP
VSUP
VDD
VDD
RST
INT
WDOG
WDOG
SPI
SPI
Mode
Sleep
RESET
N-Request
Wake-up event
Normal
Mode Stop
N-Request
Normal
Wake-up event
Legend: TIM1 register write
Figure 12. RST and WDOG Output Operation
WAKE-UP CAPABILITIES
Several wake-up capabilities are available to the SBC when it is in Sleep or Stop mode. When a wake-up has occurred, the
wake-up event is stored in the Wake-up Register (WUR) or the CAN register and read by the MCU to determine the wake-up
source. The wake-up options are selectable through SPI while the 33742 is in Normal or Standby mode and prior to entering low
power modes (Sleep or Stop mode). When a wake-up occurs in Sleep mode, the SBC reactivates the VDD supply. It generates
an interrupt if a wake-up occurs from Stop mode.
WAKE-UP FROM WAKE-UP INPUTS (L0 : L3) WITHOUT CYCLIC SENSE
The wake-up lines are used to determine the state of external switches and if changes occurred to wake up the MCU (in Sleep
or Stop modes). The wake-up pins L0 : L3 are able to handle up to 40 VDC. The internalize” threshold is 3.0 V typical, and these
inputs can be used as an input port expander. The wake-up input states are read through SPI (WUR register).
In order to select and activate direct wake-up from the L0 : L3 inputs, the WUR register must be configured with the appropriate
level sensitivity. Additionally, the Low Power Control (LPC) Register must be configured with 0xx0 data (bits LX2HS and
HSAUTO are set to 0).
The sensitivity of the L0 : L3 inputs is selected by the WUR register. Level sensitivity is configured by L0 : L3 input pairs: L0 and
L1 level sensitivity are configured together, while L2 and L3 are configured together.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
31
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
CYCLIC SENSE WAKE-UP (CYCLIC SENSE TIMER AND WAKE-UP INPUTS L0 : L3)
The 33742 can wake up upon state change of one of the four wake-up input lines (L0 : L3). The external pull-up or pull-down
resistor of the switches associated with the wake-up input lines can be biased from the HS VSUP switch. The HS switch is
activated in Sleep or Stop modes from an internal timer. Cyclic Sense and Forced Wake-up are exclusive states. If Cyclic Sense
is enabled, Forced Wake-up cannot be enabled.
In order to select and activate the cyclic sense wake-up from the L0 : L3 inputs, the WUR register must be configured with the
appropriate level sensitivity and the LPC register must be configured with 1xx1 data (bit LX2HS set at 1 and bit HSAUTO set 
at 1. The wake-up mode selection (direct or cyclic sense) is valid for all four wake-up inputs.
FORCED WAKE-UP
The SBC can wake-up automatically after a predetermined time spent in Sleep or Stop mode. Cyclic Sense and Forced Wakeup are exclusive. If Forced Wake-up is enabled (FWU bit set to 1 in the LPC register), Cyclic Sense cannot be enabled.
CAN INTERFACE WAKE-UP
The SBC incorporates a high-speed 1.0 Mbps CAN physical interface. It is compatible with ISO 11898-2 standard. The
operation of the CAN physical interface is controlled through the SPI. The CAN operating modes are independent of the 33742
operational modes.
The SBC can wake up from a CAN message if the CAN wake-up feature is enabled. Refer to the section titled Logic
Commands And Registers beginning on page 46 for details of the wake-up detection.
SPI WAKE-UP
The 33742 can be awakened by changes on the CS pin in Sleep or Stop modes. Wake-up is detected as a LOW-to-HIGH level
transition on the CS pin. In the Stop mode, this corresponds to a condition where an MCU and the SBC are both in the Stop mode
and when the application wake-up event comes through the MCU.
33742 POWER-UP AND WAKE-UP FROM SLEEP MODE
After device or system power-up, or after the SBC awakens from Sleep mode, the 33742S enters into the Reset mode prior
to moving into Normal Request mode.
Figure 13, shows the device state diagram. Figure 14, shows device operation after power-up.
33742
32
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
Watchdog: Timeout OR VDD Low
Watchdog: Timeout & Nostop &!BATFAIL
V

DD
Power
Down
Lo
w
2
(4
4)
1
Stop
SPI: Stop & CS
LOW to HIGH
Transition
Watchdog: Timeout OR VDD Low
Nostop and SPI: Sleep
& CS LOW to HIGH
Transition
R
Normal
1
Nostop and SPI:
Sleep & CS LOW
to HIGH
ut
O
SPI: Normal
:T
im
eo
4
Standby
3
SP
do
g
VDD Low OR Watchdog:
Timeout 350 ms & Nostop
Wake-up
ch
Normal Request
g:
do
ch r
at e
W rigg
T
33742S Power-
1
1
I:
H Sto
ig p
h &
Tr C
an S
s i Lo
tio w
n to
Reset
W
at
SPI: Standby and
Watchdog Trigger
2
SPI: Standby
Reset Counter (3.4 ms)
Expired
Wake-Up
(VDD High Temperature OR [VDD Low > 100 ms & VSUP > BFew]) & Nostop &!BATFAIL
1
2
3
4
Sleep
Denotes priority
State Machine Description
Nostop = Nostop bit = 1
! Nostop = Nostop bit = 0
BATFAIL = Batfail bit = 1
! BATFAIL = Batfail bit = 0
VDD Over-temperature = VDD thermal shutdown occurs
VDD LOW = VDD below reset threshold
VDD LOW > 100 ms = VDD below reset threshold for more than 100 ms
Watchdog: Trigger = TIM1 subregister write operation
VSUP > BFew = VSUP > Battery Fail Early Warning (6.1 V typical)
Watchdog: Timeout = TIM1 register not written before watchdog timeout period
expired, or watchdog written in incorrect time window if watchdog window
selected (except Stop mode). In Normal Request mode, timeout is 355 ms
p2.2 (350 ms p3) ms.
SPI: Sleep = SPI write command to MCR register, data sleep
SPI: Stop = SPI write command to MCR register, data stop
SPI: Normal = SPI write command to MCR register, data normal
SPI: Standby = SPI write command to MCR register, data standby
Notes
43. These two SPI commands must be sent consecutively in this sequence.
44. If watchdog activated.
Figure 13. SBC State Diagram (Not Valid in Debug Modes)
Power-up
Operation after power-up if no trigger appears
Operation after reset of BATFAIL if no trigger appears
Reset
Normal
Request
Yes
No
Trigger
No
No
Batfail
No Stop
Yes
Sleep
Yes
Normal
Figure 14. Operation After SBC Power-up
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
33
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
DEBUG MODE: HARDWARE AND SOFTWARE DEBUG WITH THE 33742
When a SBC, and the MCU it serves, is used on the same printed circuit board, both the MCU software and the 33742
operation must be debugged concurrently. The following features permit system debugging by allowing the disabling of the SBC
internal software watchdog timer.
DEVICE POWER-UP, RESET PIN CONNECTED TO VDD
The VDD voltage is available when the 33742 power-up but the 33742 will not have received any SPI communication to
configure itself. Until set up by the system MCU, the 33742 will generate a reset every 350 ms until the part is configured. To
avoid continuous MCU hardware resets, the 33742’s RST pin can be connected directly to the VDD pin by a hardware jumper.
DEBUG MODES WITH SOFTWARE WATCHDOG DISABLED THOUGH SPI (NORMAL DEBUG, STANDBY
DEBUG, AND STOP DEBUG)
The software configurable watchdog can be disabled through the SPI. To set the watchdog disable while limiting the risk of
inadvertently disabling the watchdog timer during normal 33742 operation, it is recommended that the disable be done using the
following sequence:
•
•
•
•
•
Step 1– Power down the SBC.
Step 2 – Power up the SBC. This sets the BATFAIL bit, allowing the 33742 to enter Normal Request mode.
Step 3 – Write to the TIM1 sub register to allow the SBC to enter Normal mode.
Step 4 – Write to the MCR register with data 0000. This enables the debug mode. Complete SPI byte is 0001 0000.
Step 5 – Write to the MCR register normal debug. SPI byte is 0001 x101.
Important While in debug mode, the SBC can be used without having to clear the watchdog on a regular basis to facilitate
software and hardware debug.
• Step 6 – To leave the debug mode, write 0000 to the MCR register.
At Step 2, the SBC is in Normal Request. Steps 3, 4, and 5 should be completed consecutively and within the 350 ms time
period of the Normal Request mode. If not, the 33742 will go into Reset mode and enter Normal Request again.
Figure 15, page 34, illustrates debug mode selection.
VSUP
VDD
BATFAIL
TIM1(Step 3)
MCR (Step 5)
MCR (Step 6)
SPI
MCR (Step 4)
Debug Mode
SPI: Read BATFAIL
33742 in Debug mode.
No Watchdog
33742 not in Debug mode.
Watchdog ON
Figure 15. Entering Debug Mode
When the SBC is operating in the debug mode and has been set into Stop Debug or Sleep mode, a wake-up causes the 33742
to enter the Normal Request mode for 350 ms. To avoid having the SBC generate an unwanted reset (enter Reset mode), the
next debug mode (Normal Debug or Standby Debug) should be configured within the 350 ms time window of the Normal Request
mode.
To avoid entering debug mode after a power-up, first read the BATFAIL bit (MCR read) and write 0000 into the MCR register.
Figures 16 and 17, page 35, show the detailed operation of the SBC once the debug mode has been selected.
33742
34
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
Watchdog: Timeout 350 ms
Reset Counter
(3.4 ms) Expired
Power
Down
Reset
Watchdog: 
Trigger
Normal Request
SPI: MCR (0000) and Normal Debug
Normal
Normal Debug
SPI: MCR (0000) and Standby Debug
Standby Debug
Figure 16. Transitions to Enter Debug Modes
Watchdog: Timeout 350 ms
og
: Tr
ig g
er
R
D
Normal
by
ma
l
De
b
E
St
an
d
or
I:
I: N
ug
SP
SPI: Standby Debug
Standby Debug
eb
ug
Standby
R
Sleep
&!BATFAIL & NOSTOP
& SPI: Sleep
hd
R
SP
SPI: Stop Debug & CS Low to
High Transition
SPI: Stop
Stop Debug
Wa
tc
R
Wake-up
Reset
E
SPI: Standby Debug
Normal Debug
SPI: Normal Debug
R
SPI: Normal Debug
W
ak
eup
R
R
Reset Counter
(3.4 ms) Expired
Normal Request
SPI: Standby &
Watchdog: Trigger
Wake-up
Stop (1)
R
(1) If Stop mode is entered, it is entered without watchdog, no matter the WDSTOP bit.
(E) Debug mode entry point (Step 5 of the Debug mode entering sequence).
(R) Represents transitions to Reset mode due to V1 low.
Figure 17. Simplified 33742S State Diagram in Debug Modes
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
35
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
MCU FLASH PROGRAMMING CONFIGURATION
To allow for new software to be loaded into a SBC’s MCU NVM or to standalone EEPROM or Flash, the 33742 is capable of
having (1) VSUP applied to it to from an external power 5.0 V supply and (2) having the RST and the WDOG outputs pins
eternally forced to 0.0 or 5.0 V without damaging the device.
This allows the SBC to be externally powered and off-board signals to be applied to the reset pins. No functions of the 33742
are operating. Figure 18 illustrates a typical configuration for the connection of programming and debugging tools.
The VSUP should be left open or forced to a value equal to or above V.
The VDD regulator uses an internal pass transistor between VSUP and the VDD output pin. Biasing the VDD output pin with
a voltage greater than VDD potential will force current through the body diode of the internal pass transistor to the VSUP pin.
The RST pin is periodically pulled LOW for the t RSTDUR time (device in Reset mode), before being pulled to VDD for 350 ms
typical (device in Normal Request mode). During the time reset is LOW, the RST pin sinks 5.0 mA maximum (IPDW).
VDD
VSUP (Open or > 5.0 V
RST
33742
WDOG
5.0 V
MCU with
Flash Memory
Programming Bus
Programming Tool
Note External supply and sources applied to VDD, RST, and WDOG test points on application circuit board.
Figure 18. Simplified Schematic for Microcontroller Flash Programming
33742
36
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
CAN PHYSICAL INTERFACE
The SBC features a high-speed CAN physical interface for bus communication from 60 kbps up to 1.0 Mbps. Figure 19 is a
simplified block diagram of the CAN interface of the 33742.
33742
V2
V2
V2
SPI Control
TXD
Driver
QH
CANH
V2
CANH Line
Differential
Receiver
RXD
Bus Termination (60 )
2.5 V
CANL Line
V2
CANL
Driver
QL
SPI Control
VSUP
Internal
Wake-up
Signal
Wake-up
Pattern
Recognition
Wake-up
Receiver
SPI Control
Figure 19. Simplified Block Diagram of CAN Interface
CAN INTERFACE SUPPLY
The supply voltage for the CAN transceiver is the V2 pin. The CAN interface also has a supply path from the external supply
line through the VSUP pin. This path is used in CAN Sleep mode to allow wake-up detection.
During CAN communication (transmission and reception), the CAN interface current is sourced from the V2 pin. During CAN
low power mode, the current is sourced from the VSUP pin.
MAIN OPERATION MODES DESCRIPTION
The CAN interface of the SBC has two main operating modes: TXRX and Sleep mode. The modes are controlled by the CAN
SPI Register. In the TXRX mode, which is used for communication, four different slew rates are available for the user. In the
Sleep mode, the user has the option of enabling or disabling the remote CAN wake-up capability.
CAN DRIVER OPERATION IN TXRX MODE
When the CAN interface is in TXRX mode, the driver has two states: recessive or dominant. The driver state is controlled by
the TXD pin. The bus state is reported through the RXD pin.
When TXD is HIGH, the driver is set in recessive state, and CANH and CANL lines are biased to the voltage set at V2 divided
by 2, or approximately 2.5 V.
When TXD is LOW, the bus is set into dominant state: CANL and CANH drivers are active. CANL is pulled to ground, and
CANH is pulled HIGH toward 5.0 V (voltage at V2).
The RXD pin reports the bus state: CANH minus CANL voltage is compared versus an internal threshold (a few hundred
millivolts). If CANH minus CANL is below the threshold, the bus is recessive and RXD is set HIGH. If CANH minus CANL is above
the threshold, the bus is dominant and RXD is set LOW. This is illustrated in Figure 19.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
37
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
TXD
CANH
CANL
Typ 2.5 V
VCANH -VCANL > 900 mV
Typ 2.5 V
VCANH -VCANL < 500 mV
RXD
CAN Recessive State
CAN Dominant State
CAN Recessive State
Figure 20. CAN Interface Levels
TXD AND RXD PINS
The TXD pin has an internal pull-up to V2. The state of TXD depends on the V2 status. RXD is a push-pull structure, supplied
by V2. When V2 is set at 5.0 V and CAN is TXRX mode, RXD reports bus status. For details, refer to Table , page 28, Table 9,
below, and Table 10, page 39.
The TXD pin is a push-pull structure between the V2 pin and GND. The circuitry has a parasitic diode between RXD and V2.
It is illustrated in Figure 25. This parasitic diode is reversed biased in normal operation (TXD voltage is lower or equal to V2). In
case the TXD voltage is greater than V2, a current will flow into the diode.
If the V2 pin is low (e.g. in sleep mode, or in stop with a ballast transistor), the current leakage at V2 is low enough (10 A
max) to ensure than the RXD pin can be pulled up by an external resistor (i.e. the MCU RXD pin internal pull-up).
The states of the RXD pin in the following Table 9 and 10 is dependant upon external circuitry connected to the V2 and RXD
pins.
CAN TXRX MODE AND SLEW RATE SELECTION
The slew rate selection is done via CAN register (refer to Tables 22 through 24 on page 50). Four slew rates are available and
control the recessive-to-dominant and dominant-to-recessive transitions. The delay time from TXD pin to CAN bus, from CAN
bus to RXD, and from the TXD to RXD loop time is affected by the slew rate selection.
Table 9. CAN Interface / 33742S Modes and Pin Status—Operation with Ballast on V2(45)
Mode
CAN Mode
(Controlled by SPI)
V2 Voltage
TXD Pin
RXD Pin(46)
CANH/CANL
(Disconnected from
Other Node)
CAN
Communication
Unpowered
–
0.0 V
LOW
LOW
Floating to GND
NO
Reset (with Ballast)
–
0.0 V
LOW
LOW
Floating to GND
NO
Normal Request
(with Ballast)
–
0.0 V
LOW
LOW
Floating to GND
NO
Normal
Sleep
5.0 V
0.0 V
5.0 V
Floating to GND
NO
Normal
Normal
Slew Rate 0, 1, 2, 3
5.0 V
Internal Pull-up
to V2
Report Bus State
Bus Recessive
HIGH if Bus
CANH = CANL = 2.5 V
Recessive,
LOW if dominant
YES
33742
38
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
Table 9. CAN Interface / 33742S Modes and Pin Status—Operation with Ballast on V2(45)
Standby with
External Ballast
Normal or Sleep
0.0 V
LOW
LOW
Floating to GND
NO
Sleep
Sleep
0.0 V
LOW
LOW
Floating to GND
NO.
Wake-up if enabled
Stop
Sleep
0.0 V
LOW
LOW
Floating to GND
NO.
Wake-up if enabled
Notes
45. See also Figure 31, page 57.
46. The state of the RXD pin is dependant upon: 1) the V2 voltage, 2) the external circuitry connected to RXD, (i.e. the MCU RXD pin), and
3) any external pull-up between RXD and the 5.0 V supply.
Table 10. CAN Interface / 33742 Modes and Pin Status — Operation without Ballast on V2 (47)
Mode
CAN Mode
(Controlled by SPI)
V2 Voltage
TXD Pin
RXD Pin(48)
CANH/CANL
(Disconnected from
Other Node)
CAN
Communication
Unpowered
–
0.0 V
LOW
LOW
Floating to GND
NO
Reset (without Ballast)
–
5.0 V
LOW
LOW
Floating to GND
NO
Normal Request without
Ballast.
V2 Connected to VDD
–
5.0 V
LOW
5.0 V
Floating to GND
NO
Standby without External
Ballast,.
V2 connected to VDD
Normal or Sleep
5.0 V
0.0 V
5.0 V
Floating to GND
NO
Normal without External
Ballast.
V2 Connected to VDD
Normal
Slew Rate 0, 1, 2,3
5.0 V
5.0 V
5.0 V
Bus Recessive
CANH = CANL = 2.5 V
YES
Normal without External
Ballast,.
V2 Connected to VDD
Sleep
5.0 V
0.0 V
5.0 V
Floating to GND
NO
Sleep
Sleep
0.0 V
LOW
LOW
Floating to GND
NO.
Wake-up if enabled
Stop
Sleep
5.0 V
LOW
LOW
Floating to GND
NO.
Wake-up if enabled
Notes
47. See also Figure 36, page 60.
48. The state of the RXD pin is dependant upon: 1) the V2 voltage, 2) the external circuitry connected to RXD, (i.e. the MCU RXD pin), and
3) any external pull-up between RXD and the 5.0 V supply.
CAN SLEEP MODE
The 33742 offers two CAN Sleep modes:
• Sleep mode with CAN wake-up enable: detection of incoming CAN message and SBC wake-up.
• Sleep mode with CAN wake-up disable: no detection of incoming CAN message.
The CAN Sleep modes are set via the CAN SPI register.
In CAN Sleep mode (with wake-up enable or disable), the CAN interface is internally supplied from the VSUP pin. The voltage
at V2 pin can be either 5.0 V or turned off. When the CAN is in Sleep mode, the current sourced from V2 is extremely low. In
most cases the V2 voltage is off; however, the CAN can be placed into Sleep mode even with 5.0 V applied on V2.
In CAN Sleep mode, the CANH and CANL drivers are disabled, and the receiver is also disabled. CANH and CANL are highimpedance mode to ground.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
39
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
CAN SIGNALS IN TXRX AND SLEEP MODES
When the CAN interface is set back into TXRX mode by an SPI command, CAN H and CANL are set in recessive level. This
is illustrated in Figure 21.
TXD
CANH Dominant
CANH
CANL/CANH Recessive
2.5 V
CANL
CANL Dominant
Ground
RXD
CAN in TXRX Mode
CAN in Sleep Mode
(Wake-up Enable or Disable)
CAN in TXRX Mode
(Controlled by SPI Command)
Figure 21. CAN Signals in TXRX and Sleep Modes
CAN IN SLEEP MODE WITH WAKE-UP ENABLE
When the CAN interface is in Sleep mode with wake-up enable, the CAN bus traffic is detected. The CAN bus wake-up is a
pattern wake-up.
PATTERN WAKE-UP
In order to wake up the CAN interface, the following criteria must be fulfilled:
• The CAN interface wake-up receiver must receive a series of three consecutive valid dominant pulses, each of which must be
longer than 500 ns and shorter than 500 s.
• The distance between 2 pulses must be lower than 500 s.
• The three pulses must occur within a time frame of 1.0 ms.
The pattern wake-up of the 33742 CAN interface allow wake-up by any CAN message content.
Figure 22 below illustrates the CAN signals during a CAN bus Sleep state and wake-up sequence.
33742
40
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
TXD
CANH Dominant
CANH
2.5 V
CANL/CANH Recessive
CANH Dominant
CANH Dominant
CANH Dominant
Pulse # 1
Pulse # 2
Pulse # 3
CANL Dominant
CANL Dominant
CANL Dominant
CANL
CANL Dominant
Ground
CAN Bus Sleep State
RXD
CAN in TXRX Mode
Incoming CAN Message
CAN in Sleep Mode (Wake-up Enable)
WU Receiver
Min 500 ns
Max 500 s
Internal Wake-up Signal
Figure 22. CAN Bus Signal During Can Sleep State and Wake-up Sequence
Figure 23 illustrates how the wake-up signal is generated. First the CAN signal is detected by a low consumption receiver (WU
receiver). Then the signal passes through a pulse width filter, which discards the undesired pulses. The pulse must have a width
bigger than 0.5 s and smaller than 500 s to be accepted. When a pulse is discarded, the pulse counter is reset and no wakeup signal is generated. When a pulse is accepted, the pulse counter is incremented and, after three pulses, the internal wake-up
signal is asserted.
Each one of the pulses must be spaced by no more than 500 s. If not, the counter will be reset and no wake-up signal will be
generated. This is accomplished by the wake-up timeout generator. The wake-up cycle is completed (and the wake-up flag reset)
when the CAN interface is brought to CAN Normal mode.
Pulse OK
CANH
Pulse Width
Filter
CANL
WU Receiver
Counter
Latch
RST
Narrow
Pulse
+
RST
Internal Wake-up
Signal
Timeout
Timeout
Generator
Standby
Figure 23. Wake-up Functional Block Diagram
CAN WAKE-UP REPORT
The CAN wake-up reporting depend upon the low power mode the SBC is in.
If the SBC is placed into Sleep mode (VDD and V2 off), the CAN wake-up or any wake-up results in the VDD regulator turning
on, leading to turning on the MCU supply and releasing reset. If the 33742 is in Stop mode (V2 off and VDD active), the CAN
wake-up or any wake-up is signalled by a pulse on the INT output. In addition the CANWU bit is set in the CAN register.
If the SBC is in Normal or Standby mode and the CAN interface is in Sleep mode with wake-up enabled, the CAN wake-up is
reported by the CANWU bit in the CAN register.
In the event the SBC is in Normal mode and CAN Sleep mode with wake-up enabled, it is recommended that the user check
for the CANWU bit prior to placing the 33742 in Sleep or Stop mode in case bus traffic has occurred while the CAN interface was
in Sleep mode.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
41
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
After a CAN wake-up, a flag is set in the CAN register. Bit CANWU reports the CAN wake-up event while the 33742 was in
Sleep or Stop mode. This bit is set until the CAN is in placed by SPI command into TXRX mode and the CAN register can be read.
CAN BUS DIAGNOSTIC
The SBC can diagnose CANH or CANL lines short to GND, shorts to VSUP or VDD.
As illustrated in Figure 24, several single-ended comparators are implemented on the CANH and CANL bus lines. These
comparators monitor the bus voltage level in the recessive and dominant states. This information is then managed by a logic
circuit to determine if a failure has occurred and to report it. Table 11 indicates the state of the comparators in the event of bus
failure and the state of the drivers; that is, whether they are recessive or dominant.
V R5
H5
Hb
TXD
Diagnostic
Hg
VSUP (12V–14 V)
V RVB
VDD
V RVB (VSUP - 2.0 V)
V RG
CANH
V RG
CANL
Logic
Lg
Lb
L5
VDD (5.0 V)
V R5 (VDD - 0.43 V)
CANH Dominant Level (3.6 V)
Recessive Level (2.5 V)
V RG (1.75 V)
V RVB
CANL Dominant Level (1.4 V)
V R5
GND (0.0 V)
Figure 24. CAN Bus Simplified Structure
Table 11. Short to GND, Short to VSUP , and Short to 5.0 V (VDD) Detection Truth Table
Failure Description
Driver Recessive State
Driver Dominant State
Lg (Threshold 1.75 V)
Hg (Threshold 1.75 V)
Lg (Threshold 1.75 V)
Hg (Threshold 1.75 V)
No failure
1
1
0
1
CANL to GND
0
0
0
1
CANH to GND
0
0
0
0
Lb (Threshold VSUP - 2.0 V) Hb (Threshold VSUP - 2.0 V) Lb (Threshold VSUP - 2.0 V) Hb (Threshold VSUP -2.0 V)
No failure
0
0
0
0
CANL to VSUP
1
1
1
1
CANH to VSUP
1
1
0
1
L5 (Threshold VDD- 0.43 V) H5 (Threshold VDD- 0.43 V) L5 (Threshold VDD- 0.43 V)
H5
(Threshold VDD- 0.43 V)
No failure
0
0
0
0
CANL to VDD
1
1
1
1
CANH to VDD
1
1
0
1
33742
42
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
DETECTION PRINCIPLE
In the recessive state, if one of the two bus lines is shorted to GND, VDD, or VSUP, then voltage at the other line follows the
shorted line due to bus termination resistance and the high-impedance of the driver. For example, if CANL is shorted to GND,
CANL voltage is zero, and CANH voltage, as measured by the Hg comparator, is also close to zero.
In the recessive state the failure detection to GND or VSUP is possible. However, it is impossible to distinguish which bus line,
CANL or CANH, is shorted to GND or VSUP. In the dominant state, the complete diagnostic is possible once the driver is turned
on.
CAN BUS FAILURE REPORTING
CANL bus line failures (for example, CANL short to GND) is reported in the SPI register TIM1/2. CANH bus line (for example,
CANH short to VSUP) is reported in the LPC register.
In addition CAN-F and CAN-UF bits in the CAN register indicate that a CAN bus failure has been detected.
NON-IDENTIFIED AND FULLY IDENTIFIED BUS FAILURES
As indicated in Table 11, page 42, when the bus is in a recessive state it is possible to detect an error condition; however, is
it not possible to fully identify the specific error. This is called “non-identified” or “under-acquisition” bus failure. If there is no
communication (i.e., bus idle), it is still possible to warn the MCU that the SBC has started to detect a bus failure.
In the CAN register, bits D2 and D1 (CAN-F and CAN-UF, respectively) are used to signal bus failure. Bit D2 reports a bus
failure and bit D1 indicates if the failure is identified or not (bit D1 is set to logic [1} if the error is not identified).
When the detection mechanism is fully operating any bus error will be detected and reported in the TIM1/2 and LPC registers
and bit D1 will be reset to logic [0].
NUMBER OF SAMPLES FOR PROPER FAILURE DETECTION
The failure detector requires at least one cycle of recessive and dominant state to properly recognize the bus failure. The error
will be fully detected after five cycles of recessive-dominant states. As long as the failure detection circuitry has not detected the
same error for five recessive-dominant cycles, the bit “non-identified failure” (CAN-UF) will be set.
RXD PERMANENT RECESSIVE FAILURE
The purpose of this detection mechanism is to diagnose an external hardware failure at the RXD output pin and to ensure that
a permanent failure at the RXD pin does not disturb network communication.In the event RXD is shorted to a permanent high
level signal (i.e., 5.0 V), the CAN protocol module within the MCU cannot receive any incoming message. Additionally, the CAN
protocol module cannot distinguish the bus idle state and could start communication at any time. To prevent this, an RXD failure
detection, as illustrated in Figure 25 and explained below, is necessary.
TXD
Diag
TXD
Driver
Logic
2.0 V
V2
Diff Output
RXD
Driver
RXD Output
CANH
60 
Diff
CANL
GND
Sampling Sampling
Sampling
V2
RXD Sense
RXD
CANL
CANH
Sampling
RXD Short to V1
RXD Flag Latched
RXD Flag
Prop Delay
Note The RXD Flag is neither the RXPR bit in the LPC register, nor the CANF bit in the INTR register.
Figure 25. RXD Path and RXD Permanent Recessive Detection Principle
RXD FAILURE DETECTION
The SBC senses the RXD output voltage at each LOW-to-HIGH transition of the differential receiver. Excluding internal
propagation delay, RXD output should be LOW when the differential receiver is LOW. In the event RXD is shorted to 5.0 V (e.g.,
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
43
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
to VDD), RXD will be tied to a high level and the RXD short to 5.0 V can be detected at the next LOW-to-HIGH transition of the
differential receiver. Compete detection requires three samples.
When the error is detected, an error flag is latched and the CAN driver is disabled. The error is reported through the SPI
register LPC, bit RXPR.
RECOVERY CONDITION
The SBC will try to recover from a bus fault condition by sampling for a correct low level at TXD, as illustrated in Figure 26.
As soon as an RXD permanent recessive is detected, the RXD driver is deactivated and a weak pull-down current source is
activated in order to allow recovery conditions. The driver stays disabled until the failure is cleared (RXD no longer permanent
recessive) and the bus driver is activated by an SPI register command (write 1 to the CANCLR bit in the CAN register).
CANL
CANH
Diff Output
Sampling
Sampling
RXD Short to VDD
RXD Output
RXD Flag Latched
RXD no longer shorted to VDD
RXD Flag
Note RXD Flag is neither the RXPR bit in the LPC register
nor the CANF bit in INTR register.
Figure 26. RXD Recovery Conditions
TXD PERMANENT DOMINANT FAILURE
PRINCIPLE
In the event TXD is set to a permanent low level, the CAN bus is set into dominant level, and no communication is possible.
The SBC has a TXD permanent timeout detector. After timeout, the bus driver is disabled and the bus is released in a recessive
state. The TXD permanent dominant failure is reported in the TIM1 register.
RECOVERY
The TXD permanent dominant is used and activated also in case of TXD short to RXD. The recovery condition for TXD
permanent dominant (recovery means the reactivation of the CAN drivers) is done by an SPI command and is controlled by the
MCU.
The driver stays disabled until the failure is cleared (TXD no longer permanent dominant) and the bus driver is activated by
an SPI register command (write logic [1] to CANCLR bit in the CAN register).
TXD TO RXD SHORT CIRCUIT FAILURE
PRINCIPLE
In the event the TXD is shorted to RXD when an incoming CAN message is received, the RXD will be at a LOW. Consequently,
the TXD pin is LOW and drives CANH and CANL into the dominant state. The bus is stuck in dominant mode and no further
communication is possible.
DETECTION AND RECOVERY
The TXD permanent dominant timeout will be activated and release the CANL and CANH drivers. However, at the next
incoming dominant bit, the bus will be stuck again in dominant. In order to avoid this situation, the recovery from a failure
(recovery means the reactivation of the CAN drivers) is done by an SPI command and controlled by the MCU.
33742
44
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
OPERATIONAL MODES
INTERNAL ERROR OUTPUT FLAGS
There are internal error flags to signal whenever thermal protection is activated or over-current detection occurs on the CANL
or CANH pins (THERM-CUR bit). The errors are reported in the CAN register.
DEVICE FAULT OPERATION
Table 12 describes the relationship between device fault or warning and the operation of the VDD, V2, CAN, and HS interface.
Table 12. Fault / Warning
Fault / Warning
VDD
V2
CAN
HS
Battery Fail
Turn OFF
Turn OFF
Turn OFF due to V2.
No communication
OFF
VDD Temperature
Pre-warning
Warning flag only.
Leave as is
No change
No change
No change
VDD Over-temperature
Turn OFF
Turn OFF
Turn OFF due to V2.
No communication
OFF
VDD Over-current
VDD regulator enters linear
mode. VDD under-voltage
reset may occurs. VDD
over-temperature Prewarning or shutdown may
occur
Turn OFF if VDD undervoltage reset occurs
If V2 is OFF, turn OFF
and no communication
Turn OFF if VDD undervoltage reset occurs
VDD Short-circuit
VDD under-voltage reset
occurs. VDD overtemperature Pre-warning or
shutdown may occur
Turn OFF
Turn OFF due to V2.
No communication
OFF
Watchdog Reset
ON
Turn OFF
Turn OFF due to V2.
No communication
OFF
V2LOW (e.g., V2 < 4.0 V)
No change
V2 out of range
Turn OFF due to V2 low
No change
HS Over-temperature
No change
No change
No change
OFF
HS Over-current
No change
No change
No change
HS over-temperature
may occur
VSUP LOW
No change
No change
No change
No change
CAN Over-temperature
No change
No change
Disable. As soon as
temperature falls, CAN is
re-enabled automatically
No change
CAN Over-current
No change
No change
(49)
No change
No change
CANH Short to VDD
No change
No change
Communication OK
No change
CANH Short to VSUP
No change
No change
Communication OK
No change
CANL Short to GND
No change
No change
Communication OK
No change
CANL Short to VSUP
No change
No change
No change
No change
No communication
(51)
CANH Short to GND
CANL Short to VDD
No change
(50)
No change
No communication
(51)
No change
No communication
(51)
No change
Notes
49. Refer to descriptions of CANH and CANL short to GND, VDD, and VSUP elsewhere in table.
50. Peak current 150 mA during TXD dominant only. Due to loss of communication, CAN controller reaches bus OFF state. Average current
out of V2 is below 10 mA.
51. Over-current might be detected. THERM-CUR bit set in CAN register.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
45
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
LOGIC COMMANDS AND REGISTERS
SPI INTERFACE AND REGISTER DESCRIPTION
DATA FORMAT DESCRIPTION
Figure 27 illustrates an 8-bit byte corresponding to the 8 bits in a SPI register. The first three bits are used to identify the
internal SBC register address. Bit 4 is a read/write bit. The last four bits are data sent from the MCU to the SBC or read back
from the 33742 to the MCU.
The state of the MISO has no significance during the write operation. However, during a read operation the final four bits of
MISO have meaning; namely, they contain the content of the accessed register.
MISO
Bit 7 Bit 6
A2
A1
Bit 5
A0
Bit 4 Bit 3
Bit 2 Bit 1
Bit 0
R/W
D2
D0
D3
Address
D1
MOSI
Data
Note Read operation: R/W bit = logic [0]
Write operation: R/W = logic [1]
Figure 27. Data Format Description.
Table 13. Possible Reset Conditions
Condition
Name
33742 Reset
POR
Power-ON Reset
33742 Mode
Transition
NR2R
Normal Request to Reset mode
NR2N
Normal Request to Normal mode
NR2STB
Normal Request to Standby mode
33742 Mode
Definition
N2R
Normal to Reset mode
STB2R
Standby to Reset mode
STO2R
Stop to Reset mode
STO2NR
Stop to Normal Request
RESET
33742S in Reset mode
REGISTER DESCRIPTIONS
The following tables in this section describe the SPI register list and register bit meaning. Register reset values are also
described, along with the reset condition. A reset condition is the condition causing the bit to be set at the reset value.
Table 14. List of Registers
Formal Name
and Link
Comment and Use
Register
Address
MCR
$000
Mode Control Register (MCR)
on page 48
Selection for Normal, Standby, Sleep,
Stop, and Debug modes
RCR
$001
Reset Control Register (RCR)
on page 49
Configuration for reset voltage level, CAN Sleep and Stop modes
CAN
$010
CAN Register (CAN) on page
49
CAN slew rate, Sleep and Wake-up
enable/disable modes, drive enable after
failure
Write
Read
BATFAIL, general failure, VDD prewarning, and Watchdog flag
CAN wake-up and CAN failure status bits
33742
46
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 14. List of Registers
IOR
$011
Input / Output Register (IOR)
on page 50
WUR
$100
on page 51
TIM
$101
HS (high side switch) control in Normal
and Standby mode
HS over-temperature bit, VSUP, and V2
LOW status
Control of wake-up input polarity
Wake-up input and real time Lx input
state
Timing Register (TIM1 / 2) on •
page 52
TIM1: Watchdog timing control, Watch- CANL and TXD failure reporting
dog Window (WDW) or Watchdog Timeout (WTO) mode
•
TIM2: Cyclic Sense and Forced Wakeup timing selection
LPC
$110
Low Power Control Register
(LPC) on page 54
Control HS periodic activation in Sleep
and Stop modes, Forced Wake-up mode
activation, CAN-INT mode selection
CANH and RXD failure reporting
INTR
$111
Interrupt Register (INTR) on
page 56
Enable or Disable of Interrupts
Interrupt source
NOTE: For SPI Operation
In case a low pulse is asserted by the device on the RST output pin during a SPI message,
the SPI message can be corrupted. An RST low pulse is asserted in 2 cases:
Case 1: W/D refresh issue: The MCU does not perform the SPI watchdog refresh command
before the expiration of the timeout (in Normal mode or Normal Request mode and if the
“Timeout watchdog” option is selected), or the SPI watchdog refresh command is performed
in the closed window (in Normal mode and if “Window watchdog” option is selected).
Case 2: VDD undervoltage condition: VDD falls below the VDD undervoltage threshold.
Message corruption means that the targeted register address can be changed, and another
register is written. Table 15 shows the various cases and impacts on SPI register address:
Table 15. Possible Corrupted Registers In Case of RST Pulse During SPI Communication
Resulting Written register
Target
written
register
Register
MCR
RCR
CAN
IOR
Address
$000
$001
$010
$011
Register
Address
CAN
$010
IOR
$011
WUR
$100
TIM1/2
$101
LPC
$110
INTR
$111
X
X
X
X
X
X
X
X
Four registers can be corrupted: MCR, RCR, CAN, and IOR registers. As examples:
•
write to CAN register can end up as write to MCR register, or
•
write to TIM1 register can end up as write to RCR register
To avoid the previously described behavior, it is recommended to write into the MCR, RCR,
CAN, and IOR registers with the expected configuration, after each RST assertion.
In the application, a RST low pulse leads to an MCU reset and a software restart. By
applying this recommendation, all registers will be written with the expected configuration.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
47
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
MODE CONTROL REGISTER (MCR)
Tables 16 through 18 describes the various Mode Control Registers.
Table 16. Mode Control Register
MCR
R/W
D3
D2
D1
D0
$000b
W
–
MCTR2
MCTR1
MCTR0
R
BATFAIL(52)
VDDTEMP
GFAIL
WDRST
Reset Value
–
–
0
0
0
Reset Condition (Write)(53)
–
–
POR, RESET
POR, RESET
POR, RESET
Notes
52. BATFAIL bit cannot be set by SPI. BATFAIL is set when VSUP falls below 3.0 V.
53. See Table 13 page 46, for definitions of reset conditions
Table 17. Mode Control Register Control Bits
MCTR MCTR MCTR
2
1
0
33742S Mode
Description
0
0
0
Enter/Exit Debug Mode
0
0
1
Normal
0
1
0
Standby
0
0
1
1
1
0
1
1
0
Stop, Watchdog
To enter/exit Debug Mode, refer to detailed description in Debug Mode: Hardware and
Software Debug with the 33742, page 34.
–
–
OFF(54)
–
(54)
–
Stop, Watchdog ON
Sleep(55)
1
0
1
Normal
1
1
0
Standby
1
1
1
Stop
–
No Watchdog running. Debug mode.
Notes
54. Watchdog ON or OFF depends on RCR bit D3.
55. Before entering Sleep mode, BATFAIL bit in MCR must be previously cleared (MCR read operation), and NOSTOP bit in RCR must be
previously set to logic [1].
Table 18. Mode Control Register Status Bits
Name
BATFAIL
VDDTEMP
GFAIL
WDRST
Logic
Description
0
VSUP was not below VBF.
1
VSUP has been below VBF.
0
No over-temperature pre-warning.
1
Temperature pre-warning on VDD regulator (bit latched).
0
No failure.
1
CAN Failure or HS over-temperature or V2 low.
0
No watchdog reset occurred.
1
Watchdog reset occurred.
33742
48
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
RESET CONTROL REGISTER (RCR)
Tables 19 and 20 contain various Reset Control Register information.
Table 19. Reset Control Register
RCR
R/W
D3
D2
D1
D0
WDSTOP
NOSTOP
CAN SLEEP
RSTTH
–
1
0
0
0
–
POR, RESET, STO2NR
POR, NR2N, NR2STB
POR, NR2N, NR2STB
POR
W
$001b
R
Reset Value
(56)
Reset Condition (Write)
Notes
56. See Table 13 page 46, for definitions of reset conditions.
Table 20. Reset Control Register Control Bits
Name
Logic
WDSTOP
NOSTOP
CAN SLEEP
RSTTH
Description
0
No Watchdog in Stop mode.
1
Watchdog runs in Stop mode.
0
Device cannot enter Sleep mode.
1
Sleep mode allowed. Device can enter Sleep mode.
0
CAN Sleep mode disable (despite D0 bit in CAN register).
1
CAN Sleep mode enabled (in addition to D0 in CAN register).
0
Reset Threshold 1 selected (typ 4.6 V).
1
Reset Threshold 2 selected (typ 4.2 V).
CAN REGISTER (CAN)
Tables 21 through 24 contain the information on the CAN register. Table 21 describes control of the high-speed CAN module,
mode, slew rate, and wake-up.
Table 21. CAN Register
CAN
$010b
Reset Value
Reset Condition (Write)
(57)
R/W
D3
D2
D1
D0
W
CANCLR
SC1
SC0
MODE
R
CANWU
CAN-F
CAN-UF
THERM-CUR
–
0
0
0
1
–
POR
POR
POR
NR2N, STB2N
Notes
57. See Table 13, page 46, for definitions of reset conditions.
Table 22. CANCLR Control Bits
Logic
Description
0
No effect.
1
Re-enables CAN driver after TXD permanent dominant or RXD permanent recessive failure occurred. Failure
recovery conditions must occur to re-enable.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
49
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
HIGH-SPEED CAN TRANSCEIVER MODES
The MODE bit (D0) controls the state of the CAN interface, TXRX or Sleep mode (Table 23). SC0 bit (D1) defines the slew
rate when the CAN module is in TXRX, and it controls the wake-up option (wake-up enable or disable) when the CAN module is
in Sleep mode.
Table 23. CAN High Speed Transceiver Modes
SC1
SC0
MODE
CAN Mode
(Pass 1.1)
0
0
0
CAN TXRX, Slew Rate 0
0
1
0
CAN TXRX, Slew Rate 1
1
0
0
CAN TXRX, Slew Rate 2
1
1
0
CAN TXRX, Slew Rate 3
x
1
1
CAN Sleep and CAN Wake-up Disable
x
0
1
CAN Sleep and CAN Wake-up Enable
x = Don’t care.
Table 24. CAN Register Status Bits
Name
Logic
CANWU
CAN-F
CAN-UF
THERM-CUR
Description
0
No CAN wake-up occurred.
1
CAN wake-up occurred.
0
No CAN failure.
1
CAN failure(58).
0
Identified CAN failure(58).
1
Non-identified CAN failure.
0
No over-temperature or over-current on CANH or CANL drivers.
1
Over-temperature or over-current on CANH or CANL drivers.
Notes
58. Error bits are latched in the CAN register.
INPUT / OUTPUT REGISTER (IOR)
Tables 25 through 27 contain the Input / Output Register information. Table 26 provides information about information HS
control in Normal and Standby modes, while Table 27 provides status bit information.
Table 25. Input / Output Register
IOR
$011b
Reset Value
Reset Condition (Write)
(59)
R/W
D3
D2
D1
D0
W
–
HSON
–
–
R
V2LOW
HSOT
VSUPLOW
DEBUG
–
–
0
–
–
–
–
POR
–
–
Notes
59. See Table 13, page 46, for definitions of reset conditions.
33742
50
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 26. HSON Control Bits
Logic
HS State
0
HS OFF, in Normal and Standby modes.
1
HS ON, in Normal and Standby modes.(60)
Notes
60. When HS is turned OFF due to an over-temperature condition, it can be turned ON again by setting the appropriate control bit to 1. Error
bits are latched in the IOR register.
Table 27. Input / Output Register Status Bits
Name
Logic
V2LOW
HSOT
VSUPLOW
DEBUG
Description
0
V2LTH > 4.0V.
1
V2LTH < 4.0V.
0
No HS over-temperature.
1
HS over-temperature.
0
VBF(EW) > 5.8V.
1
VBF(EW) < 5.8V.
0
SBC not in Debug mode.
1
SBC accepts command to go to Debug modes (no Watchdog).
WAKE-UP REGISTER (WUR)
Tables 28 through 30 contain the Wake-up Register information. Local wake-up inputs L0 : L3 can be used in both Normal and
Standby modes as port expander, as well as for waking up the SBC from Sleep or Stop modes (Table 28).
Table 28. Wake-up Register
WUR
$100b
Reset Value
(61)
Reset Condition (Write)
R/W
D3
D2
D1
D0
W
LCTR3
LCTR2
LCTR1
LCTR0
R
L3WU
L2WU
L1WU
L0WU
–
0
0
0
0
–
POR, NR2R, N2R, STB2R, STO2R
Notes
61. See Table 13, page 46, for definitions of reset conditions.
Wake-up inputs can be configured by pair. L0 and L1 can be configured together, and L1 and L2, and L2 and L3 can be
configured together (Table 29).
Table 29. Wake-up Register Control Bits
LCTR3
LCTR2
LCTR1
LCTR0
L0 L1 : L1 L2 Config
L2 L3 : L3 L4 Config
x
x
0
0
Inputs Disabled
–
x
x
0
1
High Level Sensitive
x
x
1
0
Low Level Sensitive
x
x
1
1
Both Level Sensitive
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
51
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 29. Wake-up Register Control Bits (continued)
0
0
x
x
–
Inputs Disabled
0
1
x
x
High Level Sensitive
1
0
x
x
Low Level Sensitive
1
1
x
x
Both Level Sensitive
x = Don’t care.
Table 30. Wake-up Register Status Bits (62)
Name
Logic
Description
L3WU
0 or 1
L2WU
0 or 1
If bit = 1, wake-up occurred from Sleep or Stop modes; if bit = 0, no wake-up has
occurred.
L1WU
0 or 1
L0WU
0 or 1
When device is in Normal or Standby mode, bit reports the State on Lx pin (LOW
or HIGH) (0 = Lx LOW, 1 = Lx HIGH)
Notes
62. WUR status bits have two functions. After SBC wake-up, they indicate the wake-up source; for example, L2WU set at logic [1] if wakeup source is L2 input. After SBC wake-up and once the WUR register has been read, status bits indicate the real-time state of the Lx
inputs (1 = Lx is above threshold, 0 = Lx input is below threshold). If after a wake-up from Lx input a watchdog timeout occurs before the
first reading of the WUR register, the LxWU bits are reset. This can occur only if the SBC was in Stop mode.
TIMING REGISTER (TIM1 / 2)
Tables 31 through 35 contain the Timing Register information. The TIM register is composed of two sub registers:
• TIM1 — Controls the watchdog timing selection as well as either the watchdog window or the watchdog timeout option
(Figure 28 and Figure 29, respectively). TIM1 is selected when bit D3 is 0 (Table 31). Watchdog timing characteristics are
described in Table 32.
• TIM2 — Selects an appropriate timing for sensing the wake-up circuitry or cyclically supplying devices by switching the HS on
or off. TIM2 is selected when bit D3 is 1 (Table 33). Figure 30, page 54, describes HS operation when cyclic sense is selected
Cyclic sense timing characteristics are described in Table 35, page 54.
Both subregisters also report the CANL and TXD diagnostics.
Table 31. TIM1 Timing and CANL Failure Diagnostic Register
TIM1
R/W
D3
D2
D1
D0
$101b
W
0
WDW
WDT1
WDT0
R
CANL2VDD
CANL2BAT
CANL2GND
TXPD
Reset Value
–
–
0
0
0
Reset Condition (Write)(63)
–
–
POR, RESET
POR, RESET
POR, RESET
Notes
63. See Table 13, page 46, for definitions of reset conditions.
33742
52
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 32. TIM1 Control Bits
WDW
WDT1
WDT0
Timing (ms typ)
Parameter
0
0
0
9.75
Watchdog Period 1
0
0
1
45
Watchdog Period 2
0
1
0
100
Watchdog Period 3
0
1
1
350
Watchdog Period 4
1
0
0
9.75
Watchdog Period 1
1
0
1
45
Watchdog Period 2
1
1
0
100
Watchdog Period 3
1
1
1
350
Watchdog Period 4
Window Closed
No Watchdog Clear Allowed
Watchdog Timing x 50%
Description
No Window Watchdog
Watchdog Window enabled
(Window length is half the
Watchdog Timing).
Window Open for Watchdog Clear
Watchdog Timing x 50%
Watchdog Period
(Watchdog Timing Selected by TIM1 Bit WDW =1)
Figure 28. Window Watchdog
Window Open for Watchdog Clear
Watchdog Period
(Watchdog Timing Selected by TIM1 Bit WDW = 0)
Figure 29. Timeout Watchdog
Table 33. Timing Register Status Bits
Name
CANL2VDD
CANL2BAT
CANL2GND
TXPD
Logic
Failure Description
0
No CANL short to VDD.
1
CANL short to VDD.
0
No CANL short to VSUP .
1
CANL short to VSUP .
0
No CANL short to GND.
1
CANL short to GND.
0
No TXD dominant.
1
TXD dominant.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
53
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 34. TIM2 Timing and CANL Failure Diagnostic Register
TIM2
$101b
Reset Value
(64)
Reset Condition (Write)
R/W
D3
D2
D1
D0
W
1
CSP2
CSP1
CSP0
R
CANL2VDD
CANL2BAT
CANL2GND
TXPD
–
–
0
0
0
–
–
POR, RESET
POR, RESET
POR, RESET
Notes
64. See Table 13, page 46, for definitions of reset conditions.
Cyclic Sense Timing,
ON Time
HS ON
HS
Cyclic Sense Timing, OFF Time
10 s
HS OFF
Lx Sampling Point
Sample
time
Figure 30. HS Operation When Cyclic Sense Is Selected
Table 35. TIM2 Control Bits
Parameter
CSP2
CSP1
CSP0
Cyclic Sense Timing (ms)
0
0
0
4.6
Cyclic Sense/FWU Timing 1
0
0
1
9.25
Cyclic Sense/FWU Timing 2
0
1
0
18.5
Cyclic Sense/FWU Timing 3
0
1
1
37
Cyclic Sense/FWU Timing 4
1
0
0
74
Cyclic Sense/FWU Timing 5
1
0
1
95.5
Cyclic Sense/FWU Timing 6
1
1
0
191
Cyclic Sense/FWU Timing 7
1
1
1
388
Cyclic Sense/FWU Timing 8
LOW POWER CONTROL REGISTER (LPC)
Tables 36 through 40 contain the Low Power Control Register information. The LPC register controls:
• The state of HS in Stop and Sleep modes (HS permanently OFF or HS cyclic).
• Enable or disable of the forced wake-up function (SBC automatic wake-up after time spent in Sleep or Stop modes; time is
defined by the TIM2 sub register).
• Enable or disable the sense of the wake-up inputs (Lx) at the sampling point of the Cyclic Sense period (LX2HS bit). (Refer to
Reset Control Register (RCR) on page 49 for details of the LPC register setup required for proper cyclic sense or direct wakeup operation.
The LPC register also reports the CANH and RXD diagnostic.
33742
54
Analog Integrated Circuit Device Data
Freescale Semiconductor
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
Table 36. Low Power Control Register
LPC
R/W
$110b
Reset Value
(65)
Reset Condition (Write)
D3
D2
D1
D0
W
LX2HS
FWU
CAN-INT
HSAUTO
R
CANH2VDD
CANH2BAT
CANH2GND
RXPR
–
0
0
0
0
–
POR, NR2R, N2R,
STB2R, STO2R
POR, NR2R, N2R,
STB2R, STO2R
POR, NR2R, N2R,
STB2R, STO2R
POR, NR2R, N2R,
STB2R, STO2R
Notes
65. See Table 13, page 46, for definitions of reset conditions.
Table 37. LX2HS Control Bits
Logic
Wake-up Inputs Supplied by HS
0
No.
1
Yes. Lx inputs sensed at sampling point.
Table 38. HSAUTO Control Bits
Logic
Auto-timing HS in Sleep and Stop modes
0
OFF.
1
ON, HS Cyclic, period defined in TIM2 subregister.
Table 39. CAN-INT Control Bits
Logic(66)
Description
0
Interrupt as soon as CAN bus failure detected.
1
Interrupt when CAN bus failure detected and fully identified.
Notes
66. If CAN-INT is at logic [0], any undetermined CAN failure will be latched in the CAN register (bit D1: CAN-UF) and can be accessed by
SPI (refer to CAN Register (CAN) on page 49). After reading the CAN register or setting CAN-INT to logic [1], it will be cleared
automatically. The existence of CAN-UF always has priority over clearing, meaning that a further undetermined CAN failure does not
allow clearing the CAN-UF bit.
Table 40. LPC Status Bits
Name
CANH2VDD
CANH2BAT
CANH2GND
RXPR
Logic
Failure Description
0
No CANH short to VDD.
1
CANH short to VDD.
0
No CANH short to VSUP.
1
CANH short to VSUP.
0
No CANH short to GND.
1
CANH short to GND.
0
No RXD permanent recessive.
1
RXD permanent recessive.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
55
FUNCTIONAL DEVICE OPERATION
LOGIC COMMANDS AND REGISTERS
INTERRUPT REGISTER (INTR)
Tables 41 through 43 contain the Interrupt Register information. The INTR register allows masking or enabling the interrupt
source. A read operation identifies the interrupt source. Table 43 provides status bit information. The status bits of the INTR
register content are copies of the IOR, CAN, TIM, and LPC registers status content. To clear the Interrupt Register bits, the IOR,
CAN, TIM, and/or LPC registers must be cleared (read register) and the recovery condition must occur. Errors bits are latched
in the CAN register and the IOR register.
Table 41. Interrupt Register
INTR
R/W
$111b
Reset Value
(68)
Reset Condition (Write)
D3
D2
(67)
D1
D0
V1TEMP
CANF
W
VSUPLOW
R
VSUPLOW
HSOT
V1TEMP
CANF
–
0
0
0
0
–
POR, RST
POR, RST
POR, RST
POR, RST
HSOT-V2LOW
Notes
67. If only HSOT - V2LOW interrupt is selected (only bit D2 set in INTR register), reading INTR register bit D2 leads to two possibilities:
1. Bit D2 = 1: Interrupt source is HSOT.
2. Bit D2 = 0: Interrupt source is V2LOW.
HSOT and V2LOW bits status are available in the IOR register.
68. See Table 13, page 46, for definitions of reset conditions.
Table 42. Interrupt Register Control Bits
Name
CANF
Description
Mask bit for CAN failures.
VDDTEMP
Mask bit for VDD medium temperature (pre-warning).
HSOT - V2LOW
Mask bit for HS over-temperature AND V2LTH < 4.0 V.
VSUPLOW
Mask bit for VBF(EW) < 5.8 V.
When the mask bit is set, the INT pin goes LOW if the appropriate condition occurs. Upon a wake-up condition from Stop mode
due to over-current detection (IDDS-WU1 or IDDS-WU2), an INT pulse is generated; however, INTR register content remains at 0000
(not bit set into the INTR register).
Table 43. Interrupt Register Status Bits
Name
VSUPLOW
HSOT
VDDTEMP
CANF
Logic
Description
0
No VBF(EW) < 5.8 V.
1
VBF(EW) < 5.8 V.
0
No HS over-temperature.
1
HS over-temperature.
0
No VDD medium temperature (pre-warning).
1
VDD medium temperature (pre-warning).
0
No CAN failure.
1
CAN failure.
33742
56
Analog Integrated Circuit Device Data
Freescale Semiconductor
TYPICAL APPLICATIONS
TYPICAL APPLICATIONS
SBC POWER SUPPLY
The 33742 is supplied from the battery line. A serial diode is necessary to protect the device against negative transient pulses
and from reverse battery. This is illustrated in Figure 31.
VPWR
Q1
D1
VSUP
Rp
R1
SW1
to L1
C1
C2
33742
R5
VSUP Monitor
Dual Voltage Regulator
VDD Monitor
5.0V/200mA
V2CTRL
HS
Control
C6
HS
L0
Rp
R2
SW2
L1
to L1
L2
Programmable
Wake-up Input
L3
C7
Mode Control
Oscillator
V2
V2
VDD
C3
C4
Interrupt
Watchdog
Reset
INT
WDOG
RST
SPI Interface
MOSI
SCLK
MISO
C10
C5
MCU
CS
CANH
CANL
1.0 Mbps CAN
Physical Interface
SW3
TXD
RXD
GND
R3
Rd
Internal
Module
Supply
to L2
C8
SW4
Safe Circuitry
Clamp (1)
R4
Rd
to L3
C9
Connector
Legend
D1: Example: 1N4002 type
Q1: MJD32C
R1, R2, R3, R4: 10k
Rp, Rd: Example: 1.0k depending on switch type.
R5: 2.2 k
C1: 10 F
C2: 100 nF
C3: 47 F
C4: 100 nF
C5: 47 F tantalum or 100 F chemical
C6, C7, C8, C9, C10: 100 nF
(1) Clamp circuit to ensure max ratings for HS (HS from
- 0.3V to VSUP + 0.3) are respected.
Figure 31. SBC Typical Application Schematic
VOLTAGE REGULATOR
The SBC contains two 5.0 V regulators: a V1 regulator, fully integrated and protected, and a V2 regulator, which operates with
an external ballast transistor.
33742
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Freescale Semiconductor
57
TYPICAL APPLICATIONS
VDD REGULATOR
The VDD regulator provides 5.0 V output, 2.0% accuracy with current capability of 200 mA max. It requires external decoupling
and stabilizing capacitors. The minimum recommended values are as follows:
•
•
•
•
C4: 100 nF
C3: 10 F < C3 <22 F, ESR < 1.0 or
C3: 22 F < C3 <47 F, ESR < 5.0 or
C3: 47 F, ESR < 10 
V2 REGULATOR: OPERATING WITH EXTERNAL BALLAST TRANSISTOR
The V2 regulator is a tracking regulator of the VDD output. Its accuracy relative to VDD is ±1.0%. It requires external
decoupling and stabilizing capacitors.
The recommended value are as follows:
• 22 F, ESR < 5.0 
• 47 F, ESR < 10 
The V2 pin has two functions: it is a sense input for the V2 regulator and is a 5.0 V power supply input to the CAN interface.
With respect to ballast transistor selection, either PNP or PMOS transistors may be used. A resistor between base and emitter
(or source and drain) is necessary to ensure proper operation and optimized performances. Recommended bipolar transistor is
MJD32C.
V2 REGULATOR: OPERATION WITHOUT BALLAST TRANSISTOR
The external ballast transistor is optional. If the application does not requires more than the maximum output current capability
of the VDD regulator, then the ballast transistor can be omitted. The thermal aspects must be analyzed as well.
The electrical connection is illustrated in Figure 32.
No Connect
33742
VPWR
V2CTRL
VSUP
C1
V2
Components List
VDD
C2
C3
C1: 22 F
C4
VDD
RST
RESET
MCU
C2: 100 nF
C3: >10 F
C4: 100 nF
Figure 32. V2 Regulator Electrical Connection
FAILURE ON VDD, WDOG, RESET, AND INT PINS
The paragraphs below describe the behavior of the device and of the INT, RST, and WDOG pins at power-up and under failure
of the VDD regulator.
POWER-UP AND SBC ENTERING NORMAL OPERATION
After power-up the 33742 enters Normal Request mode (CAN interface is in TXRX mode): VDD is on and V2 is off.
After 350 ms if no watchdog is written (no TIM1 register write), a reset occurs and the 33742 returns to Normal Request mode.
During this sequence WDOG is active (low level).
Once watchdog is written, the 33742 goes to Normal mode: VDD is still on and V2 turns on, WDOG is no longer active, and
the RST pin is HIGH. If watchdog is not refreshed, the 33742 generates a reset and returns to Normal Request mode. Figure 33,
illustrates the operation.
33742
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Analog Integrated Circuit Device Data
Freescale Semiconductor
TYPICAL APPLICATIONS
Missing Watchdog Refresh
Watchdog Refresh
VDD
SPI (CS)
Watchdog
Refresh
WD
RST
INT
350ms
SBC in
Reset
mode
SBC in Normal Request
& Reset modes
SBC in Normal
mode
SBC in Normal
Request & Reset
mode
Reset each 350 ms
Figure 33. Power up sequence, No W/D write at first
POWER UP AND VDD GOING LOW WITH STOP MODE AS DEFAULT LOW POWER MODE IS SELECTED
The first part of Figure 34 is identical to Figure 33. If VDD is pulled below VDD under-voltage reset (typ 4.6 V), say by an overcurrent or short-circuit (for instance, short to 4.0 V), and if a low power mode previously selected was Stop mode, the 33742
enters Reset mode (RST pin is active). The WDOG pin stays HIGH, but the high level (Voh) follows V1 level. The INT pin goes
LOW.
When the VDD overload condition is removed, the 33742 restarts in Normal Request mode.
Under-voltage at VDD (VDD < VRSTTH)
Watchdog Refresh
VDD
350 ms
SPI (CS)
WD
RST
INT
SBC in
Reset
mode
SBC in Normal Request
& Reset modes
SBC in Normal
mode
SBC in Normal
Reset mode
Reset each 350 ms
Figure 34. Under-voltage on VDD
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
59
TYPICAL APPLICATIONS
POWER-UP AND VDD GOING LOW WITH SLEEP MODE AS DEFAULT LOW POWER MODE IS SELECTED
The first part of Figure 35 is identical to Figure 34. If VDD is pulled below the VDD under-voltage reset (typ 4.6 V), say by an
over-current or short-circuit (for instance, short to 4.0 V), and if the low power mode previously selected was Sleep mode and if
the BATFAIL flag has been cleared, the 33742 enters in Reset mode for a time period of 100 ms. The WDOG pin stays HIGH,
but the high level (VOH) follows VDD level. The RST and INT pins are low. After 100 ms the 33742 goes into Sleep mode, and
the VDD and V2 are off.
Figure 35 shows an example wherein VDD is shorted to 4.0 V, and after 100 ms the 33742 enters Sleep mode.
.
Under-voltage at VDD
Watchdog Refresh
VDD
SPI (CS)
100 ms
WD
RST
Reset mode
INT
SBC in
Reset
mode
SBC in Normal Request
& Reset modes
SBC in Sleep mode
SBC in Normal
mode
SBC in Reset mode for
100ms, then enter
Sleep mode
Reset each 350 ms
Figure 35. Under-voltage at VDD. Sleep mode selected.
CANH (33742)
CANH
CH
R5
CANL (33742)
CANL
CL
CAN Connector
Legend
R5: 60 
CL, CH: 220 pF
Figure 36. CAN Bus Standard Termination
CANH
CANH (33742)
R6
CH
R7
CANL (33742)
CANL
CAN Connector
Legend
R6, R7: 30 
CL, CH: 220 pF
CS: > 470 pF
CL
CS
Figure 37. CAN Bus Split Termination
33742
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Analog Integrated Circuit Device Data
Freescale Semiconductor
PACKAGING
PACKAGE AND THERMAL CONSIDERATIONS
PACKAGING
PACKAGE AND THERMAL CONSIDERATIONS
The 33742 SBC is a standard surface mount 28-pin SOIC wide body. In order to improve the thermal performances of the
SOIC package, eight of the 28 pins are internally connected to the package lead frame for heat transfer to the printed circuit
board.
PACKAGING DIMENSIONS
Important For the most current revision of the package, visit www.freescale.com and perform a keyword search on the
98ASB42345B drawing number below. Dimensions shown are provided for reference ONLY.
33742
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Freescale Semiconductor
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PACKAGING
PACKAGING DIMENSIONS
33742
62
Analog Integrated Circuit Device Data
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PACKAGING
PACKAGING DIMENSIONS
33742
Analog Integrated Circuit Device Data
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63
PACKAGING
PACKAGING DIMENSIONS
33742
64
Analog Integrated Circuit Device Data
Freescale Semiconductor
PACKAGING
PACKAGING DIMENSIONS
33742
Analog Integrated Circuit Device Data
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65
PACKAGING
PACKAGING DIMENSIONS
33742
66
Analog Integrated Circuit Device Data
Freescale Semiconductor
ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 2.0)
ADDITIONAL DOCUMENTATION
33742SOICW
THERMAL ADDENDUM (REV 2.0)
Introduction
This thermal addendum is provided as a supplement to the MC33742
technical datasheet. The addendum provides thermal performance
information that may be critical in the design and development of system
applications. All electrical, application, and packaging information is
provided in the data sheet.
28-PIN SOICW
Packaging and Thermal Considerations
The MC33742 is offered in a 28 pin SOICW exposed pad, single die
package. There is a single heat source (P), a single junction temperature
(TJ), and thermal resistance (RJA).
TJ
=
RJA
.
P
The stated values are solely for a thermal performance comparison of
one package to another in a standardized environment. This methodology
is not meant to and will not predict the performance of a package in an
application-specific environment. Stated values were obtained by
measurement and simulation according to the standards listed below.
EG SUFFIX (PB-FREE)
98ASB42345B
28-PIN SOICW
Note For package dimensions, refer to
98ASB42345B.
Standards
Table 44. Thermal Performance Comparison
Thermal Resistance
Notes:
1.
2.
3.
4.
5.
[C/W]
RJA(1), (2)
41
RJB(2), (3)
10
RJA(1), (4)
68
RJC(5)
220
Per JEDEC JESD51-2 at natural convection, still air condition.
2s2p thermal test board per JEDEC JESD51-7.
Per JEDEC JESD51-8, with the board temperature on the center trace near the center lead.
Single layer thermal test board per JEDEC JESD51-3.
Thermal resistance between the die junction and the package top surface; cold plate attached to the package top surface and
remaining surfaces insulated.
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
67
ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 2.0)
1.0
0.2
1.0
0.2
* All measurements
are in millimeters
28 Pin SOICW
1.27 mm Pitch
16.0 mm x 7.5 mm Body
Figure 38. Surface Mount for SOIC Wide Body non-Exposed Pad
RXD
TXD
VDD
RST
INT
GND
GND
GND
GND
V2
V2CTRL
VSUP
HS
L0
1
28
2
27
3
26
4
25
5
24
6
23
7
22
8
21
9
20
10
19
11
18
12
17
13
16
14
15
WDOG
CS
MOSI
MISO
SCLK
GND
GND
GND
GND
CANL
CANH
L3
L2
L1
A
33742 Pin Connections
28-Pin SOICW
1.27 mm Pitch
18.0 mm x 7.5 mm Body
Figure 39. Thermal Test Board
33742
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Analog Integrated Circuit Device Data
Freescale Semiconductor
ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 2.0)
Device on Thermal Test Board
Material:
Single layer printed circuit board
FR4, 1.6 mm thickness
Cu traces, 0.07 mm thickness
Outline:
80 mm x 100 mm board area,
including edge connector for thermal
testing
Area A:
Cu heat-spreading areas on board
surface
Ambient Conditions:
Natural convection, still air
Table 45. Thermal Resistance Performance
A [mm²] RθJA [°C/W]
68
0
52
300
47
600
RJAis the thermal resistance between die junction and ambient air.
Thermal Resistance [ºC/W]
80
70
60
50
40
30
x
20
RJA
10
0
0
300
Heat spreading area A [mm²]
600
Figure 40. Device on Thermal Test Board RJA
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Analog Integrated Circuit Device Data
Freescale Semiconductor
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ADDITIONAL DOCUMENTATION
THERMAL ADDENDUM (REV 2.0)
Thermal Resistance [ºC/W]
100
10
x RJA
1
0.1
1.00E-03
1.00E-02
1.00E-01 1.00E+00 1.00E+01 1.00E+02 1.00E+03 1.00E+04
Time[s]
Figure 41. Transient Thermal Resistance RJA,
1 W Step response, Device on Thermal Test Board Area A = 600 (mm2)
33742
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Analog Integrated Circuit Device Data
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REVISION HISTORY
REVISION HISTORY
REVISION
DATE
DESCRIPTION OF CHANGES
3
2/2006
•
•
Converted to Freescale format
Implemented Revision History page
4
6/2006
•
•
Added Thermal Addendum (Rev. 1.0)
Changed Data Sheet from “Advanced” to “Final”
5
8/2006
•
Added MCZ33742EG/R2 and MCZ33742SEG/R2 to the Ordering Information block
6
8/2006
•
Replaced label for Logic Inputs to Logic Signals (RXD, TXD, MOSI, MISO, CS, SCLK, RST, WDOG, and
INT) on page 7
7
10/2006
•
•
Removed all references to the 54 pin package.
Removed Peak Package Reflow Temperature During Reflow (solder reflow) parameter from Maximum
Ratings on page 7. Added note with instructions from www.freescale.com.
8
2/2007
•
•
Revised () and (),
Restated notes in Maximum Ratings on page 7
9
3/2007
•
Text corrections to the included thermal addendum
10
5/2007
•
•
•
Added EP 48 pin QFN package
Added 98ARH99048A Package drawing
Added PCZ33742EP/R2 to the ordering information
11
6/2008
•
•
•
•
•
•
Made changes defining RXD as a push-pull structure on page 15, 22, 38, and 39
Updated figures Figure 12 and Figure 25
Added provisions of differentiation for 28-pin SOIC and 48-pin QFN for ESD Capability, Human Body
Model(1) on page 7, Watchdog Period Normal and Standby Modes on page 17, and Normal Request
Mode Timeout on page 17
Update the Freescale format and style to the current standards
Added the Functional Internal Block Description section
Changed PCZ33742EP/R2 to MC33742EP/R2 in the ordering information
2/2011
•
Added MC33742PEG/R2, MC33742SPEG/R2, and MC33742PEP/R2 to the ordering information
13.0
7/2011
•
•
Updated Freescale form and style
Removed MCZ33742EG/R2, MC33742SDW/R2, MCZ33742SEG/R2, and MCZ33742EP/R2 from the
ordering information
14.0
6/2013
•
•
Added a For SPI Operation on page 47
Updated document properties
15.0
12/2014
•
Updated case outline (changed 98ASA10825D to 98ASA00757D) as per PCN 16557
12.0
33742
Analog Integrated Circuit Device Data
Freescale Semiconductor
71
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may vary over time. All operating parameters, including “typicals,” must be validated for each customer application by
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© 2014 Freescale Semiconductor, Inc.
Document Number: MC33742
Rev. 15.0
12/2014
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