STMICROELECTRONICS L9822N

L9822N
®
OCTAL SERIAL SOLENOID DRIVER
.
..
..
.
.
..
EIGHT LOW RDSon DMOS OUTPUTS
(0.5Ω AT IO = 1A @ 25°C VCC = 5V± 5%)
8 BIT SERIAL INPUT DATA (SPI)
8 BIT SERIAL DIAGNOSTIC OUTPUT FOR
OVERLOAD AND OPEN CIRCUIT CONDITIONS
OUTPUT SHORT CIRCUIT PROTECTION
CHIP ENABLE SELECT FUNCTION (active low)
INTERNAL 35V CLAMPING FOR EACH OUTPUT
CASCADABLE WITH ANOTHER OCTAL
DRIVER
LOW QUIESCENT CURRENT (10mA MAX.)
PACKAGE Power SO20
DESCRIPTION
The L9822N is an octal low side solenoid driver
rea lized in Multipower-BCD technology particularly
suited for driving lamps, relays and solenoids in
MULTIPOWER BCD TECHNOLOGY
PowerSO20
ORDERING NUMBER: L9822N
automotive environment. The DMOS outpts
L9822N has a very low power consumption.
Data is transmitted serially to the device using the
Serial Peripheral Interface (SPI) protocol.
The L9822N features the outputs status monitoring
function.
BLOCK DIAGRAM
October 2003
1/9
L9822N
PIN CONNECTIONS (top view)
GND
1
20
GND
SO
2
19
SI
VCC
3
18
SCLK
RESET
4
17
CE
OUT7
5
16
OUT0
OUT6
6
15
OUT1
OUT5
7
14
OUT2
OUT4
8
13
OUT3
N.C.
9
12
N.C.
GND
10
11
GND
D94AT119A
ABSOLUTE MAXIMUM RATINGS
Symbol
VCC
VO
II
Tj, Tstg
DC Logic Supply
Parameter
– 0.7
Value
7
Unit
V
Output Voltage
Input Transient Current
(CE, SI, SCLK, RESET, SO) :
Duration Time t = 1s,
VI < 0
VI > VCC
Junction and Storage Temperature Range
– 0.7
40
V
+ 25
mA
mA
150
°C
– 25
– 40
THERMAL DATA
Symbol
Rth j-case
Parameter
Thermal Resistance Junction-Case
Max.
Value
1.5
°C/W
Rth j-amb
Thermal Resistance Junction-Ambient
Max.
60
°C/W
2/9
Unit
L9822N
PIN DESCRIPTION
VCC
Logic supply voltage - nominally 5V
GROUND
Device Ground. This ground applies for the logic circuits as well as the power output stages.
RESET
Asynchronous reset for the output stages, the parallel latch and the shift register inside the
L9822NSP. This pin is active low and it must not be
left floating. A power on clear function may be implemented connecting this pin to VCC with an external resistor and to ground with an external capacitor.
CE
Chip Enable. Data is transferred from the shift registers to the outputs on the rising edge of this signal.
The falling edge of this signal sets the shift register
with the output voltage sense bits coming from the
output stages. The output driver for the SO pin is enabled when this pin is low.
SO
Serial Output. This pin is the serial output from the
shift register and it is tri-stated when CE is high. A
high for a data bit on this pin indicates that the par-
ticular output is high. A low on this pin for a data bit
indicates that the output is low.
Comparing the serial output bits with the previous
serial input bits the external microcontroller implements the diagnostic data supplied by the L9822.
SI
Serial Input. This pin is the serial data input. A high
on this pin will program a particular output to be OFF,
while a low will turn it ON.
SCLK
Serial Clock. This pin clocks the shift register. New
SO data will appear on every rising edge of this pin
and new SI data will be latched on every SCLK’s falling edge into the shift register.
OUTPUTS 00-07
Power output pins. The input and output bits corresponding to 07 are sent and received first via the SPI
bus and 00 is the last.
The outputs are provided with current limiting and
voltage sense functions for fault indication and protection. The nominal load current for these outputs
is 500mA. The outputs also have on board clamps
set at about 36V for recirculation of inductive load
current.
ELECTRICAL CHARACTERISTICS (VCC = 5V ± 5%. Tj = – 40 to 125°C ; unless otherwise speciifed)
Symbol
VOC
EOC
IOFF
RDSon
Parameter
Output Clamping Volt.
Out. Clamping Energy
Out. Leakage Current
Test Conditions
IO = 0.5A, Output Programmed OFF
IO = 0.5A, When ON
VO = 24V, Output Progr. OFF
On Resistance
Output Progr. ON
IO = 0.5A
IO = 0.75A
IO = 1A
With Fault Reset Disabled
Min.
30
20
Typ.
35
0.53
0.53
0.53
Max.
40
1
Unit
V
mJ
mA
1
1
1
Ω
Ω
Ω
tPHL
Turn-on Delay
IO = 500mA
No Reactive Load
10
µs
tP
Turn-off Delay
IO = 500mA
No Reactive Load
10
µs
Fault Refer. Voltage
Output Progr. OFF
Fault detected if VO > VOREF
See fig. 3
1.6
2
V
75
250
µs
1.0
V
VOREF
tUD
VOFF
Fault Reset Delay
(after CE L to H
transition)
Output OFF Voltage
Output Pin Floating.cOutput Progr. OFF,
3/9
L9822N
ELECTRICAL CHARACTERISTICS (Continued)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
INPUT BUFFER (SI, CE, SCLK and RESET pins)
VT–
Threshold Voltage at
Falling Edge
0.2VCC
VT+
Threshold Voltage at
Rising Edge
VH
II
Hysteresis Voltage
Input Current
VT+ – VT–
VCC = 5.25V, 0 < VI < VCC
CI
Input Capacitance
0 < VI < VCC
V
0.7VCC
V
+ 10
20
µA
pF
0.4
V
1.45
– 10
V
OUTPUT BUFFER (SO pin)
VSOL
Output LOW Voltage
Output HIGH Voltage
IO = 1.6mA
IO = 0.8mA
ISOtl
Output Tristate Leakage
Current
0 < VO < VCC, CE Pin Held High,
VCC = 5.25V
CSO
Output Capacitance
ICC
Quiescent Supply
Current at VCC Pin
VSOH
VCC
– 1.3V
V
10
µA
0 < VO < VCC
CE Pin Held High
20
pF
All Outputs Progr. ON. IO = 0.5A
per Output Simultaneously
10
mA
2
MHz
– 10
SERIAL PERIPHERAL INTERFACE (see fig. 2, timing diagram)
4/9
fop
tlead
Operating Frequency
D.C.
Enable Lead Time
250
ns
tlag
Enable Lag Time
250
ns
twSCKH
twSCKL
tsu
tH
tEN
tDIS
tV
Clock HIGH Time
Clock LOW Time
Data Setup Time
Data Hold Time
Enable Time
Disable Time
Data Valid Time
200
200
75
75
250
250
100
ns
ns
ns
ns
ns
ns
ns
trSO
tfSO
trSI
Rise Time (SO output)
Fall Time (SO output)
Rise Time SPI
Inputs (SCK, SI, CE)
VCC = 20 to 70% CL = 200pF
VCC = 70 to 20% CL = 200pF
VCC = 20 to 70% CL = 200pF
50
50
200
ns
ns
ns
tfSI
Fall Time SPI
Inputs (SCLK, SI, CE)
VCC = 70 to 20% CL = 200pF
200
ns
tho
Output Data Hold Time
0
ns
L9822N
FUNCTIONAL DESCRIPTION
The L9822N DMOS output is a low operating power
device featu-ring, eight 1Ω RDSON DMOS drivers
with transient protection circuits in output stages.
Each channel is independently controlled by an output latch and a common RESET line which disables
all eight outputs. The driver has low saturation and
short circuit protection and can drive inductive and resistive loads such as solenoids, lamps and relais.
Data is transmitted to the device serially using the
Serial Peripheral Interface (SPI) protocol. The circuit
receives 8 bit serial data by means of the serial input
(SI) which is stored in an internal register to control
the output drivers. The serial output (SO) provides 8
bit of diagnostic data representing the voltage level
at the driver output. This allows the microprocessor
to diagnose the condition of the output drivers.
The output saturation voltage is monitored by a
comparator for an out of saturation condition and is
able to unlatch the particular driver through the fault
reset line. This circuit is also cascadable with another octal driver in order to jam 8 bit multiple data.
The device is selected when the chip enable (CE)
line is low.
Additionally the (SO) is placed in a tri-state mode
when the device is deselected. The negative edge
of the (CE) transfers the voltage level of the drivers
to the shift register and the positive edge of the (CE)
latches the new data from the shift register to the
drivers. When CE is Low, data bit contained into the
shift register is transferred to SO output at every
SCLK positive transition while data bit present at SI
input is latched into the shift register on every SCLK
negative transition.
Internal Blocks Description
The internal architecture of the device is based on
the three internal major blocks : the octal shift register for talking to the SPI bus, the octal latch for holding control bits written into the device and the octal
load driver array.
Shift Register
The shift register has both serial and parallel inputs
and serial and parallel outputs. The serial input accepts data from the SPI bus and the serial output
simultaneously sends data into the SPI bus. The
parallel outputs are latched into the parallel latch inside the L9822N at the end of a data transfer. The
parallel inputs jam diagnostic data into the shift register at the beginning of a data transfer cycle.
Parallel Latch
The parallel latch holds the input data from the shift
register. This data then actuates the output stages.
Individual registers in the latch may be cleared by
fault conditions in order to protect the overloaded
output stages. The entire latch may also be cleared
by the RESET signal.
Output Stages
The output stages provide an active low drive signal
suitable for 0.75A continuous loads. The outputs
have internal zeners set to 36 volts to clamp inductive transients at turn-off. Each output also has a
voltage comparator observing the output node. If the
voltage exceeds 1.8V on an ON output pin, a fault
condition is assumed and the latch driving this particular stage is reset, turning the output OFF to protect it. The timing of this action is described below.
These comparators also provide diagnostic feedback data to the shift register. Additionally, the comparators contain an internal pulldown current which
will cause the cell to indicate a low output voltage if
the output is programmed OFF and the output pin
is open circuited.
TIMING DATA TRANSFER
Figure #2 shows the overall timing diagram from a
byte transfer to and from the L9822NSP using the
SPI bus.
CE High to Low Transition
The action begins when the Chip Enable (CE) pin is
pulled low. The tri-state Serial Output (SO) pin driver
will be enabled entire time that CE is low. At the falling edge of the CE pin, the diagnostic data from the
voltage comparators in the output stages will be
latched into the shift register. If a particular output is
high, a logic one will be jammed into that bit in the
shift register. If the output is low, a logic zero will be
loaded there. The most significant bit (07) should be
presented at the Serial Input (SI) pin. A zero at this
pin will program an output ON, while a one will program the output OFF.
SCLK Transitions
The Serial Clock (SCLK) pin should then be pulled
high. At this point the diagnostic bit from the most
significant output (07) will appear at the SO pin. A
high here indicates that the 07 pin is higher than
1.8V. The SCLK pin should then be toggled low then
high. New SO data will appear following every rising
edge of SCLK and new SI data will be latched into
the L9822N shift register on the falling edges. An unlimited amount of data may be shifted through the
device shift register (into the SI pin and out the SO
pin), allowing the other SPI devices to be cascaded
in a daisy chain with the L9822N.
5/9
L9822N
CE Low to High Transition
Once the last data bit has been shifted into the
L9822NSP, the CE pin should be pulled high.
At the rising edge of CE the shift register data is
latched into the parallel latch and the output stages
will be actuated by the new data. An internal 160µs
delay timer will also be started at this rising edge
(see tUD). During the 160µs period, the outputs will
be protected only by the analog current limiting circuits since the resetting of the parallel latches by
faults conditions will be inhibited during this period.
This allows the part to overcome any high inrush currents that may flow immediately after turn on. Once
the delay period has elapsed, the output voltages
are sensed by the comparators and any output with
voltages higher than 1.8V are latched OFF. It should
be noted that the SCLK pin should be low at both
transitions of the CE pin to avoid any false clocking
of the shift register. The SCLK input is gated by the
Figure 1 : Byte Timing with Asynchronous Reset.
6/9
CE pin, so that the SCLK pin is ignored whenever
the CE pin is high.
FAULT CONDITIONS CHECK
Checking for fault conditions may be done in the following way. Clock in a new control byte. Wait 160
microseconds or so to allow the outputs to settle.
Clock in the same control byte and observe the diagnostic data that comes out of the device. The diagnostic bits should be identical to the bits that were
first clocked in. Any differences would point to a fault
on that output. If the output was programmed ON by
clocking in a zero, and a one came back as the diagnostic bit for that output, the output pin was still
high and a short circuit or overload condition exists.
If the output was programmed OFF by clocking in a
one, and a zero came back as the diagnostic bit for
that output, nothing had pulled the output pin high
and it must be floating, so an open circuit condition
exists for that output.
L9822N
Figure 2 : Timing Diagram.
Figure 3 : Typical Application Circuit.
N
7/9
L9822N
mm
inch
DIM.
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
2.35
2.65
0.093
0.104
A1
0.10
0.30
0.004
0.012
B
0.33
0.51
0.013
0.200
C
0.23
0.32
0.009
0.013
D (1)
12.60
13.00
0.496
0.512
E
7.40
7.60
0.291
0.299
e
1.27
0.050
H
10.0
10.65
0.394
0.419
h
0.25
0.75
0.010
0.030
L
0.40
1.27
0.016
0.050
k
ddd
OUTLINE AND
MECHANICAL DATA
0˚ (min.), 8˚ (max.)
0.10
0.004
(1) “D” dimension does not include mold flash, protusions or gate
burrs. Mold flash, protusions or gate burrs shall not exceed
0.15mm per side.
SO20
0016022 D
8/9
L9822N
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No
license is granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specifications mentioned in this
publication are subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products are not authorized for use as critical components in life support devices or systems without express written
approval of STMicroelectronics.
The ST logo is a registered trademark of STMicroelectronics.
All other names are the property of their respective owners
© 2003 STMicroelectronics - All rights reserved
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