ETC X51638V14-1.8

X51638
CPU Supervisor with 16Kb SPI EEPROM
FEATURES
DESCRIPTION
• Extended Power-On Reset (800ms Nominal)
• Selectable Watchdog Timer
• Low Vcc Detection and Reset Assertion
—Five Standard Reset Threshold Voltages
—Re-program Low Vcc Reset Threshold Voltage
using special programming sequence
—Reset Signal Valid to Vcc=1V
• Determine Watchdog or Low Voltage Reset with
a Volatile Flag bit
• Long Battery Life With Low Power Consumption
—<50mA Max Standby Current, Watchdog On
—<1mA Max Standby Current, Watchdog Off
—<400mA Max Active Current during Read
• 16Kbits of EEPROM
• Built-in Inadvertent Write Protection
—Power-Up/Power-Down Protection Circuitry
—Protect 0, 1/4, 1/2 or all of EEPROM Array with
Block LockTM Protection
—In Circuit Programmable ROM Mode
• 2MHz SPI Interface Modes (0,0 & 1,1)
• Minimize EEPROM Programming Time
—32 Byte Page Write Mode
—Self-Timed Write Cycle
—5ms Write Cycle Time (Typical)
• 1.8V to 3.6V, 2.7V to 5.5V and 4.5V to 5.5V Power
Supply Operation
• Available Packages
—14-Lead TSSOP, 8-Lead SOIC
This device combines four popular functions, Power-on
Reset Control, Watchdog Timer, Supply Voltage Supervision, and Block Lock™ Protect Serial EEPROM in one
package. This combination lowers system cost, reduces
board space requirements, and increases reliability.
Applying power to the device activates a power on reset
circuit which holds RESET active for a period of time.
This allows the power supply and oscillator to stabilize
before the processor can execute code. This device
allows 800ms before releasing the controller.
The Watchdog Timer provides an independent protection
mechanism for microcontrollers. When the microcontroller fails to restart a timer within a selectable time-out
interval, the device activates the RESET signal. The user
selects the interval from three preset values. Once
selected, the interval does not change, even after cycling
the power.
The X51638 low Vcc detection circuitry protects the
user’s system from low voltage conditions, resetting the
system when Vcc falls below the minimum Vcc trip point.
RESET is asserted until Vcc returns to proper operating
level and stabilizes. Five industry standard VTRIP thresholds are available, however, Xicor’s unique circuits allow
the thresold to be reprogrammed to meet custom
requirements or to fine-tune the threshold for applications
requiring higher precision.
BLOCK DIAGRAM
WATCHDOG TRANSITION
DETECTOR
WP
WATCHDOG
TIMER RESET
PROTECT LOGIC
RESET
SI
DATA
SO
REGISTER
STATUS
REGISTER
DECODE &
4K BITS
CONTROL
CS/WDI
LOGIC
4K BITS
VCC THRESHOLD
8K BITS
RESET LOGIC
VCC
EEPROM ARRAY
COMMAND
SCK
RESET &
WATCHDOG
TIMEBASE
POWER ON AND
LOW VOLTAGE
RESET
+
GENERATION
VTRIP
ÓXicor, Inc. 1999 Patents Pending
9900-3002.10 2/12/99 T0/C0/D0
-
1
Characteristics subject to change without notice
X51638
PIN DESCRIPTION
PIN
(SOIC/PDIP)
PIN
TSSOP
Name
Function
1
1
CS/WDI
Chip Select Input. CS HIGH, deselects the device and the SO output pin
is at a high impedance state. Unless a nonvolatile write cycle is underway,
the device will be in the standby power mode. CS LOW enables the device,
placing it in the active power mode. Prior to the start of any operation after
power up, a HIGH to LOW transition on CS is required
Watchdog Input. A HIGH to LOW transition on the WDI pin restarts the
Watchdog timer. The absence of a HIGH to LOW transition within the
watchdog time-out period results in RESET going active.
2
2
SO
Serial Output. SO is a push/pull serial data output pin. A read cycle shifts data
out on this pin. The falling edge of the serial clock (SCK) clocks the data out.
5
8
SI
Serial Input. SI is a serial data input pin. Input all opcodes, byte addresses,
and memory data on this pin. The rising edge of the serial clock (SCK) latches
the input data. Send all opcodes (Table 1), addresses and data MSB first.
6
9
SCK
Serial Clock. The Serial Clock controls the serial bus timing for data input and
output. The rising edge of SCK latches in the opcode, address, or data bits
present on the SI pin. The falling edge of SCK changes the data output on the
SO pin.
3
6
WP
Write Protect. The WP pin works in conjunction with a nonvolatile WPEN
bit to “lock” the setting of the Watchdog Timer control and the memory write
protect bits.
4
7
VSS
Ground
8
14
VCC
Supply Voltage
7
13
RESET
3-5,10-12
NC
Reset Output. RESET is an active LOW open drain output which goes
active whenever Vcc falls below the minimum Vcc sense level. It will
remain active until Vcc rises above the minimum Vcc sense level for
800ms. RESET goes active if the Watchdog Timer is enabled and CS
remains either HIGH or LOW longer than the selectable Watchdog time-out
period. A falling edge of CS will reset the Watchdog Timer. RESET goes
active on power up at 1V and remains active for 800ms after the power
supply stabilizes.
No internal connections
PIN CONFIGURATION
14-LEAD TSSOP
8-LEAD SOIC/PDIP
CS
1
X51638
8
V CC
SO
2
7
RESET
WP
3
6
SCK
4
5
SI
VSS
2
CS
1
X51638
14
V CC
SO
2
13
RESET
NC
3
12
NC
NC
4
11
NC
NC
5
10
NC
WP
VSS
6
9
SCK
7
8
SI
X51638
PRINCIPLES OF OPERATION
To set the new VTRIP voltage, apply the desired VTRIP
threshold to the Vcc pin and tie the CS/WDI pin and the
WP pin HIGH. RESET and SO pins are left unconnected.
Then apply the programming voltage Vp to both SCK and
SI and pulse CS/WDI LOW then HIGH. Remove Vp and
the sequence is complete.
POWER ON RESET
Application of power to the X51638 activates a Power On
Reset Circuit. This circuit goes active at VCC sense level
(VTRIP) and pulls the RESET pin LOW. This signal prevents the system microprocessor from starting to operate
with insufficient voltage or prior to stabilization of the oscillator. When Vcc exceeds the device VTRIP value for
800ms (nominal) the circuit releases RESET, allowing the
processor to begin executing code.
Figure 1. Set VTRIP Voltage
CS
Vp
LOW VOLTAGE MONITORING
SCK
During operation, the X51638 monitors the VCC level and
asserts RESET if supply voltage falls below a preset minimum VTRIP. The RESET signal prevents the microprocessor from operating in a power fail or brownout condition.
The RESET signal remains active until the voltage drops
below 1V. It also remains active until Vcc returns and
exceeds VTRIP for 800ms.
Vp
SI
Resetting the VTRIP Voltage
This procedure sets the VTRIP to a “native” voltage level.
For example, if the current VTRIP is 4.4V and the VTRIP is
reset, the new VTRIP is something less than 1.7V. This
procedure must be used to set the voltage to a lower
value.
WATCHDOG TIMER
The Watchdog Timer circuit monitors the microprocessor
activity by monitoring the WDI input. The microprocessor
must toggle the CS/WDI pin periodically to prevent a
RESET signal. The CS/WDI pin must be toggled from
HIGH to LOW prior to the expiration of the watchdog timeout period. The state of two nonvolatile control bits in the
Status Register determine the watchdog timer period. The
microprocessor can change these watchdog bits, or they
may be “locked” by tying the WP pin LOW and setting the
WPEN bit HIGH.
To reset the VTRIP voltage, apply a voltage between 2.7
and 5.5V to the Vcc pin. Tie the CS/WDI pin, the WP pin,
AND THE SCK pin HIGH. RESET and SO pins are left
unconnected. Then apply the programming voltage Vp to
the SI pin ONLY and pulse CS/WDI LOW then HIGH.
Remove Vp and the sequence is complete.
Figure 2. Reset VTRIP Voltage
VCC THRESHOLD RESET PROCEDURE
The X51638 is offered with one of several standard Vcc
threshold (VTRIP) voltages. This value will not change
over normal operating and storage conditions. However,
in applications where the standard VTRIP is not exactly
right, or for higher precision in the VTRIP value, the
X51638 threshold may be adjusted.
CS
SCK
Vcc
Vp
SI
Setting the VTRIP Voltage
This procedure sets the VTRIP to a higher voltage value.
For example, if the current VTRIP is 4.4V and the new
VTRIP is 4.6V, this procedure directly makes the change. If
the new setting is lower than the current setting, then it is
necessary to reset the trip point before setting the new
value.
3
X51638
Figure 3. VTRIP Programming Sequence Flow Chart
VTRIP Programming
Execute
Reset VTRIP
Sequence
Set Vcc = Vcc applied =
Desired VTRIP
New Vcc applied =
Old Vcc applied + Error
Execute
Set VTRIP
Sequence
New Vcc applied =
Old Vcc applied - Error
Apply 5V to Vcc
Execute
Reset VTRIP
Sequence
Decrement Vcc
(Vcc = Vcc - 50mV)
NO
RESET pin
goes active?
YES
Error < 0
Measured VTRIP Desired VTRIP
Error > 0
Error = 0
DONE
Figure 4. Sample VTRIP Reset Circuit
VP
NC
4.7K
1
NC
VTRIP
+
Adj.
X51638
RESET
8
2
7
3
6
4
5
4.7K
NC
Program
10K
4
10K
Reset VTRIP
Test VTRIP
Set VTRIP
X51638
SPI SERIAL MEMORY
Write Enable Latch
The device contains a Write Enable Latch. This latch
must be SET before a Write Operation is initiated. The
WREN instruction will set the latch and the WRDI instruction will reset the latch (Figure 3). This latch is automatically reset upon a power-up condition and after the
completion of a valid Write Cycle.
The memory portion of the device is a CMOS Serial
EEPROM array with Xicor’s Block LockTM Protection. The
array is internally organized as x 8. The device features a
Serial Peripheral Interface (SPI) and software protocol
allowing operation on a simple four-wire bus.
The device utilizes Xicor’s proprietary Direct WriteTM cell,
providing a minimum endurance of 100,000 cycles and a
minimum data retention of 100 years.
Status Register
The RDSR instruction provides access to the Status Register. The Status Register may be read at any time, even
during a Write Cycle. The Status Register is formatted as
follows:
The device is designed to interface directly with the synchronous Serial Peripheral Interface (SPI) of many popular microcontroller families. It contains an 8-bit instruction
register that is accessed via the SI input, with data being
clocked in on the rising edge of SCK. CS must be LOW
during the entire operation.
7
6
WPEN FLB
All instructions (Table 1), addresses and data are transferred MSB first. Data input on the SI line is latched on the
first rising edge of SCK after CS goes LOW. Data is output on the SO line by the falling edge of SCK. SCK is
static, allowing the user to stop the clock and then start it
again to resume operations where left off.
5
4
WD1 WD0
3
2
1
0
BL1
BL0
WEL
WIP
The Write-In-Progress (WIP) bit is a volatile, read only bit
and indicates whether the device is busy with an internal
nonvolatile write operation. The WIP bit is read using the
RDSR instruction. When set to a “1”, a nonvolatile write
operation is in progress. When set to a “0”, no write is in
progress.
Table 1. Instruction Set
Instruction Name
Instruction Format*
Operation
WREN
0000 0110
Set the Write Enable Latch (Enable Write Operations)
SFLB
0000 0000
Set Flag Bit
WRDI/RFLB
0000 0100
Reset the Write Enable Latch/Reset Flag Bit
RSDR
0000 0101
Read Status Register
WRSR
0000 0001
Write Status Register(Watchdog,BlockLock,WPEN & Flag Bits)
READ
0000 0011
Read Data from Memory Array Beginning at Selected Address
WRITE
0000 0010
Write Data to Memory Array Beginning at Selected Address
*Instructions are shown MSB in leftmost position. Instructions are transferred MSB first.
Table 2. Block Protect Matrix
WREN CMD
STATUS
REGISTER
DEVICE
PIN
BLOCK
BLOCK
STATUS
REGISTER
UNPROTECTED
BLOCK
WPEN, BL0, BL1
WD0, WD1
WEL
WPEN
WP#
PROTECTED
BLOCK
0
X
X
Protected
Protected
Protected
1
1
0
Protected
Writable
Protected
1
0
X
Protected
Writable
Writable
1
X
1
Protected
Writable
Writable
5
X51638
The Write Enable Latch (WEL) bit indicates the Status of
the Write Enable Latch. When WEL=1, the latch is set
HIGH and when WEL=0 the latch is reset LOW. The WEL
bit is a volatile, read only bit. It can be set by the WREN
instruction and can be reset by the WRDS instruction.
Status Register Bits
The Block Lock bits, BL0 and BL1, set the level of Block
LockTM Protection. These nonvolatile bits are programmed using the WRSR instruction and allow the user
to protect one quarter, one half, all or none of the
EEPROM array. Any portion of the array that is Block Lock
Protected can be read but not written. It will remain protected until the BL bits are altered to disable Block Lock
Protection of that portion of memory.
Status
Register Bits
BL0
X516x
0
0
None
0
1
$0600–$07FF
1
0
$0400–$07FF
1
1
$0000–$07FF
WD0
0
0
1.4 Seconds
0
1
600 Milliseconds
1
0
400 Milliseconds
1
1
Disabled
The FLAG bit shows the status of a volatile latch that can
be set and reset by the system using the SFLB and RFLB
instructions. The Flag bit is automatically reset upon
power up. This flag can be used by the system to determine whether a reset occurs as a result of a watchdog
time-out or power failure.
Array Addresses Protected
BL1
Watchdog Time-out
(Typical)
WD1
The nonvolatile WPEN bit is programmed using the
WRSR instruction. This bit works in conjunction with the
WP pin to provide an In-Circuit Programmable ROM function (Table 2). WP is LOW and WPEN bit programmed
HIGH disables all Status Register Write Operations.
In Circuit Programmable ROM Mode
This mechanism protects the Block Lock and Watchdog
bits from inadvertant corruption.
The Watchdog Timer bits, WD0 and WD1, select the
Watchdog Time-out Period. These nonvolatile bits are
programmed with the WRSR instruction.
In the locked state (Programmable ROM Mode) the WP
pin is LOW and the nonvolatile bit WPEN is “1”. This mode
disables nonvolatile writes to the device’s Status Register.
Figure 5. Read EEPROM Array Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
20 21 22 23 24 25
26 27 28 29 30
SCK
INSTRUCTION
16 BIT ADDRESS
15 14 13
SI
3
2
1
0
DATA OUT
HIGH IMPEDANCE
7
SO
MSB
6
6
5
4
3
2
1
0
X51638
Setting the WP pin LOW while WPEN is a “1” while an
internal write cycle to the Status Register is in progress
will not stop this write operation, but the operation disables subsequent write attempts to the Status Register.
must then be taken HIGH. If the user continues the Write
Operation without taking CS HIGH after issuing the
WREN instruction, the Write Operation will be ignored.
To write data to the EEPROM memory array, the user
then issues the WRITE instruction followed by the 16 bit
address and then the data to be written. Any unused
address bits are specified to be “0’s”. The WRITE operation minimally takes 32 clocks. CS must go low and
remain low for the duration of the operation. If the
address counter reaches the end of a page and the clock
continues, the counter will roll back to the first address of
the page and overwrite any data that may have been previously written.
When WP is HIGH, all functions, including nonvolatile
writes to the Status Register operate normally.
Setting the WPEN bit in the Status Register to “0” blocks
the WP pin function, allowing writes to the Status Register when WP is HIGH or LOW. Setting the WPEN bit to
“1” while the WP pin is LOW activates the Programmable
ROM mode, thus requiring a change in the WP pin prior
to subsequent Status Register changes. This allows
manufacturing to install the device in a system with WP
pin grounded and still be able to program the Status Register. Manufacturing can then load Configuration data,
manufacturing time and other parameters into the
EEPROM, then set the portion of memory to be protected by setting the Block Lock bits, and finally set the
“OTP mode” by setting the WPEN bit. Data changes now
require a hardware change.
For the Page Write Operation (byte or page write) to be
completed, CS can only be brought HIGH after bit 0 of
the last data byte to be written is clocked in. If it is brought
HIGH at any other time, the write operation will not be
completed (Figure 4).
To write to the Status Register, the WRSR instruction is
followed by the data to be written (Figure 5). Data bits 0
and 1 must be “0” .
Read Sequence
When reading from the EEPROM memory array, CS is
first pulled low to select the device. The 8-bit READ
instruction is transmitted to the device, followed by the
16-bit address. After the READ opcode and address are
sent, the data stored in the memory at the selected
address is shifted out on the SO line. The data stored in
memory at the next address can be read sequentially by
continuing to provide clock pulses. The address is automatically incremented to the next higher address after
each byte of data is shifted out. When the highest
address is reached, the address counter rolls over to
address $0000 allowing the read cycle to be continued
indefinitely. The read operation is terminated by taking
CS high. Refer to the Read EEPROM Array Sequence
(Figure 1).
While the write is in progress following a Status Register
or EEPROM Sequence, the Status Register may be read
to check the WIP bit. During this time the WIP bit will be
high.
OPERATIONAL NOTES
The device powers-up in the following state:
• The device is in the low power standby state.
• A HIGH to LOW transition on CS is required to enter
an active state and receive an instruction.
• SO pin is high impedance.
• The Write Enable Latch is reset.
• The Flag Bit is reset.
• Reset Signal is active for tPURST.
To read the Status Register, the CS line is first pulled low
to select the device followed by the 8-bit RDSR instruction. After the RDSR opcode is sent, the contents of the
Status Register are shifted out on the SO line. Refer to
the Read Status Register Sequence (Figure 2).
Data Protection
The following circuitry has been included to prevent inadvertent writes:
• A WREN instruction must be issued to set the Write
Enable Latch.
• CS must come HIGH at the proper clock count in order
to start a nonvolatile write cycle.
Write Sequence
Prior to any attempt to write data into the device, the
“Write Enable” Latch (WEL) must first be set by issuing
the WREN instruction (Figure 3). CS is first taken LOW,
then the WREN instruction is clocked into the device.
After all eight bits of the instruction are transmitted, CS
7
X51638
Figure 6. Read Status Register Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
7
6
5
11 12 13 14
SCK
INSTRUCTION
SI
DATA OUT
SO
HIGH IMPEDANCE
MSB
Figure 7. Write Enable Latch Sequence
CS
0
1
2
3
4
SCK
SI
SO
HIGH IMPEDANCE
8
5
6
7
4
3
2
1
0
X51638
Figure 8. Write Sequence
CS
0
1
2
3
4
5
6
7
8
9
15
14
10
20
21
22
23
24
25
26
1
0
7
6
5
27
28
29
30
31
1
0
SCK
INSTRUCTION
16 BIT ADDRESS
SI
13
3
DATA BYTE 1
2
4
3
2
CS
32
33
34
7
6
5
35
36
37
38
39
40
41
42
1
0
7
6
5
43
44
45
46
47
1
0
SCK
DATA BYTE 2
SI
4
3
DAT A BYTE 3
2
4
3
2
DATA BYTE N
6
5
4
3
13
14
15
1
0
2
1
0
Figure 9. Status Register Write Sequence
CS
0
1
2
3
4
5
6
7
8
9
10
7
6
5
11
12
SCK
DATA BYTE
INSTRUCTION
SI
SO
4
3
2
HIGH IMPEDANCE
Symbol Table
WAVEFORM
9
INPUTS
OUTPUTS
Must be
steady
Will be
steady
May change
from LOW
to HIGH
Will change
from LOW
to HIGH
May change
from HIGH
to LOW
Will change
from HIGH
to LOW
Don’t Care:
Changes
Allowed
N/A
Changing:
State Not
Known
Center Line
is High
Impedance
X51638
ABSOLUTE MAXIMUM RATINGS*
*COMMENT
Temperature under Bias ........................–65°C to +135°C
Storage Temperature .............................–65°C to +150°C
Voltage on any Pin with Respect to VSS....... –1.0V to +7V
D.C. Output Current ....................................................5mA
Lead Temperature (Soldering, 10 seconds)............ 300°C
Stresses above those listed under “Absolute Maximum
Ratings” may cause permanent damage to the device.
This is a stress rating only and the functional operation of
the device at these or any other conditions above those
listed in the operational sections of this specification is not
implied. Exposure to absolute maximum rating conditions
for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
Temp
Min.
Max.
Commercial
0°C
70°C
–1.8
Industrial
–40°C
+85°C
–2.7 or -2.7A
Voltage Option
Supply Voltage
1.8V-3.6V
2.7V to 5.5V
4.5V-5.5V
Blank or -4.5A
D.C. OPERATING CHARACTERISTICS (Over the recommended operating conditions unless otherwise specified.)
Limits
Symbol
Parameter
Min.
Typ.
Max.
Units
Test Conditions
ICC1
VCC Write Current (Active)
5
mA
SCK = VCC x 0.1/VCC x 0.9 @ 2MHz,
SO = Open
ICC2
VCC Read Current (Active)
0.4
mA
SCK = VCC x 0.1/VCC x 0.9 @ 2MHz,
SO = Open
ISB1
VCC Standby Current
WDT=OFF
1
µA
ISB2
VCC Standby Current
WDT=ON
50
µA
ISB3
VCC Standby Current
WDT=ON
20
µA
ILI
Input Leakage Current
0.1
10
µA
VIN = VSS to VCC
ILO
Output Leakage Current
0.1
10
µA
VOUT = VSS to VCC
VIL(1)
Input LOW Voltage
–0.5
VCCx0.3
V
VIH(1)
Input HIGH Voltage
VCCx0.7
VCC+0.5
V
VOL1
Output LOW Voltage
0.4
V
VCC > 3.3V, IOL = 2.1mA
VOL2
Output LOW Voltage
0.4
V
2V < VCC £ 3.3V, IOL = 1mA
VOL3
Output LOW Voltage
0.4
V
VCC £ 2V, IOL = 0.5mA
VOH1
Output HIGH Voltage
VCC–0.8
V
VCC > 3.3V, IOH = –1.0mA
VOH2
Output HIGH Voltage
VCC–0.4
V
2V < VCC £ 3.3V, IOH = –0.4mA
VOH3
Output HIGH Voltage
VCC–0.2
V
VCC £ 2V, IOH = –0.25mA
VOLS
Reset Output LOW Voltage
V
IOL = 1mA
0.4
10
CS = VCC, VIN = VSS or VCC,
VCC = 5.5V
CS = VCC, VIN = VSS or VCC,
VCC = 5.5V
CS = VCC, VIN = VSS or VCC,
VCC =3.6V
X51638
CAPACITANCE TA = +25°C, f = 1MHz, VCC = 5V.
Symbol
Test
(2)
Output Capacitance (SO, RESET)
COUT
(2)
Input Capacitance (SCK, SI, CS, WP)
CIN
Notes:
Max.
Units
Conditions
8
pF
VOUT = 0V
6
pF
VIN = 0V
(1) VIL min. and VIH max. are for reference only and are not tested.
(2) This parameter is periodically sampled and not 100% tested.
EQUIVALENT A.C. LOAD CIRCUIT AT 5V VCC
5V
A.C. TEST CONDITIONS
Input Pulse Levels
5V
Input Rise and Fall Times
3.3KW
1.64KW
SO
OUTPUT
1.64KW
Input and Output Timing Level
RESET
100pF
30pF
11
VCC x 0.1 to VCC x 0.9
10ns
VCC x 0.5
X51638
A.C. CHARACTERISTICS (Over recommended operating conditions, unless otherwise specified)
Serial Input Timing
1.8-3.6V
Symbol
Parameter
2.7-5.5V
Min.
Max.
Min.
Max.
Units
0
1
0
2
MHz
fSCK
Clock Frequency
tCYC
Cycle Time
1000
500
ns
tLEAD
CS Lead Time
500
250
ns
tLAG
CS Lag Time
500
250
ns
tWH
Clock HIGH Time
400
200
ns
tWL
Clock LOW Time
400
250
ns
tSU
Data Setup Time
50
50
ns
tH
Data Hold Time
50
50
ns
tRI(3)
Input Rise Time
100
100
ns
tFI(3)
Input Fall Time
100
100
ns
tCS
CS Deselect Time
tWC
(4)
500
500
Write Cycle Time
ns
10
10
ms
Serial Input Timing
tCS
CS
tLEAD
tLAG
SCK
tSU
SI
tH
tRI
MSB IN
t FI
LSB IN
HIGH IMPEDANCE
SO
12
X51638
Serial Output Timing
1.8-3.6V
Symbol
Parameter
2.7-5.5V
Min.
Max.
Min.
Max.
Units
0
1
0
2
MHz
fSCK
Clock Frequency
tDIS
Output Disable Time
250
250
ns
tV
Output Valid from Clock Low
400
250
ns
tHO
Output Hold Time
tRO(3)
Output Rise Time
100
100
ns
tFO(3)
Output Fall Time
100
100
ns
Notes:
0
0
ns
(3) This parameter is periodically sampled and not 100% tested.
(4) tWC is the time from the rising edge of CS after a valid write sequence has been sent to the end of the self-timed internal
nonvolatile write cycle.
Serial Output Timing
CS
t CYC
tWH
t LAG
SCK
tV
SO
SI
MSB OUT
tHO
MSB–1 OUT
t WL
tDIS
LSB OUT
ADDR
LSB IN
13
X51638
Power-Up and Power-Down Timing
VTRIP
V TRIP
VCC
t PURST
0 Volts
t PURST
t
F
t RPD
tR
RESET
RESET Output Timing
Symbol
Parameter
Min.
Typ.
Max.
Units
4.5
4.25
2.85
2.55
1.7
4.62
4.38
2.92
2.62
1.75
4.75
4.5
3.0
2.7
1.8
V
VTRIP
Reset Trip Point Voltage, X51638-4.5A
Reset Trip Point Voltage, X51638
Reset Trip Point Voltage, X51638-2.7A
Reset Trip Point Voltage, X51638-2.7
Reset Trip Point Voltage, X51638-1.8
VTH(5)
VTRIP Hysteresis
(HIGH to LOW vs. LOW to HIGH VTRIP voltage)
tPURST
Power-up Reset Timeout
tRPD(5)
VCC Detect to Reset/Output
tF(5)
VCC Fall Time
100
ms
tR(5)
VCC Rise Time
100
ms
VRVALID
Reset Valid VCC
1
V
Notes:
20
500
(5) This parameter is periodically sampled and not 100% tested.
14
800
mV
1400
ms
500
ns
X51638
CS/WDI vs. RESET Timing
CS/WDI
t CST
RESET
t WDO
t WDO
t RST
t RST
RESET Output Timing (WD1 = 1, WD0 = 0)
Symbol
Parameter
Min.
Typ.
Max.
Units
tWDO
Watchdog Timeout Period
300
400
550
ms
tCST
CS Pulse Width to Reset the Watchdog
400
tRST
Reset Timeout
200
400
600
ms
Parameter
Min.
Typ.
Max.
Units
tWDO
Watchdog Timeout Period
450
600
800
ms
tCST
CS Pulse Width to Reset the Watchdog
400
tRST
Reset Timeout
100
200
300
ms
Min.
Typ.
Max.
Units
1
1.4
2
sec
ns
RESET Output Timing (WD1 = 0, WD0 = 1)
Symbol
ns
RESET Output Timing (WD1 = 0, WD0 = 0)
Symbol
Parameter
tWDO
Watchdog Timeout Period
tCST
CS Pulse Width to Reset the Watchdog
400
tRST
Reset Timeout
100
15
ns
200
300
ms
X51638
VTRIP Set Conditions
tTHD
Vcc
VTrip
tTSU
tRP
tP
tVPS
CS
tVPH
tVPH
tVPS
tVPO
Vp
SCK
Vp
tVPO
SI
VTRIP Reset Conditions
tTHD
Vcc
VTrip
tTSU
tVPS
CS
SCK
tRP
tP
tVPS
tVP1
tVPH
tVPO
Vcc
Vp
tVPO
SI
16
X51638
Table 3. VTRIP Programming Specifications: Vcc=1.7-5.5V; Temperature = 0oC to 70oC
Parameter
Description
Min
Max
Units
tVPS
SCK VTRIP Program Voltage Setup time
1
ms
tVPH
SCK VTRIP Program Voltage Hold time
1
ms
tP
VTRIP Program Pulse Width
1
ms
tTSU
VTRIP Level Setup time
10
ms
tTHD
VTRIP Level Hold (stable) time
10
ms
tWC
VTRIP Write Cycle Time
tRP
VTRIP Program Cycle Recovery Period
(Between successive programming cycles)
10
ms
tVPO
SCK VTRIP Program Voltage Off time before next cycle
0
ms
Vp
Programming Voltage
15
18
V
VTRIP
VTRIP Programed Voltage
1.7
5.0
V
Vta
VTRIP Programed Voltage accuracy (Vcc applied - VTRIP)
-0.3
+0.3
V
Vtr
VTRIP Programed Voltage repeatability
(Successive program operations.)
-5
+5
mV
10
VTRIP Programming parameters are periodically sampled and are not 100% Tested.
17
ms
X51638
8-LEAD PLASTIC SMALL OUTLINE GULL WING PACKAGE TYPE S
0.150 (3.80)
0.158 (4.00)
0.228 (5.80)
0.244 (6.20)
PIN 1 INDEX
PIN 1
0.014 (0.35)
0.019 (0.49)
0.188 (4.78)
0.197 (5.00)
(4X) 7°
0.053 (1.35)
0.069 (1.75)
0.004 (0.19)
0.010 (0.25)
0.050 (1.27)
0.010 (0.25)
0.020 (0.50) X 45°
0.050" TYPICAL
0.050"
TYPICAL
0° – 8°
0.0075 (0.19)
0.010 (0.25)
0.250"
0.016 (0.410)
0.037 (0.937)
FOOTPRINT
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
18
0.030"
TYPICAL
8 PLACES
X51638
14-LEAD PLASTIC, TSSOP, PACKAGE TYPE V
.025 (.65) BSC
.169 (4.3)
.252 (6.4) BSC
.177 (4.5)
.193 (4.9)
.200 (5.1)
.047 (1.20)
.0075 (.19)
.0118 (.30)
.002 (.05)
.006 (.15)
.010 (.25)
Gage Plane
0° – 8°
Seating Plane
.019 (.50)
.029 (.75)
Detail A (20X)
.031 (.80)
.041 (1.05)
See Detail “A”
NOTE: ALL DIMENSIONS IN INCHES (IN PARENTHESES IN MILLIMETERS)
19
X51638
Ordering Information
Vcc Range
4.5-5.5V
VTRIP Range
4.5-4.75
Package
Operating
Temperature Range
PART NUMBER
RESET (Active LOW)
8 pin PDIP
0oC - 70oC
X51638P-4.5A
o
8L SOIC
8 pin PDIP
4.5-5.5V
4.25-4.5
8L SOIC
2.7-5.5V
1.8-3.6V
2.85-3.0
2.55-2.7
1.7-1.8V
0 C - 70 C
X51638S8-4.5A
-40oC - 85oC
X51638S8I-4.5A
0oC - 70oC
X51638P
0oC - 70oC
X51638S8
-40oC
14L TSSOP
2.7-5.5V
o
-
85oC
0°c - 70°C
oC
0
8L SOIC
-
70oC
W
X
X51638V14
X51638S8-2.7A
-40oC - 85oC
X51638S8I-2.7A
14L TSSOP
0oC - 70oC
X51638V14-2.7A
8L SOIC
0oC - 70oC
X51638S8-2.7
o
o
14L TSSOP
0 C - 70 C
X51638V14-2.7
8L SOIC
0oC - 70oC
X51638S8-1.8
14L TSSOP
0oC - 70oC
X51638V14-1.8
Part Mark Information
X51638
X51638S8I
P = 8-Pin DIP
Blank = 8-Lead SOIC
V = 14 Lead TSSOP
Blank = 5V ±10%, 0°C to +70°C, VTRIP=4.25-4.5
AL=5V±10%, 0°C to +70°C, VTRIP = 4.5-4.75
I = 5V ±10%, –40°C to +85°C, VTRIP=4.25-4.5
AM = 5V ±10%, –40°C to +85°C, VTRIP=4.5-4.75
F = 2.7V to 5.5V, 0°C to +70°C, VTRIP=2.55-2.7
AN = 2.7V to 5.5V, 0°C to +70°C, VTRIP=2.85-3.0
G = 2.7V to 5.5V, –40°C to +85°C, VTRIP=2.55-2.7
AP = 2.7V to 5.5V, –40°C to +85°C, VTRIP=2.85-3.0
AG = 1.8V to 3.6V, 0°C to +70°C, VTRIP=1.7-1.8
AH = 1.8V to 3.6V, –40°C to +85°C, VTRIP=1.7-1.8
20
X51638
LIMITED WARRANTY
Devices sold by Xicor, Inc. are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. Xicor, Inc.
makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the
described devices from patent infringement. Xicor, Inc. makes no warranty of merchantability or fitness for any purpose. Xicor, Inc. reserves the
right to discontinue production and change specifications and prices at any time and without notice.
Xicor, Inc. assumes no responsibility for the use of any circuitry other than circuitry embodied in a Xicor, Inc. product. No other circuits, patents,
licenses are implied.
U.S. PATENTS
Xicor products are covered by one or more of the following U.S. Patents: 4,263,664; 4,274,012; 4,300,212; 4,314,265; 4,326,134; 4,393,481;
4,404,475; 4,450,402; 4,486,769; 4,488,060; 4,520,461; 4,533,846; 4,599,706; 4,617,652; 4,668,932; 4,752,912; 4,829, 482; 4,874, 967;
4,883, 976. Foreign patents and additional patents pending.
LIFE RELATED POLICY
In situations where semiconductor component failure may endanger life, system designers using this product should design the system with
appropriate error detection and correction, redundancy and back-up features to prevent such an occurence.
Xicor's products are not authorized for use in critical components in life support devices or systems.
1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain
life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably
expected to result in a significant injury to the user.
2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the
failure of the life support device or system, or to affect its safety or effectiveness.
21