CAT1021, CAT1022, CAT1023
PIN FUNCTION
PIN DESCRIPTION
¯¯¯¯¯¯
(RESET CAT1021/23 Only)
Pin
Name
RESET/RESET: RESET OUTPUT
Function
¯¯¯¯¯¯
These are open drain pins and RESET can be used
as a manual reset trigger input. By forcing a reset
condition on the pin the device will initiate and
maintain a reset condition. The RESET pin must be
connected through a pull-down resistor, and the
¯¯¯¯¯¯
resistor.
NC
No Connect
¯¯¯¯¯¯
RESET
Active Low Reset Input/Output
Ground
VSS
SDA
SCL
Serial Data/Address
Clock Input
RESET pin must be connected through a pull-up
RESET Active High Reset Output (CAT1021/23)
SDA: SERIAL DATA ADDRESS
VCC
WP
Power Supply
The bidirectional serial data/address pin is used to
transfer all data into and out of the device. The SDA
pin is an open drain output and can be wire-ORed
with other open drain or open collector outputs.
Write Protect (CAT1021 only)
Manual Reset Input
¯¯¯
MR
WDI
Watchdog Timer Interrupt (CAT1023)
SCL: SERIAL CLOCK
Serial clock input.
OPERATING TEMPERATURE RANGE
¯¯¯
MR: MANUAL RESET INPUT
Industrial
-40ºC to 85ºC
Manual Reset input is a debounced input that can be
connected to an external source for Manual Reset.
Pulling the MR input low will generate a Reset
condition. Reset outputs are active while MR input is
low and for the reset timeout period after MR returns
to high. The input has an internal pull up resistor.
Extended -40ºC to 125ºC
WP (CAT1021 Only): WRITE PROTECT INPUT
When WP input is tied to VSS or left unconnected write
operations to the entire array are allowed. When tied
to VCC, the entire array is protected. This input has an
internal pull down resistor.
WDI (CAT1023 Only): WATCHDOG TIMER INTERRUPT
Watchdog Timer Interrupt Input is used to reset the
watchdog timer. If a transition from high to low or low
to high does not occur every 1.6 seconds, the RESET
outputs will be driven active.
CAT102X FAMILY OVERVIEW
Manual
Reset
Input Pin
Watchdog
Monitor
Pin
Write
Protection
Pin
Independent
Auxiliary
Voltage Sense
RESET:
Active High
and LOW
Device
Watchdog
EEPROM
CAT1021
CAT1022
CAT1023
CAT1024
CAT1025
CAT1026
CAT1027
SDA
SDA
WDI
2k
2k
2k
2k
2k
2k
2k
ꢁ ꢁ
ꢁ
ꢁ
ꢁ
ꢁ
ꢁ ꢁ
ꢁ ꢁ
ꢁ ꢁ
ꢁ
ꢁ
ꢁ ꢁ
ꢁ
WDI
ꢁ
For supervisory circuits with embedded 16k EEPROM, please refer to the CAT1161, CAT1162 and CAT1163
data sheets.
© Catalyst Semiconductor, Inc.
Characteristics subject to change without notice
3
Doc. No. MD-3009 Rev. M