S93WD462 Datasheet, PDF (11/14 Pages) Summit Microelectronics, Inc. – Precision Supply-Voltage Monitor and Reset Controller With a Watchdog Timer and 1k-bit Microwire Memory

S93WD462/S93WD463
Frequently the reset controller will be deployed on a PC board that provides a peripheral function to a system.
Examples might be modem or network cards in a PC or a PCMCIA card in a laptop. In instances like this the peripheral
card may have a requirement for a clean reset function to insure proper operation. The system may or may not provide
a reset pulse of sufficient duration to clear the peripheral or to protect data stored in a nonvolatile memory.
The I/O capability of the RESET pins can provide a solution. The system’s reset signal to the peripheral can be fed
into the S93WD462/WD463 and it in turn can clean up the signal and provide a known entity to the peripheral’s circuits.
The figure below shows the basic timing characteristics under the assumption the reset input is shorter in duration
than tPURST. The same reset output affect can be attained by using the active high reset input.
RESET#
Input
RESET#
Output
RESET
Output
t _PURST
2029 T fig09 2.0
When planning your resistor pull-up and pull-down values, use the following chart to help determine min. resistances.
Worst Case RESET Sink/Source Capabilities at Various VCC Levels
Parameter
Symbol
RESET# Output
V_OL
Voltage
RESET# Output
V_OL
Voltage
RESET Output
VOH
Voltage
Condition
VCC = 1.0V, IOL=100µA
VCC = 1.2V, IOL=100µA
VCC = 3.0V, IOL=500µA
VCC = 3.6V, IOL=500µA
VCC = 4.5V, IOL=750µA
VCC = 1.0V, IOL=100µA
VCC = 1.2V, IOL=150µA
VCC = 3.0V, IOL=750µA
VCC = 3.6V, IOL=1mA
VCC = 4.5V, IOL=1mA
VCC = 1.0V, IOH=400µA
VCC = 1.2V, IOH=800µA
VCC = 3.0V, IOH=800µA
VCC = 3.6V, IOH=800µA
VCC = 4.5V, IOH=800µA
Min
VCC-0.75
VCC-0.75
VCC-0.5
VCC-0.5
VCC-0.5
Typ
Max
0.3
0.3
0.3
0.3
0.3
0.4
0.4
0.4
0.4
0.4
Units
V
V
V
V
V
V
V
V
V
V
V
V
V
V
V
2029 PGM T5.0
SUMMIT MICROELECTRONICS, Inc.
2029 2.2 1/23/01
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