ON Semiconductor CAT872 User Manual

CAT872EVB
CAT871, CAT872 Reset
Generator Evaluation Board
User's Manual

Introduction

This document describes the CAT871, CAT872
Evaluation boards for the ON Semiconductor CAT87x
Reset Generators. The functionality and major parameters
of the CAT87x can be evaluated with the CAT872EVAL
board.
The CAT87x are two input reset generators designed to
restart microprocessor and microcontroller based systems.
The devices monitor two inputs and generate the reset
pulse after the two inputs are held low for a preset minimum
time. The CAT87x reset pulse widths are respectively 2.2 ms
(CAT871) and 70 ms (CAT872). The RESET output is also
capable of sinking up to 3 mA of current.
Additional details can be found in the CAT871 data sheet.

Board Hardware

The evaluation board consists of a CAT871, CAT872 that
generates the reset pulse when both push-buttons, MR1 and
MR2, are held low.
The VDD test point is connected to the VDD supply. The
voltage range is 1.65 V to 5.5 V.
The RESET output and MR1 input are pulled high to VDD
by resistors R1 and R2. Push-buttons MR1 and MR2 pull the
MR1 and MR2 inputs low when pressed. Optionally, the
MR1 and MR2 inputs can be applied to the test points
T_MR1 and T_MR2, respectively.
The CAT87xEVAL can only be configured in stand-alone
mode. Figure 1 shows the CAT87x evaluation board and the
Figure 2 shows the evaluation board schematic.
© ON Semiconductor Components Industries, LLC, 2012
January, 2012 − Rev. 1
EVAL BOARD USER'S MANUAL
Figure 1. CAT87xEVAL Board
Figure 2. CAT87xEVAL Board Schematic
1
http://onsemi.com
Publication Order Number:
EVBUM2053/D