HCF4536B(2002) Ver la hoja de datos (PDF) - STMicroelectronics

Número de pieza

componentes Descripción

Lista de partido

HCF4536B
(Rev.:2002)

PROGRAMMABLE TIMER

STMicroelectronics 

HCF4536B

FUNCTIONAL TEST SEQUENCE

Inputs

Outputs

COMMENTS

Decade Out

In 1

Set

Reset

8-Bypass Q1 Thru

All 24 steps are in reset mode

Q24

H

L

H

H

L

Counter is in three 8-stage section in parallel

H

H

H

H

L

mode

L

H

H

H

L

First "H" to "L" Transition of Clock

H

L

H

H

H

255 "H" to "L" transitions are clocked in the

counter

L

H

H

H

H

The 255 "H" to "L" Transition

Counter converted back to 24 stages in series

mode.

L

L

L

L

H

Set and Reset must be connected together

and simultaneously go from "H" to "L"

H

L

L

L

H

In1 switches to a "H"

L

L

L

L

L

Counter Ripples from an all "H" state to an all

"L" state

FUNCTIONAL TEST SEQUENCE

Test function has been included for the reduction

of test time required to exercise all 24 counter

stages.This test function divides the counter into

three 8-stage section and 255 counts are loaded in

each of the 8-stage sections in parallel. All

flip-flops are now at a "H". The counter is now

returned to the normal 24-steps in series

configuration. One more pulse is entered into In1

which will cause the counter to ripple from an all

"H" state to an all "L" state.

TEST CIRCUIT

CL = 50pF or equivalent (includes jig and probe capacitance)

RL = 200KΩ

RT = ZOUT of pulse generator (typically 50Ω)

9/13

Share Link: