This is information on a product in full production.

September 2013

DocID008216 Rev 3

1/13

HCF4021

Asynchronous parallel input or synchronous serial-in/serial-out

8-stage static shift register

Datasheet

Features

 Medium speed operation: 12 MHz (typ.) clock

 Fully static operation

 8 master-slave flip-flops plus output buffering

and control gating

 Quiescent current specified up to 20 V

 5 V, 10 V, and 15 V parametric ratings

 100% tested for quiescent current

 ESD performance

– CDM: 1 kV

– HBM: 2 kV

– MM: 200 V

Applications

 Automotive

 Industrial

 Computer

 Consumer

Description

The HCF4021 is a monolithic integrated circuit

fabricated in metal oxide semiconductor

technology available in PDIP-16 and SO-16

packages.

This device is an 8-stage parallel or serial-

input/serial-output register having common clock

and parallel/serial control inputs, a single serial

data input, and individual parallel "jam" inputs to

each register stage. Each register stage is a D-

type, master-slave flip-flop in addition to an output

from stage 8. "Q" outputs are also available from

stages 6 and 7. Serial entry is synchronous with

the clock but parallel entry is asynchronous.

In this device, entry is controlled by the

parallel/serial control input. When the

parallel/serial control input is low, data are serially

shifted into the 8-stage register synchronously

with the positive transition of the clock line. When

the parallel/serial control input is high, data are

jammed into the 8-stage register via the parallel

input lines and synchronous with the positive

transition of the clock line. The clock input of the

internal stage is “forced” when asynchronous

parallel entry is made. Register expansion using

multiple packages is permitted.

PDIP-16

SO-16

Table 1. Device summary

Order code

Temperature range

Package

Packing

Marking

HCF4021M013TR

-55 ° C to +125 ° C

SO-16

Tape & reel

HCF4021

1. Qualification and characterization according to AEC Q100 and Q003 or equivalent, advanced screening according to AEC

Q001 & Q002 or equivalent.

-40 ° C to +125 ° C

SO-16

(automotive grade)(1)

HCF4021Y

HCF4021BEY

-55 ° C to +125 ° C

PDIP-16

Tube

HCF4021BE

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