© 2000 Fairchild Semiconductor Corporation

DS009533

www.fairchildsemi.com

April 1988

Revised October 2000

74F398 • 74F399

Quad 2-Port Register

General Description

The 74F398 and 74F399 are the logical equivalents of a

quad 2-input multiplexer feeding into four edge-triggered

flip-flops. A common Select input determines which of the

two 4-bit words is accepted. The selected data enters the

flip-flops on the rising edge of the clock. The 74F399 is the

16-pin version of the 74F398, with only the Q outputs of the

flip-flops available.

Features

s Select inputs from two data sources

s Fully positive edge-triggered operation

s Both true and complement outputs—74F398

Ordering Code:

Device also available in Tape and Reel. Specify by appending suffix letter “X” to the ordering code.

Connection Diagrams

74F398

74F399

Order Number

Package Number

Package Description

74F398SC

M20B

20-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-013, 0.300 Wide

74F398PC

N20A

20-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide

74F399SC

M16A

16-Lead Small Outline Integrated Circuit (SOIC), JEDEC MS-012, 0.150 Narrow

74F399SJ

M16D

16-Lead Small Outline Package (SOP), EIAJ TYPE II, 5.3mm Wide

74F399PC

N16E

16-Lead Plastic Dual-In-Line Package (PDIP), JEDEC MS-001, 0.300 Wide