January 1995

2

Philips Semiconductors

Product specification

Octal transparent latch with 3-state outputs

HEF40373B

MSI

DESCRIPTION

The HEF40373B is an 8-bit transparent latch with 3-state

buffered outputs. The output stages have high current

output capability suitable for driving highly capacitive

loads. The latch outputs follow the data inputs when the

latch enable (E) is HIGH. When E is LOW, the data that

meets the set-up times is latched. The 3-state outputs are

controlled by the output enable input EO. A HIGH on

EO causes the outputs to assume a high impedance

OFF-state. The device features hysteresis on the E input

to improve noise rejection.

Schmitt-trigger action in the E input makes the circuit

highly tolerant to slower input rise and fall times.

The HEF40373B is pin and functionally compatible with

the TTL ‘373’ device.

Supply voltage range: 3 to 15 V.

Fig.1 Functional diagram.

Fig.2 Pinning diagram.

HEF40373BP(N):

20-lead DIL; plastic

(SOT146-1)

HEF40373BD(F):

20-lead DIL; ceramic (cerdip)

(SOT152)

HEF40373BT(D):

20-lead SO; plastic

(SOT163-1)

( ): Package Designator North America

PINNING

See Family Specifications

data inputs

E

latch enable input

EO

output enable input (active LOW)

3-state buffered outputs