Philips 74HCT299U, 74HCT299N, 74HCT299DB, 74HCT299D, 74HC299N Datasheet

DATA SH EET

Product specification
File under Integrated Circuits, IC06

December 1990

INTEGRATED CIRCUITS

74HC/HCT299

8-bit universal shift register; 3-state

For a complete data sheet, please also download:

•The IC06 74HC/HCT/HCU/HCMOS Logic Family Specifications

•The IC06 74HC/HCT/HCU/HCMOS Logic Package Information

•The IC06 74HC/HCT/HCU/HCMOS Logic Package Outlines

December 1990 2

Philips Semiconductors Product specification

8-bit universal shift register; 3-state 74HC/HCT299

FEATURES

• Multiplexed inputs/outputs provide improved bit density

• Four operating modes:

– shift left
– shift right
– hold (store)
– load data

• Operates with output enable or at high-impedance
OFF-state (Z)

• 3-state outputs drive bus lines directly

• Can be cascaded for n-bits word length

• Output capability: bus driver (parallel I/Os),

standard (serial outputs)

• ICC category: MSI

GENERAL DESCRIPTION

The 74HC/HCT299 are high-speed Si-gate CMOS devices
and are pin compatible with low power Schottky TTL
(LSTTL). They are specified in compliance with JEDEC
standard no. 7A.

The 74HC/HCT299 contain eight edge-triggered D-type
flip-flops and the interstage logic necessary to perform
synchronous shift-right, shift-left, parallel load and hold
operations. The type of operation is determined by the
mode select inputs (S

0

and S1), as shown in the mode
select table.
All flip-flop outputs have 3-state buffers to separate these
outputs (I/O0 to I/O7) such, that they can serve as data
inputs in the parallel load mode. The serial outputs (Q0 and
Q7) are used for expansion in serial shifting of longer
words.

A LOW signal on the asynchronous master reset input
(MR) overrides the Sn and clock (CP) inputs and resets the
flip-flops. All other state changes are initiated by the rising
edge of the clock pulse. Inputs can change when the clock
is either state, provided that the recommended set-up and
hold times, relative to the rising edge of CP, are observed.

A HIGH signal on the 3-state output enable inputs (OE1 or
OE2) disables the 3-state buffers and the I/On outputs are
set to the high-impedance OFF-state. In this condition, the
shift, hold, load and reset operations can still occur. The
3-state buffers are also disabled by HIGH signals on both
S0 and S1, when in preparation for a parallel load
operation.

QUICK REFERENCE DATA

GND = 0 V; T

amb

=25°C; tr=tf= 6 ns

SYMBOL PARAMETER CONDITIONS

TYPICAL

UNIT

HC HCT

t

PHL/ tPLH

propagation delay CL= 15 pF; VCC=5 V

CP to Q

0

, Q

7

20 19 ns

CP to I/O

n

20 19 ns

t

PHL

MR to Q0, Q7 or I/O

n

20 23 ns

f

max

maximum clock frequency 50 46 MHz

C

I

input capacitance 3.5 3.5 pF

C

I/O

input/output capacitance 10 10 pF

C

PD

power dissipation capacitance per package notes 1 and 2 120 125 pF

Notes

1. CPD is used to determine the dynamic power
dissipation (PD in µW):

PD=CPD× V

CC

2

× fi+ ∑ (CL× V

CC

2

× fo) where:
fi= input frequency in MHz
fo= output frequency in MHz
∑ (CL× V

CC

2

× fo) = sum of outputs
CL= output load capacitance in pF
VCC= supply voltage in V

2. For HC the condition is V

I

= GND to V

CC

For HCT the condition is VI= GND to VCC− 1.5 V

ORDERING INFORMATION

See

“74HC/HCT/HCU/HCMOS Logic Package

Information”

.

December 1990 3

Philips Semiconductors Product specification

8-bit universal shift register; 3-state 74HC/HCT299

PIN DESCRIPTION

PIN NO. SYMBOL NAME AND FUNCTION

1, 19 S

0

, S

1

mode select inputs

2, 3

OE1, OE

2

3-state output enable inputs (active LOW)

7, 13, 6, 14, 5, 15, 4, 16 I/O

0

to I/O

7

parallel data inputs or 3-state parallel outputs (bus driver)

8, 17 Q

0

, Q

7

serial outputs (standard output)

9

MR asynchronous master reset input (active LOW)
10 GND ground (0 V)
11 D

SR

serial data shift-right input
12 CP clock input (LOW-to-HIGH, edge-triggered)
18 D

SL

serial data shift-left input
20 V

CC

positive supply voltage

Fig.1 Pin configuration. Fig.2 Logic symbol. Fig.3 IEC logic symbol.

December 1990 4

Philips Semiconductors Product specification

8-bit universal shift register; 3-state 74HC/HCT299

MODE SELECT TABLE

Notes

1. H = HIGH voltage level
L = LOW voltage level
X = don’t care
↑ = LOW-to-HIGH CP transition

INPUTS

RESPONSE

MR S

1

S

0

CP

L X X X asynchronous reset; Q

0−Q7

= LOW

H
H
H
H

H
L
H
L

H
H
L
L

↑
↑
↑

X

parallel load; I/O

n

→ Q

n

shift right; DSR→ Q0, Q0 → Q1 etc.
shift left; DSL→ Q7, Q7→ Q6 etc.
hold

Fig.4 Functional diagram.