SN74ALS29827, SN74ALS29828

10-BIT BUFFERS AND BUS DRIVERS

WITH 3-STATE OUTPUTS

SDAS095B – JANUARY 1986 – REVISED JANUARY 1995

4

POST OFFICE BOX 655303

PARAMETER MEASUREMENT INFORMATION

LOAD CIRCUIT

R1

1 k

Ω

All Diodes

1N916 or 1N3064

From Output

Under Test

Test Point

S2

CL

(see Note A)

RL = 180 Ω

1.5 V

1.5 V

1.5 V

3 V

3 V

0

0

th

tsu

VOLTAGE WAVEFORMS

SETUP AND HOLD TIMES

Timing Input

Data Input

1.5 V

1.5 V

3 V

3 V

0

0

High-Level

Pulse

Low-Level

Pulse

tw

VOLTAGE WAVEFORMS

PULSE DURATIONS

1.5 V

1.5 V

tPHL

tPLH

tPLH

tPHL

Out-of-Phase

Output

1.5 V

1.5 V

1.5 V

1.5 V

1.5 V

1.5 V

3 V

0

VOL

VOH

VOH

VOL

In-Phase

Output

VOLTAGE WAVEFORMS

PROPAGATION DELAY TIMES

tPHZ

tPLZ

0.5 V

tPZL

tPZH

1.5 V

1.5 V

1.5 V

1.5 V

3 V

0

Output

Control

Waveform 1

(see Note B)

Waveform 2

(see Note B)

≈ 0

VOH

VOL

≈ 1.5 V

0.5 V

VOLTAGE WAVEFORMS

ENABLE AND DISABLE TIMES, 3-STATE OUTPUTS

VCC

S1

SWITCH POSITION TABLE

TEST

S1

S2

tPLH

tPHL

tPZH

tPZL

tPHZ

tPLZ

Closed

Closed

Open

Closed

Closed

Closed

Closed

Closed

Closed

Open

Closed

Closed

≈ 4.5 V

≈ 1.5 V

Input

NOTES: A. CL includes probe and jig capacitance.

B. Waveform 1 is for an output with internal conditions such that the output is low except when disabled by the output control.

Waveform 2 is for an output with internal conditions such that the output is high except when disabled by the output control.

C. All input pulses are supplied by generators having the following characteristics: PRR

≤ 10 MHz, ZO = 50 Ω, tr ≤ 2.5 ns, tf ≤ 2.5 ns.

Figure 1. Load Circuit and Voltage Waveforms