CD74FCT244, CD74FCT244AT

BiCMOS OCTAL BUFFERS/LINE DRIVERS

WITH 3-STATE OUTPUTS

SCBS722B – JULY 2000 – REVISED AUGUST 2003

4

POST OFFICE BOX 655303

PARAMETER MEASUREMENT INFORMATION

3 V

3 V

0 V

0 V

th

tsu

VOLTAGE WAVEFORMS

SETUP AND HOLD TIMES

Data Input

tPLH

tPHL

tPHL

tPLH

VOH

VOH

VOL

VOL

3 V

0 V

1.5 V

1.5 V

Input

Out-of-Phase

Output

In-Phase

Output

Timing Input

VOLTAGE WAVEFORMS

PROPAGATION DELAY TIMES

INVERTING AND NONINVERTING OUTPUTS

Output

Control

Output

Waveform 1

(see Note B)

Output

Waveform 2

(see Note B)

VOL

VOH

tPZL

tPZH

tPLZ

tPHZ

≈3.5 V

0 V

1.5 V

VOL + 0.3 V

1.5 V

≈0 V

3 V

VOLTAGE WAVEFORMS

ENABLE AND DISABLE TIMES

LOW- AND HIGH-LEVEL ENABLING

tPLH/tPHL

tPLZ/tPZL

tPHZ/tPZH

Open Drain

Open

7 V

Open

7 V

TEST

S1

3 V

0 V

1.5 V

tw

VOLTAGE WAVEFORMS

PULSE DURATION

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

≤ 1 MHz, ZO = 50 Ω, tr and tf = 2.5 ns.

D. The outputs are measured one at a time with one input transition per measurement.

E. tPLZ and tPHZ are the same as tdis.

F. tPZL and tPZH are the same as ten.

G. tPHL and tPLH are the same as tpd.

From Output

Under Test

CL = 50 pF

(see Note A)

LOAD CIRCUIT FOR

3-STATE AND OPEN-DRAIN OUTPUTS

S1

7 V

500

Ω

GND

From Output

Under Test

CL = 50 pF

(see Note A)

Test

Point

LOAD CIRCUIT FOR

TOTEM-POLE OUTPUTS

Open

VOH – 0.3 V

1.5 V

1.5 V

1.5 V

1.5 V

1.5 V

1.5 V

1.5 V

1.5 V

500

Ω

500

Ω

1.5 V

1.5 V

VOLTAGE WAVEFORM

INPUT RISE AND FALL TIMES

1.5 V

1.5 V

10%

10%

90%

90%

3 V

0 V

tr

tf

Figure 1. Load Circuit and Voltage Waveforms