SN54HCT126, SN74HCT126

QUADRUPLE BUS BUFFER GATES

WITH 3STATE OUTPUTS

SCLS070A − NOVEMBER 1988 − REVISED NOVEMBER 1990

4

POST OFFICE BOX 655303

POST OFFICE BOX 1443

PARAMETER MEASUREMENT INFORMATION

VOLTAGE WAVEFORMS

PROPAGATION DELAY TIMES

1.3 V

10%

3 V

≈ VCC

VOL

0 V

Input

(See Note B)

Output

(See Note C)

1.3 V

tPZL

tPLZ

VOLTAGE WAVEFORMS

ENABLE AND DISABLE TIMES

VOH

≈ 0 V

1.3 V

1.3 V

tPZH

tPHZ

Output

(See Note C)

From Output

Under Test

RL

VCC

S1

S2

LOAD CIRCUIT

PARAMETER

CL

tPZH

tpd or tt

tdis

ten

tPZL

tPHZ

tPLZ

1 k

Ω

1 k

Ω

50 pF

or

150 pF

50 pF

Open

Closed

RL

S1

Closed

Open

S2

Open

Closed

Closed

Open

50 pF

or

150 pF

Open

Open

−−

NOTES: A. CL includes probe and jig capacitance.

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

≤ 1 MHz, ZO = 50 Ω, tr ≤ 6 ns, tf ≤ 6 ns.

C. 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.

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

CL

(see Note A)

1.3 V

1.3 V

1.3 V

3 V

VOH

VOL

0 V

tr

tf

Input

Output

1.3 V

tPLH

tPHL

90%

Figure 1. Load Circuit and Voltage Waveforms