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PARAMETER MEASUREMENT INFORMATION

From Output

Under Test

(see Note A)

LOAD CIRCUIT

S1

Open

GND

Data Input

Timing Input

0 V

0 V

0 V

Input

VOLTAGE WAVEFORMS

SETUP AND HOLD TIMES

VOLTAGE WAVEFORMS

PROPAGATION DELAY TIMES

INVERTING AND NONINVERTING OUTPUTS

VOLTAGE WAVEFORMS

PULSE DURATION

0 V

Input

Output

Waveform 1

(see Note B)

Output

Waveform 2

S1 at GND

(see Note B)

0 V

≈0 V

VOLTAGE WAVEFORMS

ENABLE AND DISABLE TIMES

LOW- AND HIGH-LEVEL ENABLING

Output

Output

Open

GND

TEST

S1

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

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

H. All parameters and waveforms are not applicable to all devices.

Output

Control

1.8 V

± 0.15 V

2.5 V

± 0.2 V

2.7 V

3.3 V

± 0.3 V

1 k

Ω

500

Ω

500

Ω

500

Ω

2

2

6 V

6 V

30 pF

30 pF

50 pF

50 pF

0.15 V

0.15 V

0.3 V

0.3 V

2.7 V

2.7 V

1.5 V

1.5 V

≤2 ns

≤2 ns

≤2.5 ns

≤2.5 ns

INPUTS

SN54LVC257A, SN74LVC257A

QUADRUPLE 2-LINE TO 1-LINE DATA SELECTORS/MULTIPLEXERS

WITH 3-STATE OUTPUTS

SCAS294N – JANUARY 1993 – REVISED JUNE 2005

Figure 1. Load Circuit and Voltage Waveforms

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