SN74LVC821A

10-BIT BUS-INTERFACE FLIP-FLOP

WITH 3-STATE OUTPUTS

SCAS304F – MARCH 1993 – REVISED JUNE 1998

8

POST OFFICE BOX 655303

PARAMETER MEASUREMENT INFORMATION

VOH

VOL

th

tsu

From Output

Under Test

CL = 50 pF

(see Note A)

LOAD CIRCUIT

S1

6 V

Open

GND

500

Ω

500

Ω

tPLH

tPHL

Output

Control

(low-level

enabling)

Output

Waveform 1

S1 at 6 V

(see Note B)

Output

Waveform 2

S1 at GND

(see Note B)

tPZL

tPZH

tPLZ

tPHZ

1.5 V

1.5 V

1.5 V

1.5 V

2.7 V

0 V

1.5 V

1.5 V

VOH

VOL

0 V

1.5 V

VOL + 0.3 V

1.5 V

VOH – 0.3 V

0 V

1.5 V

2.7 V

0 V

1.5 V

1.5 V

0 V

2.7 V

0 V

1.5 V

1.5 V

tw

Input

2.7 V

2.7 V

3 V

VOLTAGE WAVEFORMS

SETUP AND HOLD TIMES

VOLTAGE WAVEFORMS

PROPAGATION DELAY TIMES

VOLTAGE WAVEFORMS

PULSE DURATION

VOLTAGE WAVEFORMS

ENABLE AND DISABLE TIMES

Timing

Input

Data

Input

Output

Input

tpd

tPLZ/tPZL

tPHZ/tPZH

Open

6 V

GND

TEST

S1

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.

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

E. tPLZ and tPHZ are the same as tdis.

F. tPZL and tPZH are the same as ten.

G. tPLH and tPHL are the same as tpd.

Figure 3. Load Circuit and Voltage Waveforms