SN74LS221J Datasheet, PDF (11/27 Pages) Texas Instruments – DUAL MONOSTABLE MULTIVIBRATORS WITH SCHMITT-TRIGGER INPUT

SN54221, SN54LS221, SN74221, SN74LS221
DUAL MONOSTABLE MULTIVIBRATORS
WITH SCHMITTĆTRIGGER INPUTS
SDLS213B − DECEMBER 1983 − REVISED NOVEMBER 2004
PARAMETER MEASUREMENT INFORMATION
3V
B†
0V
≥ 50 ns
≥ 50 ns
3V
CLR
0V
VOH
Q
VOL
CONDITION 4: TRIGGERING FROM POSITIVE TRANSITION OF CLR
A‡
CLR
Q
Q
tw
≥ 60 ns
tPLH
tPHL
tPHL
tPLH
CONDITION 5: TRIGGER FROM A, THEN CLR
3V
0V
3V
0V
VOH
VOL
VOH
VOL
A‡
tw
Q
tw
Q
3V
0V
VOH
VOL
VOH
VOL
† _{A is low.}
‡ _{B and CLR are high.}
CONDITION 6: TRIGGER FROM A
NOTES: A. Input pulses are supplied by generators having the following characteristics: PRR ≤ 1 MHz, ZO ≈ 50Ω; for SN54/74221, tr ≤ 7 ns,
tf ≤ 7 ns, for SN54/74LS221, tr ≤ 15 ns, tf ≤ 6 ns.
B. All measurements are made between the 1.5-V points of the indicated transitions for the SN54/74221 or between the 1.3-V points
for the SN54/74LS221.
Figure 1. Switching Characteristics (Continued)
• POST OFFICE BOX 655303 DALLAS, TEXAS 75265
11