HD74HC4538 Datasheet, PDF (4/14 Pages) Hitachi Semiconductor – Dual Precision Retriggerable/Resettable Monostable Multivibrators

HD74HC4538
Switching Characteristics (C_L = 50 pF, Input t_r = t_f = 6 ns)
Ta = 25°C
Ta = –40 to +85°C
Item
Symbol V_CC (V) Min Typ Max Min
Max Unit
Test Conditions
Propagation delay t_PLH
time
2.0 — — 235
—
4.5 — 22 47
—
295 ns A or B to Q
59
6.0 — — 40
—
50
t_PHL
2.0 — — 260
—
4.5 — 23 52
—
325 ns A or B to Q
65
6.0 — — 44
—
55
t_PHL
2.0 — — 235
—
4.5 — 17 47
—
295
ns C_D to Q
59
6.0 — — 40
—
50
t_PLH
2.0 — — 235
—
4.5 — — 47
—
295
ns C_D to Q
59
6.0 — — 40
—
50
Pulse width
t_w
2.0
80 — —
100
—
ns A, B, C_D
4.5 16 — —
20
—
6.0 14 — —
17
—
Output pulse width t_WQ
3.0 — 150 —
—
5.0 — 100 —
—
—
ns R_X = 1 kΩ, C_X = 12 pF
—
3.0 — — —
—
5.0 — 1.3 —
—
—
µs R_X = 10 kΩ, C_X = 100 pF
—
3.0 — — —
—
5.0 — 9 —
—
—
µs R_X = 10 kΩ, C_X = 1000 pF
—
3.0 — — —
—
5.0 — 70 —
—
—
µs R_X = 10 kΩ, C_X = 10000 pF
—
Pulse width match ∆tWQ
5.0
— ±0.1 —
—
between circuits in
the same package
—
% R_X = 10 kΩ, C_X = 1000 pF
Caution in use: In order to prevent any malfunctions due to noise, connect a high frequency performance capacitor
between V_CC and GND, and keep the wiring between the External components and Cext, Rext/Cext pins
as short as possible.
Test Circuit
VCC
Input A
Pulse Generator
Zout = 50 Ω
Input B
Pulse Generator
Zout _{= 50} Ω
Input Clear
Pulse Generator
Zout = 50 Ω
VCC
Cext Rext
Cext Rext/Cext
Q
Output
C_L =
50 pF
Output
Q
Clear
C_L =
50 pF
Note : 1. C_L includes probe and jig capacitance.
Rev.2.00 Mar 30, 2006 page 4 of 13