Philips Semiconductors
Dual precision monostable multivibrator
Preliminary specification
HEF4938B
AC CHARACTERISTICS
VSS = 0 V; Tamb = 25 °C; CL = 50 pF; input transition times ≤ 20 ns.
PARAMETER
VDD
(V)
SYMBOL MIN. TYP.
Propagation delay
I0, I1 to O
HIGH to LOW
Propagation delay
I0, I1 to O
LOW to HIGH
Propagation delay
CD to O
HIGH to LOW
Propagation delay
CD to O
LOW to HIGH
Recovery times
CD to I0, I1
Retrigger times
O, O to I0, I1
LOW to OFF
Minimum output
pulse width LOW
I0
Minimum output
pulse width LOW
I1
Output pulse width
O, O
5
10
tPHL
15
5
10
tPLH
15
5
10
tPHL
15
5
10
tPLH
15
5
10
tRCD
15
5
10 tRO
15
5
10
tWIOL
15
5
10
tWI1H
15
5
10 tWO
15
−
200
−
90
−
60
−
220
−
85
−
60
−
125
−
55
−
40
−
125
−
55
−
40
−
20
−
10
−
5
0
−
0
−
0
−
90
45
30
15
24
12
50
25
24
12
20
10
9.3 10.0
9.2
9.9
9.1
9.8
MAX.
460
180
120
440
190
120
250
110
80
250
110
80
40
20
10
−
−
−
−
−
−
−
−
−
10.6
10.5
10.4
UNIT
TYPICAL
EXTRAPOLATION
FORMULA
173 ns + (0.55 ns/pF) CL
ns 79 ns + (0.23 ns/pF) CL
52 ns + (0.16 ns/pF) CL
193 ns + (0.55 ns/pF) CL
ns 74 ns + (0.23 ns/pF) CL
52 ns + (0.16 ns/pF) CL
98 ns + (0.55 ns/pF) CL
ns 44 ns + (0.23 ns/pF) CL
32 ns + (0.16 ns/pF) CL
98 ns + (0.55 ns/pF) CL
ns 44 ns + (0.23 ns/pF) CL
32 ns + (0.16 ns/pF) CL
ns
ns
ns
ns
ms Rt = 100 kΩ; Ct = 100 nF
January 1995
5