HCF4541B
6/10
DYNAMIC ELECTRICAL CHARACTERISTICS (T
amb
= 25°C, C
L
= 50pF, R
L
= 200KΩ, t
r
= t
f
= 20 ns)
(*) Typical temperature coefficient for all V
DD
value is 0.3 %/°C.
DIGITAL TIMER APPLICATION
A positive MASTER RESET pulse clears the
counter and latch. The Output goes high and
keeps up till the number of pulses, selected by A
and B , are counted. This circuit is retriggerable
and is as accurate as the input frequency. If a
more accurate circuit is desired, an external clock
can be used on pin 3. A set-up time equal to the
width of the one shot output is required
immediately following initial power up, during
which time the output will be high
Symbol Parameter
Test Condition Value (*) Unit
V
DD
(V)
Min. Typ. Max.
(2
8
)
t
PHL
t
PLH
Propagation Delay Time
(CLOCK to Q)
5 3.5 10.5
µ
s10 1.25 3.8
15 0.9 2.9
(2
16
)
t
PHL
t
PLH
Propagation Delay Time
(CLOCK to Q)
5618
µ
s10 3.5 10
15 2.5 7.5
t
THL
Transition Time 5 100 200
ns10 50 100
15 40 80
t
TLH
Transition Time 5 180 360
ns10 90 180
15 65 130
Master Reset, Clock Pulse
Width
5 900 300
ns10 300 100
15 225 85
f
CL
Maximum Clock Pulse
Input Frequency
51.5
MHz10 4
15 6
t
r,
t
f
Maximum Clock Pulse
Input Rise or Fall Time
5
Unlimited
µ
s10
15
