CD4541B
Digital Timer Application
A positive pulse on MASTER RESET resets the counters
and latch. The output goes high and remains high until the
number of pulses, selected by A and B, are counted. This
circuit is retriggerable and is as accurate as the input fre-
quency. If additional accuracy is desired, an external clock
can be used on pin 3. A setup 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.
V
DD
1
C
TC
R
S
INPUT
AR
MR
2
3
4
5
6
7
14
13
12
11
10
9
8
B
A
82
80
70
60
50
40
30
R
TC
20
10
0
4 - 10
(0.102 - 0.254)
OUTPUT
t
85 - 93
(2.159 - 2.362)
79 - 87
(2.007 - 2.210)
0
10
20
30
40
50
60
70
80 88
FIGURE 3. DIGITAL TIMER APPLICATION CIRCUIT
NOTE: Dimensions in parentheses are in millimeters and are de-
rived from the basic inch dimensions as indicated. Grid graduations
are in mils (10
-3
inch).
FIGURE 4. DIMENSIONS AND PAD LAYOUT FOR CD4541B
5
TI [ TEXAS INSTRUMENTS ]
