MC74HC4040A Datasheet, PDF (6/8 Pages) ON Semiconductor – 12-Stage Binary Ripple Counter

MC74HC4040A
Clock
Reset
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
Q9
Q10
Q11
Q12
12
4
8
16
32
64 128 256 512 1024 2048 4096
Figure 6. Timing Diagram
APPLICATIONS INFORMATION
Time–Base Generator
A 60Hz sinewave obtained through a 100 K resistor
connected to a 120 Vac power line through a step down
transformer is applied to the input of the MC54/74HC14A,
Schmitt-trigger inverter. The HC14A squares–up the input
waveform and feeds the HC4040A. Selecting outputs Q5,
Q10, Q11, and Q12 causes a reset every 3600 clocks. The
HC20 decodes the counter outputs, produces a single
(narrow) output pulse, and resets the binary counter. The
resulting output frequency is 1.0 pulse/minute.
VCC
VCC
100 K
≥20 pF
110 Vac
15 – 30
Volts
1/6 of HC14A
HC4040A
13
Clock
Q5
12
Q10
10
Q11
9
Q12
1.0 Pulse/Minute
1
1/2
8 2 _1/2 6
Output
HC20
4
5
HC20
Figure 7. Time–Base Generator
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