EXAMPLE OF TYPICAL APPLICATION
PROGRAMMABLE DIVIDE-BY-N COUNTER
M54/M74HC40102/40103
•
fOUT
=
fIN
N+
1
•Timing chart when N = ”3”
(J0, J1 = VCC, J2 – J7 = GND)
PARALLEL CARRY CASCADING
• HC40102... 1/2 to 1/100 are dividable
• HC40103... 1/2 to 1/256 are dividable
* At synchronous cascade connection, huzzerd occurs at C0 output after its second stage when digitplace changes, due to delay arrival. Therefore,
take gate from HC32 or the like, not from C0 output at the rear stage directly.
PROGRAMMABLE TIMER
Note :The above formula does not take into account the phase of clock input. Therefore, the real pulse width is the distance between the
above formula-1/fIN ∼ the above formula.
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