# Frequency Counter and Latch Problem

Discussion in 'General Electronics Chat' started by syee10, Mar 28, 2011.

1. ### syee10 Thread Starter Member

Mar 26, 2010
59
0
Suppose i have a frequency and i want to count it by using a decade counter, latch, BCD to 7 segment decoder and finally display the count on 7 segment display.
Theoretically if my input frequency to the decade counter is 1Hz, it will count 1 in 1s and if 10Hz, it will count 10 in 1s.
My question is, what will be the frequency of my latch if i want to make the counter count 1 for 1Hz and it count 10 for 10Hz in 1s? Will the frequency of my latch affect the counter? If yes, how to calculate the frequency into my latch?

2. ### beenthere Retired Moderator

Apr 20, 2004
15,815
283
There is a stepwise operation in a frequency counter.

1. The gate opens and the counter counts the input signal for the set period.
2. The gate closes and the count gets sent to the latches.
3. The count is displayed for a selectable period.
4. The counter is cleared and the gate is opened again for the next count.

Latching the count depends on the counting period - it is not independent of it.

In a simpler scenario, the BCD count is sent directly to the decoder/drivers. No latching has to be done.