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Frequency multiplication !!!

How to design a circuit that will be multiply a TTL signal's frequency
by 100, using 74HC4046 and 74HC390. Thank You for all responses.
 
S

SioL

Jan 1, 1970
0
How to design a circuit that will be multiply a TTL signal's frequency
by 100, using 74HC4046 and 74HC390. Thank You for all responses.

What is the signal's frequency? Is it within limits of 4046's internal VCO?

Is this homework?

SioL
 
P

Pawe³ Stobiñski

Jan 1, 1970
0
How to design a circuit that will be multiply a TTL signal's frequency
by 100, using 74HC4046 and 74HC390. Thank You for all responses.

Zobacz sobie artyku³ w PE 10/94.
 
J

John Popelish

Jan 1, 1970
0
How to design a circuit that will be multiply a TTL signal's frequency
by 100, using 74HC4046 and 74HC390. Thank You for all responses.

The 4046 has a pair of phase) detectors (two different characteristics
that compare two signals and produce a DC component in their output if
the frequencies do not match. It also contains a voltage controlled
oscillator to produce a frequency controlled by the Dc out of one of
the phase detectors. Divide that oscillator frequency by 100 and
compare it to the low frequency reference with one of the detectors,
and if a match is achieved, the oscillator will be running at 100
times the reference.

The data sheet for the 4046 has lots of advice on design details.

http://www.fairchildsemi.com/search/sitequery?qs=4046&key=short
 
Thank You for these two valuable links.
But frequency range of input TTL signals is from 2Hz to 2kHz. The
circuit that You had shown me is prepared for low frequencies
(1-150HZ). Will it be working in my case? Or What can I do to make it?
 
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