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WEBENCH® Tools: which Frequency Multiplier should i choose?

Intellectual 710 points

Replies: 1

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Tool/software: WEBENCH® Design Tools

I need a Frequency Multiplier as following:

Operates From a Single 3.3 V or 5.5V 

Input Clock Frequencies From 5 to 50 Hz  of square wave

Output Clock Frequencies  at least multiples of the number ten. 

Operating  temperature at 0°C to 150°C will more better;

  • Hello chennangan,

    For a square wave of such low frequency, unless you need extremely low jitter, it makes the most sense to use a microcontroller to directly sample the square wave at much higher frequency and program the microcontroller as a digital PLL using a numerically-controlled oscillator as feedback.

    0°C to 150°C operation is a very challenging temperature range, and while there are some devices which can meet this requirement, they are quite expensive. The MSP430F2619S-HT, SM320F2812-HT, and SM320F28335-HT are essentially the only devices I found which are capable of the required temperature range.

    If you need lower jitter than a microcontroller can provide, or if you want a lower price, and you can afford to reduce the operating range to 125°C, something like the CD4046B coupled with a linear ramp-style voltage to frequency synthesizer and some CD4017B or CD4022B counters could make a stable low-frequency analog PLL.


    Derek Payne

    Texas Instruments