I'm not familiar with electronics at all, and would like to get some ideas to implement frequency multiplication of LVCMOS.

I want to multiply the frequency in the range of 250 kHz by a factor of 10 or 20 and the input and output signals should be in phase with less jitter.

Most of commercially available PLL clock synthesizer set the lowest input frequency limit at MHz and hence kHz frequency signals are not accepted.

I'm wondering whether any products that I have not found for my task? If I need to design a circuit by myself, what is a suitable IC?

Much appreciated for your kind help and suggestions.


  • \$\begingroup\$ Loop frequencies in the kilohertz are not at all unusual in radio PLLs as in the classic form that becomes your tuning step size, ie, channel spacing. Keep in mind however that you typically need to design such a PLL for a limited range of output frequencies. Your question is very short on specifics of requirement and application goal. \$\endgroup\$ – Chris Stratton Mar 1 at 2:37
  • \$\begingroup\$ Look at ti.com/lit/ds/symlink/sn74lv4046a.pdf and use it with an external divider. \$\endgroup\$ – crj11 Mar 1 at 2:49
  • \$\begingroup\$ It is easy to multiply this with less jitter, but do you have input jitter + BW and output jitter specs? and any other requirements lock time etc. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Mar 1 at 2:51
  • \$\begingroup\$ In general the output edges will track the input edges, because your div_10 discards 9 out of ten edges. A very slow loop filter may help reduce the jitter. \$\endgroup\$ – analogsystemsrf Mar 1 at 3:11
  • \$\begingroup\$ Back in the 1980s, Bosch built two way radios for the police in Germany. One model used a 4046 to multiply a 5kHz base frequency up into a range of around 4 MHz. There was then a couple of high frequency, fixed oscillators just below the actual 4M (74-77MHz and 84-87MHz) frequency range the radio operated in. Sum the synthsized frequency with the appropriate high frequency, and you got your channel frequency. The receiver had a lot of bleed through at 5kHz, though. Found that out the hard way when I had to install a voice inverter in some of those radios. \$\endgroup\$ – JRE Mar 1 at 6:43

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