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Thanks for the reply. What do you mean prototype only? They shouldn't be used for new designs? I'm looking for a PLL that will work in the 400kHz range, with or w/o an integral VCO. Any suggestions?
I'm looking for a PLL that will work in the 400kHz range, with or w/o an integral VCO. Any suggestions?
The '4046 will work at 400 kHz. The one thing to note is that this is a logic device, so your input and output should be square waves. I'd look at the SN74LV4046A, as that's the most modern option.
What about the CD4046B? Is there a disadvantage using a PLL w/o a charge pump. The charge pump will charge up the LF to a voltage to control the VCO. What I want to do is pull on the PFD output to induce a phase shift on the VCO. With a charge pump I can inject current into the output of PLL.
I think you're talking about an RF (sine wave) PLL, and I'm talking about a digital logic PLL (4046). They're similar, but my primary expertise is with the latter.
The CD4046B is designed for 15V operation, but it works from 3V to 18V. If I were operating with 5V or lower logic, I'd choose the SN74LV4046A.
This device will use a LPF to basically turn the pulse-chain output of the phase comparator into a DC signal that controls the VCO. You could use an analog adder circuit to modify that, but it's not something I've seen done before.
