Other Parts Discussed in Thread: SN74LV4046A, CD4046B
Does TI provide a model for their HC4046 family of PLLs?
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What do you mean prototype only?
I mean to say that there's no simulation model, so you must build a prototype to test your designs.
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.
t must have PFD with push-pull charge pump output.
The '4046 has at least 2 phase comparators (CD4046B has 2, CD74HC4046 and SN74LV4046A have 3).
Although I recommend using the 'LV4046, the datasheet for CD74HC4046 is much better and is a great resource for designing with the LV4046.
All of these devices have push-pull outputs, but none of them contain a charge pump.
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.