The design I have in mind will be battery operated, so I have found the TL972 (Datasheet Here) which only operates from 0 - 12 V. What I want this op-amp to do is to create a sawtooth/triangle wave generator to drive a VCO, namely the POS-535+ (Datasheet here). The frequency we want the VCO to output is around 300 - 400 MHz, and according to the figure named "Frequency and Tuning Sensitivity" in that datasheet, 2 - 7'ish volts will cover that output range of frequencies. (For the design, I want 1 - 8 V just to be on the safe side.
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I have researched all over the Internet, but the only op-amps I am seeing that will generate the desired waveforms swing and operate from negative voltages. I have tried those circuits, to no avail.
Technically, I could use an LDO voltage regulator to output a negative voltage for an op-amp, but this will add more complexity/cost to the circuit and will be considered as a last resort.
So designing this circuit isn't too easy as first we have to make the first portion of the op-amp create a square wave, and then the other will create the ramp. I'm not entirely sure how to do that and would like help/pointers on doing so. Unfortunately, I have no schematics thus far for reference as all the schematics I have seen are for op-amps that operate between negative to positive.
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Also, to generate a ramp wave of 1 - 8 V is pretty dang broad. If there is a better VCO that operates no more than 12 V and covers 300 - 400 MHz, please by all means recommend one to me if that is more convenient than designing a ramp wave that sweeps 1 - 8V.
Any help, guidance, or pointers is greatly appreciated! (Forgive my terminology if I misused some terms. Engineer in progress here.)