[sdiy] Simple voltage controlled clock/counter

[Justin Owen]

Hello,

I have a need for a 'clock' of sorts - something to drive some counters, clock dividers and some other assorted logic bits'n'bobs.

It needs to...

Output a square wave between 0 and 5V-ish
Voltage controlled and linear - i.e. if 1V = 100Hz then 2V = 200Hz
Capable of low frequencies - say, approx. 10BPM (0.17Hz) to 300BPM (5 Hz)
Ideally w/- PWM
Some sort of sync or reset facility

Is my best solution to try and get an established VCO schematic down that low/slow?
Is there a CMOS contender - the 4046 perhaps?
Is this one of those things that would be better/easier to do in digital?
..or something else entirely?

Thanks in advance,

Justin