Spin Semiconductor

In a different project I'm using 2 FV-1's but I must share control pots. It can be done with a single pot? (haven't tried yet, just evaluating possibilities but I don't want to use a dual pot). Thinked to buffer the CV signal and split it to both FV but the opamps offset will reduce the range of th...

The best way without modding the dev board would be to use another 8 Pin IC socket with wires soldered to the corresponding pins and piggyback this socket into the dev board eeprom socket. The wires can have a plug on the end which you just connect to your own production pcb.

Sweetalk wrote:
Great!!, what anti-alias filter are you using?.

Hi Sweetalk, In front of the FV-1 is a sallen-key filter which at 8khz.

I would use a cap and resistor on each input. The variance in DC offset could cause noise, to varying degrees. I made a last minute revision to the boards and added the option to be able to use either input configuration by not fitting some components and joining the inputs or to fit all the compon...

If you don't bypass the inputs there's Vcc/2 on each one. I'm tying both together and reading them both also. That is the method I have always used, with both inputs directly linked together. I was just wondering if this was good practice or may introduce a small hum. Would separating the inputs th...

If you don't bypass the inputs there's Vcc/2 on each one. I'm tying both together and reading them both also. That is the method I have always used, with both inputs directly linked together. I was just wondering if this was good practice or may introduce a small hum. Would separating the inputs th...

There shouldn't be any DC offset, the inputs are high pass filtered which would remove any DC that was present. After reading the Datasheet (again) I not sure the inputs are high pass filtered, the datasheet shows external high pass circuit on each input of course but this is not what I am really r...

I am using Both inputs, reading them both at 0.5 then summing them together then writing to a location to use later. I am not sure if this is correct but doing this seems to give a better s/n ratio and more headroom compared to reading one input at say 0.8. What I am really asking though is that hav...

I am using a mono input buffer/filter circuit into the FV-1 which drives both the ADC's pin 1 and 2 of the Fv-1. Pins 1&2 are connected directly to each other. I am now considering driving both inputs from the mono source but each of the ADC's having it's own DC decoupling from the mono input ra...

Have you checked the 3.3v regulator is actually putting out 3.3v. I'm not familiar with the pcb you are using but some 3.3v regs have a different pin out, so if it reversed you will be putting the wrong voltage on the FV-1 chip . This would cause it to overheat and possible damage.

If you run them in series it should be OK since the current will be the same but you may need to adjust the current limit resistor value slightly. You probably will not be able to run them in series. The forward voltage of two LEDs in series will be 3.6v or more, and there is only 3.3v powering the...

I wondered when setting up the input levels to the FV-1 if the clipping LED conducts what is the likelihood of damage to the FV-1 chip. I'm not clear on what you mean by this, the clip LED will turn on at about 6db below clipping if I remember correctly. Also can pin 5 sink enough current to fit 2 ...

I wondered when setting up the input levels to the FV-1 if the clipping LED conducts what is the likelihood of damage to the FV-1 chip. I am trying to get as close to the 3.3v input as possible without actually clipping the internal ADC but when using different instruments one can easily drive the l...

Great stuff guys thanks for posting, I will have a bit experiment with both over the weekend.

Cheers, at least is sounds quite do able even if needing to use two different LFO's

I should say the idea is for a tremolo so that one pot can select between the sine, triangle and square LFO waves while the other two pots control depth and rate.