[sdiy] Help with sawtooth convertor

[Tim Ressel]

So I would need a negative voltage to turn on a jfet, yes?

--tr

On 1/4/2019 12:47 AM, David G Dixon wrote:
> Why not just use a JFET?  I use 2N5485 for this, and it works a treat.
>
>> -----Original Message-----
>> From: Synth-diy [mailto:synth-diy-bounces at synth-diy.org] On
>> Behalf Of Tim Ressel
>> Sent: Thursday, January 03, 2019 6:15 PM
>> To: SYNTH DIY
>> Subject: [sdiy] Help with sawtooth convertor
>>
>> Hi,
>>
>> Once again my ignorance bites be. I have a triangle to saw
>> convertor that works very well:
>>
>> https://imgur.com/a/CutQtVC
>>
>> But the DG448 is smt (and  pricey) and I need a pth solution.
>> The DG448 is just shorting the op amp pin to ground. I have
>> seen circuits using npn transistors and stuff like 2N7000 but
>> I cannot get that to work. The signal at that spot is up to
>> +/- 10 volts. Does anyone know how to do this?
>>
>> Thanks!
>>
>>
>> --
>> --Tim Ressel
>> Circuit Abbey
>> timr at circuitabbey.com
>>
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>
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-- 
--Tim Ressel
Circuit Abbey
timr at circuitabbey.com