How are you all doing?
I for one am in need of your expertise.
Initially I planned to use chunky SMD ceramic caps but then i learned those are darn voltage dependent (unless C0G but those >1uF just barely exist). I dont want to make PCB space for two film caps so that leaves Electrolytic and... Tantalum?
Either would allow C11&12 to be 10uF easily fitting in a 2220 sized space. Also keeping in mind C12 can be diode clamped to ground so the voltage rating can be low. Additionally a small value C0G ceramic could be use to bypass C11&12.
This particular low ESR Tantalum cap range seems reasonable for audio frequencies:
https://ksim3.kemet.com/capacitor-simulation?pn=T495C107K006ATE150&disty=mouser
DC servo Implementation:
Of course tantalum caps are polar, so two should be placed in series, but since the Vswing will only be +-0.7V cant we just use the one?
Dabble with electrolithic, tantalum or other types, or go for the huge film caps anyway?
Feel free to share your opinions
Much thanks and cheers,
Ruben
I for one am in need of your expertise.
Initially I planned to use chunky SMD ceramic caps but then i learned those are darn voltage dependent (unless C0G but those >1uF just barely exist). I dont want to make PCB space for two film caps so that leaves Electrolytic and... Tantalum?
Either would allow C11&12 to be 10uF easily fitting in a 2220 sized space. Also keeping in mind C12 can be diode clamped to ground so the voltage rating can be low. Additionally a small value C0G ceramic could be use to bypass C11&12.
This particular low ESR Tantalum cap range seems reasonable for audio frequencies:
https://ksim3.kemet.com/capacitor-simulation?pn=T495C107K006ATE150&disty=mouser
DC servo Implementation:
Of course tantalum caps are polar, so two should be placed in series, but since the Vswing will only be +-0.7V cant we just use the one?
Dabble with electrolithic, tantalum or other types, or go for the huge film caps anyway?
Feel free to share your opinions
Much thanks and cheers,
Ruben
Are you using the other half of U1? You could implement a G = -1 inverter and then need only one cap in the integrator.
Thats definitely an option. I was gonna go for OP1641 single opamp. Ive implemented the non inverting integrator before so i trust it.
Also the layout turned out so damn nice.
Time Constant caps are C1 and C2 here. U1 the DC servo.
Also the layout turned out so damn nice.
Time Constant caps are C1 and C2 here. U1 the DC servo.
Well they exist but seem hard to source at the moment... 1uF PPS is a possibility for film caps, I found a couple in 2824 size at Mouser
Distortion isn't so much an issue in a DC servo, but MLCC ceramics other than C0G can be fairly microphonic...
A 1uF 100V polyester capacitor is not large.
https://www.digikey.com/en/products/detail/kemet/R82EC4100AA70J/9685242
Ed
https://www.digikey.com/en/products/detail/kemet/R82EC4100AA70J/9685242
Ed
Thank you . The S being silicone?
I found these gems.
https://nl.mouser.com/datasheet/2/977/e_MU-1600877.pdf
https://nl.mouser.com/datasheet/2/977/e_MU-1600877.pdf
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