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Hello, everyone I'm trying to interface the SFH7050 sensor which contains 3 LEDs and 1 Photodiode.
I need to calculate the value of the feedback capacitor (Cf). To do this I have the next equation:
Rf is a value I can choose, C_d is on the datasheet so I need to figure out GBP and C_TIA from the PSoC's Op-amp Datasheet.
I've read it and I guess GBW_HI it's the GBP the equation mentions, am I right?
Plus I haven't been able to find the input capacitance of the Op-amp. Where can I find it?
Thanks
Solved! Go to Solution.
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Hi ,
For the opamp as the output is taken through a GPIO pin, the pin input capacitance is the dominating factor in the capacitance value.
Best Regards,
Vasanth
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Hi ,
For the opamp as the output is taken through a GPIO pin, the pin input capacitance is the dominating factor in the capacitance value.
Best Regards,
Vasanth
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Is it the same value if I'm looking for the input capacitance of the V_minus pin of the Op-amp?
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EfAv,
This should be helpful
https://www.analog.com/media/en/reference-design-documentation/desi…
And
Photodiode Circuit Design Wizard | Analog Devices
/odissey1
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Hi,
//Is it the same value if I'm looking for the input capacitance of the V_minus pin of the Op-amp?//
Yes, It is applicable for both the pins.
Best Regards,
Vasanth