To avoid level shifting opamps I decided to power the teensy with a symmetrical power supply.
The teensy digital ground is at -1.66V and Teesy Vin pin is at 2.5V. Thus, the total voltage across Vin and GND is 4.16V. To correct DC offset errors, the analog ground (0V) is read at an analog pin of the teensy and subtracted from any signal that is read at any other analog input pins. The result is perfectly symmetrical waveforms around 0.
While that system is performing normally well, two teensies burned presumably because of a loose contact on the analog ground or positive supply.
I was wondering if I should add a resistor between the analog ground and the teensy analog input pin to reduce currents. But I'm not sure if the issue could stem from that ground connected to the input pin at all.
Any comments an this are welcome!
The teensy digital ground is at -1.66V and Teesy Vin pin is at 2.5V. Thus, the total voltage across Vin and GND is 4.16V. To correct DC offset errors, the analog ground (0V) is read at an analog pin of the teensy and subtracted from any signal that is read at any other analog input pins. The result is perfectly symmetrical waveforms around 0.
While that system is performing normally well, two teensies burned presumably because of a loose contact on the analog ground or positive supply.
I was wondering if I should add a resistor between the analog ground and the teensy analog input pin to reduce currents. But I'm not sure if the issue could stem from that ground connected to the input pin at all.
Any comments an this are welcome!
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