MCP4651 5K Rheostat Mode Question
Hi there i would appreciate if i can get some help to sort the following out in my circuit design ,
I have an non inverting mode NE 5532 op amp fed with symetric +12 / -12 Volts on the supply rails . The Audio input signal is between 0.3volt to 1.5 volt Rms on the non inverting pin. The MCP 4651 5Kohm digital pot connected is adjusting the Gain of the amplifier in the circuit between 1dB to 33 dB which i have taken design from the application note of Microchip Digital Potentiometer Design Guide. (Non inverting amplifier with digipot.png).
in my deisgn, MCP4651 is supplied with 0 volt on the VSS , +3.3 or +5 Volt DC (which i couldnt decide yet) on the VDD pin.
1- The DP0A pin voltage on the MCP4651 is around 0.3 to 1.5 Vrms maximum depending on my input pin on the op amp (in attached circuit diagram, Digital Pot Connection.png) . Due to the Audio signals with ground referenced input floating both positive and negative rails , and thinking that i am not overpassing the supply voltage of MCP4651 on the P0A pin, will this digital pot do the job to adjust the gain of the op amp without any problem? As we dont have any negative supply voltage on the MCP4651 VSS pin?
2- if it is ok to use MCP5651 5Kohm version without any problem in this circuit , Can i use 3.3 Volts to feed MCP4651 not to have a problem with I2C lines as all of my other devices are fed with 3.3 Volts with Pic32.
Thank you in advance.