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Hot!MCP4651 5Kohm DigitalPot used for Gain adjustment of an Opamp

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2020/04/24 09:58:09 (permalink)

MCP4651 5Kohm DigitalPot used for Gain adjustment of an Opamp

 Hi There, I will apreciate if i can resolve this problem of mine, 
I have a NE5532 op-amp gain circuit attached (Digital Pot Connection.png) which is fed by +12 /-12 Volt in the rails. My input to the opamp Vin  is a ground referenced 0.3 Vrms to 1.5 V rms  audio signal. The MCP4651 P0A pin voltage is varying between  0.3 v rms or 1.5 Vrms according to the applied Audio signal level and is in the range of VDD/VSS voltage limits of the MCP4651. 
The MCP4651 5 Kohm digital potentiometer is on rheostat mode and  has  0 volt on the VSS pins  and 3.3dc  or 5 V dc ( not decided yet) on the VDD pins. 
Question 1 -  will the audio signal be amplified properly both positive and negative side  with a gain of 2 to 33 dB with the MCP4651 5 kohm version which the digital pot is not fed with a symetrical +- 12 Vdc power supply but with a voltage of 5 V dc maximum without any problem?
Question 2 - The MCP4651 is communicating with pic32MX795 through I2C lines, and pic32 is on 3.3 V dc supply. Will MCP4651 have a problem on the communication if it is supplied with  5 Volt Dc. 
Thank  you for your comments.

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    Re: MCP4651 5Kohm DigitalPot used for Gain adjustment of an Opamp 2020/04/28 16:46:37 (permalink)
    Datasheet tables on pages 5 and 11 hold the answers. Also absolute max specs.
    But, no and yes.
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