Question about TPA3110D2 GVDD Capacitor

1) Is it possible to change GVDD capacitor value larger, for example from 1uF to 220uF?  The customer would like to change the capacitor value due to sound tune.

2) When the system is powered on AVCC/PVCC rises to 12V final value over about 2.5 seconds.  Is there any concerning point on this including GVDD cap value?

Q: Re: TPA3110D2 GVDD Capacitor

The customer asked us additionally if it was possible to connect (47 ohm resistor in series with 22uF) in parallel with 1uF.  Is the connection acceptable?

A: Re: TPA3110D2 GVDD Capacitor

I can recommend limits for current drawn by the circuit the customer decides to use.

- The peak current must not be greater than 100mA in any case.  This applies during power up and also during power down, in case their VCC discharges before GVDD.

- Current to the GVDD cap must fall exponentially, to 10mA or less within 10mS after the intial peak.

Otherwise TPA3110D2 cannot remain reliable in the long term.  As long as their power supply rises as slowly as the voltage shown in the graph that they provided at the beginning of this case, the customer may see that it is OK to use the 220uF cap if they want to, but maybe not if their supply falls quickly on turn-off.  They will have to check this.

I expect they will find it is OK to add (22uF in series with 47ohms) in parallel with the normal 1uF.

Q: RE: TPA3110D2 GVDD Capacitor

I will tell the customer that they can use series resistor with 22uF as they think. And I will inform some detailed behavior of GVDD as you commented.