TPA3245: Power Supply

Hello Akio,

My answers are below.

Q1: In standby mode of their application, GVDD and VDD are not supplied but they will continue supplying PVDD. Is there any problem?

A1: When GVDD or VDD is not supplied or have not reached the values stated in the Electrical Characteristics table, the device will put all of the half-bridge outputs to a high-impedance state and /FAULT will be asserted low. (This information can be found in Section 9.4.6 of the TPA3245 Datasheet).
Q2: If /RESET pin is low and supplying only PVDD, is the RESET function enabled?
A2: The /RESET function should still be enabled. It will remove the /FAULT initiated by the VDD UVP. (See section 9.4.8 of the TPA3245 Datasheet).

Q3: If they input signals to TPA3245 when GVDD and VDD are not supplied, does TPA3245 suffer any damage?
A3: No, the TPA3245 should not suffer any damage because the device will be put in Voltage Fault resulting in a high impedance state of the half-bridge outputs.

Q4: If /RESET pin is set low beforehand, can they down the powers without consideration of sequence

A4: The TPA3245 does not require a power-down sequence (see Section 11.3 of the datasheet). It is actually suggested practice to set the /RESET pin low before powering down.

Regards,

Dan