Q: TPS62321 DC-DC converter and placing device into PWM mode. by 1621419

For the TPS62321 DC-DC converter, does using an external clock on the MODE/SYNC pin place the device into PWM mode or PFM mode?


A: Re: TPS62321 DC-DC converter and placing device into PWM mode. by 1090425

Yes, syncing the device to an external clock forces PWM operation: "During synchronization, the mode is set to fixed-frequency operation and the P-channel MOSFET turnon is synchronized to the falling edge of the external clock." page 16

Fixed frequency means no power save mode.  This is why you sync--you want your noise to be low at a specific frequency.  This is not the case with power save mode.