Part Number:TPS74901
Customer is seeing issues with PSRR performance with the TPS74901. Voltage ripple from switching regulator feeding the LDO is too high at the output.
Conditions: Vin = 4V, Vout = 3.3V, Vbias = 5V (zener), I_out = 2A.
Presently, there is no CSS cap on the device. Would adding a CSS cap help PSRR? Data sheet indicates output noise improves, but the impact on PSRR is not clear.
Are there other circuit adjustments that could improve PSRR such as increasing output capacitance?