Description

This reference design delivers a 48-V output: low-noise power supply for the phantom power application using the TPS61391 and TPS7A4101. TPS61391 is a 700-kHz PWM step-up converter that converts 3.3 V or 5 V to 48.5 V. TPS7A4101 is a 50-V tolerant input and 0.29-V drop LDO that steps 48.5 V down to 48 V and minimizes the output ripple. The design supports 48-V: 20-mA output power at 5-V input. The output ripple is approximately 8.4-mV: which is low for phantom power application.