Dilshan R Jayakody’s Web Log

In this post, we introduce simple and flexible, regulated low voltage power supply unit. This power supply has provision for 4 outputs such as 1.5V, 1.8V, 2.5V and 3.3V. We mainly build this low voltage power supply unit to test (and power-up) low voltage MCUs, CPLDs, and radio receivers. For this power supply, we choose 1.8V, 2.5V and 3.3V to get it compatible with most of the LVTTL/LVCMOS devices. Other than that, we include 1.5V because there are several analog ICs are available for that voltage level. This power supply unit is based on LM1117/AMS1117 voltage regulator series and for this design, we use AMS1117-1.5, AMS111-1.8, AMS1117-2.5, and AMS1117-3.3 fixed voltage regulators. Except to above regulators, this board can be used with AMS1117-2.85 and AMS1117-5.0 regulators. Internal view of the low voltage power supply unit. In our prototype, we use center-tapped 6V (1A) step down transformer with this power supply unit. All the wiring diagrams to transformer and rotary...