3.3V Power Supply Unit

Now a days 3.3V PSU is essential for microcontroller, programmable logic devices and for some analog components also (especially with some new ADCs). This is ultra-simple 3.3V power supply unit, which is suitable for above mentioned experiments. This power supply is based on, ON semiconductor’s MC33269T-3.3 LDO regulator and it is capable to deliver 3.3V output with maximum of 800mA current.

External view of 3.3V Power Supply

The PCB design supplied with this article is also compatible with LD1117V33 (also known as LD33V) LDO regulator and it can use with this PCB without any changes. Dimension of the given PCB is 70mm × 35mm and it is design with all through-hole components. Our PCB design for this PSU is available to download at google drive.

Maximum input voltage for this module is 20V (DC) for MC33269T-3.3 and 15V (DC) for LD1117V33 (or LD33V). In our unit we use 230V – 9V (1A) step down transformer as AC input for this unit.

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