3.3V Power Supply | Electronic Project Circuits

Posts Tagged ‘3.3V power supply’

A Compact 36-72V DC Input, 3.3V-10A Output Power Supply

The output of this power supply is an isolated 3.3V/10A output, produced from an input is 36-72V DC. Airflow is required at higher ambient temperatures to get the full rated power.

The topology used is a single transistor forward, with a reset winding on the transformer to reset the core. The maximum duty cycle is less than 50%. The design uses the MAX5052A PWM controller.

Read more original source: http://www.maxim-ic.com/appnotes.cfm/an_pk/2400

Be the first to comment - What do you think? Posted by admin - June 13, 2008 at 9:57 am

Categories: Power supply, Switching power supply Tags: 3.3V power supply, dc converter step down voltage, Switching power supply

Easy Power Supply Regulator 3.3V 1A with PNP Transistor

The is Fix dc voltage regulator about 3.3V at 1A,so easy very circuit.
I used normal electronics part,so used PNP transistor 2N456 or TIP42 or TIP2955,etc.
If do you want other dc voltage,you must change ZD1 : 5.6V for 5V out put.
I made use of a 6.3Vac transformer,The output of the transformer is rectified and smoothed using 1500uF or 2200uF capacitors.
The float-voltage measured here for the 6.3V transformer was 8.4V.
The unregulated DC is regulated by the Q1 PNP Transistor and ZD1 to give the regulated supply rails for the circuit.

If do you want detail more,please read in image circuits.

Be the first to comment - What do you think? Posted by admin - May 3, 2008 at 12:39 pm

Categories: Power supply Tags: 3.3V power supply, dc voltage regulator, PNP Transistor circuit

3.3V regualated supply using 6V

The figure shows the circuit, shamelessly copied off the datasheet provided by Microchip.

I have been more inventive with the parts. I had to get a modern P channel MOSFET from Texas Instruments because old hard drive boards were seriously deficient in this one critical component.

However, using the parts as specified would be necessary to get 1. A more compact layout 2. higher efficiency.

As it is, my circuit is small enough to fall off the desk and be lost among the crud on the floor. I feel an increase in efficiency to 90% would be wonderful, but three points less is good enough.

This small integrated circuit has a maximum tolerable input of around 12 volts. It has terminals for driving external power devices, and that makes it more versatile.

For example, replacing that inductor with a transformer and arranging things so that the bulk of the power and voltage is handled by a second hefty transistor and diode can make this little circuit control a power supply operating off the rectified mains.