Showing posts with label regulator. Show all posts
Showing posts with label regulator. Show all posts

Wednesday, November 19, 2014

Adjustable Switching Regulator Circuit with LM2576

The Adjustable Switching Regulator Circuit with LM2576 are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving 3A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, 15V, and an adjustable output version.
LM2576 IC Package
Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation and a fixed-frequency oscillator. The Adjustable Switching Regulator Circuit with LM2576 offers a high-efficiency replacement for popular three-terminal linear regulators. It substantially reduces the size of the heat sink, and in some cases no heat sink is required.


IC Switching Regulator Circuit with LM2576

A standard Adjustable Switching Regulator Circuit with LM2576 of inductors optimized for use with the LM2576 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies.

Other features include a guaranteed ±4% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring 50 μA (typical) standby current. The output switch includes cycle-by-cycle current limiting, as well as thermal shutdown for full protection under fault conditions.

Features Adjustable Switching Regulator Circuit with LM2576 :
- 3.3V, 5V, 12V, 15V, and adjustable output versions
- Adjustable version output voltage range,1.23V to 37V
- Guaranteed 3A output current
- Wide input voltage range, 40V up to 60V for HV version
- Requires only 4 external components
- 52 kHz fixed frequency internal oscillator
- TTL shutdown capability, low power standby mode
- High efficiency
- Uses readily available standard inductors
- Thermal shutdown and current limit protection
- P+ Product Enhancement tested
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Saturday, September 13, 2014

Build a High voltage Bucking Regulator Wiring diagram Schematic

This High voltage Bucking Regulator Circuit Diagram is basically tbe classic bucking regulator, except it uses a TMOS N-channel power FET for the chopper and creates its own supply for the gate control. Tht unique aspect of this schema is how it generates a separate supply for the gate schema, which must be greater than Vvv. 

When power is applied, C2 charges, through D2, to +12 V. At this time, Q1 is off and the voltage at point A is just below zero. When the pulse-modulated signal is applied, the optoisolator transistors, Q2 and Q3, supply a signal to Q1 that turns it on. The voltage at point A then goes to Vvn. C2 back-biases D2, and the voltage at point B becomes 12 V above Vnn· After Q1 is turned on, current starts to flow through L1 into C1, increasing until Q1 turns off. 

High voltage Bucking Regulator Circuit Diagram

High

The current still wants to flow through Ll, so the voltage at point A moves toward negative infinity, but is clamped by D1 to just below zero. Current flows less and less into C1, until Q1 turns on again. Q2 and Q3 drive Q1 `s gate between the voltages at point A and B, which is always a12 V swing, so Vcs max. is never exceeded. For proper operation, the 12-V supply has to be established before the pulse-width modulator signal is applied.
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Friday, August 22, 2014

Simple Lamp Dimmer Fan Regulator


This is the schema diagram of the simplest lamp dimmer or fan regulator.The schema is based on the principle of power control using a Triac.







BT 136Triac Necessary Data.



The schema works by varying the firing angle of the Triac . Resistors R1 ,R2 and capacitor C2 are associated with this.The firing angle can be varied by varying the value of any of these components.Here R1 is selected as the variable element .By varying the value of R1 the firing angle of Triac changes (in simple words, how much time should Triac conduct) changes.This directly varies the load power, since load is driven by Triac.The firing pulses are given to the gate of Triac T1 using Diac D1.
Notes

Assemble the schema on a good quality PCB or common board.The load whether lamp ,fan or any thing ,should be less than 200 Watts.To connect higher loads replace the Triac BT 136 with a higher Watt capacity Triac . All parts of the schema are active with potential shock hazard.So be careful.



Parts List

R1 1o K 1 Watt Resistor

R2 1o0 K Potentiometer (Variable Resistance)

C1 0.1 uF (500V or above ) Polyester Capacitor

T1 BT 136 Triac

D1 DB2 Diac

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