115 Vac Converter using NCL30100

This power supply Electronic Circuit Project is an very simple 115 Vac Converter, designed using the NCL30100 compact switching regulator controller designed for high brightness LED driver applications where efficiency and small size are very important.

115 Vac Converter Circuit Diagram:

 

The input voltage range is from 85 to 140 Vac and is rectified by bridge rectifier D1, D3, D4 and D6. C1 capacitor is used to limit current peaks generated during on time period. CX1, C2 and L1 are an EMI filter to protect mains against current spikes mainly generated by D2 if Q1 is turned on. The NCL30100 is powered through resistors R1 and R2.

The Vcc voltage is limited by D7and the maximum LED current is set by resistors R3, R4 and R5 (in this case Rsense is 0.33 Ω to reach higher accuracy). C3 capacitor is used to filter out spikes which are generated during the turn off of diode D2. It is recommended to use L2 with low series resistance since current is flowing through the inductor continuously and D2 should be selected for low forward voltage drop and fast reverse recovery time.

The main important features of this converter electronic circuit project , based on the NCL30100 compact switching regulator controller are : input voltage: Vin 115 Vac , nominal LED current: 700 mA (rms) , LED ripple: 120 mA (peak to peak) , VLED: 3.2 V , freewheel diode Vf: 0.5 V, target switching frequency: 50 kHz , dimming using PWM signal 1 kHz with duty cycle 0 – 99%  

Source By: W3Circuits