.. switch between doubler and bridge configurations. For 115V-rms 20% line operation, the Reference terminal of the TL431 programmable shunt regulator has a voltage lower than its 2.5V internal reference (Figure 2). In this ...
.. Comparator U1b compares the value of the sawtooth-like waveform across C1 to a 4.49-V reference voltage provided by U3, a TL431 adjustable shunt regulator (Fig. 2). The output of U1b is connected to the gate of the N-channel MOSFET (T1), ...
.. the current across R 3 , turning off Q 2 . When the rectified line voltage is lower than 380V, the cathode current of the TL431 is approximately 0A. Thus, Q 2 turns on through R3, connecting bulk capacitor C and R LOAD to the full-wave ...
.. the need for feedback components, the power stage uses a constant current source design. This allows a shunt, such as the TL431 or even a simple zener clamp, to provide output voltage regulation. Dual comparators act as a low-cost dc-dc ...
.. to the output here. The voltage doubler feeds this voltage to the gate through resistor R1. Adjustable shunt regulator TL431 (IC2) is used here as an error amplifier, and it dynamically adjusts the gate voltage to maintain the ...