Description
The SC4431 is a four terminal device for regulating an isolated power supply with output voltages down to 1.5V.
It is intended to be used as a replacement for three terminal shunt regulators such as SC431L where the output voltage is too low for the device to function in conjunction with an opto-isolator. SC4431 achieves this by having seperate supply and output pins, allowing the output to sink current at voltages as low as 0.1V, while the supply pin still has sufficient voltage for the device to function. In this way, allowing for a 1.4V drop through an opto-isolator diode, regulation down to 1.5V out can be achieved.

Features
◆ Open Collector output drives Optoisolator with as little as 1.5V input voltage
◆ Trimmed bandgap design - initial accuracies to + 0.5%
◆ 40mA drive capability
◆ Regulates output as low as 50mV
◆ Wide supply voltage range - 1.5V to 15V
◆ Low supply current - typically 110µA
◆ Full industrial temperature range
◆ SOT-23 5 lead package

Applications
◆ Telecom Power Supplies
◆ Opto driver for very low output voltage (1.5V) isolated power supplies
◆ Battery operated applications
◆ Point of use power supplies