The AME4311 is a low volatge version of the industry standard 431 shunt regulator. The AME4311 reference is set to 1.24 volts. The output voltage can be set to any value between 1.24V and 8V with two external resistors. (For factory set internal feedback resistors see the AME4312.) When used with an optocoupler these devices are ideal for isolated 3.3V switching supplies. Analog Microelectronics offers this part in a TO-92 package as well as the space saving SOT-23 and SOT-25 packages.