Low voltage, low dropout linear regulators

January 16, 2014 // By Graham Prophet
Exar claims it has the lowest-voltage single supply LDOs with 140mV dropout, half that of other available parts, with its XRP6274/75 2A/3A parts that operate down to 1.045V VIN and do not need external bias.

The two low-dropout (LDO) regulators support 2A and 3A loads from a single low voltage supply with a maximum dropout voltage of 140mV. They operate with industry-standard low voltage rails of 1.1V to 2.5V providing a single supply solution for point-of-load voltage regulation.

Exar achieves this ultra low dropout performance without requiring either an external bias voltage or an internal charge pump, which can often generate unwanted noise and affect system operation. The LDOs use a single supply and reduce board layout complexity by avoiding the need to route a secondary bias rail to the LDO. Start up is guaranteed from an input voltage as low as 1.045V, providing output voltages down to 0.6V with an accuracy of 0.5% using ceramic capacitors. Enable and power good functions allow for sequencing and control of these LDOs.

In 10-pin 3 x 3 mm DFN packages they cost from $3.20 and $3.60 (1000).

Exar; www.exar.com