500mA, Low Noise, LDO Micropower Regulators

The LT1763 series are micropower, low noise, low dropout regulators. The devices are capable of supplying 500mA of output current with a dropout voltage of 300mV. Designed for use in battery-powered systems, the low 30μA quiescent current makes them an ideal choice. Quiescent current is well controlled; it does not rise in dropout as it does with many other regulators.

A key feature of the LT1763 regulators is low output noise. With the addition of an external 0.01μF bypass capacitor, output noise drops to 20μVRMS over a 10Hz to 100kHz bandwidth. The LT1763 regulators are stable with output capacitors as low as 3.3μF. Small ceramic capacitors can be used without the series resistance required by other regulators.

Internal protection circuitry includes reverse battery protection, current limiting, thermal limiting and reverse current protection. The parts come in fixed output voltages of 1.5V, 1.8V, 2.5V, 3V, 3.3V and 5V, and as an adjustable device with a 1.22V reference voltage. The LT1763 regulators are available in 8-lead SO and 12-lead, low profile (4mm × 3mm × 0.75mm) DFN packages.

Applications

* Cellular Phones

* Battery-Powered Systems

* Noise-Sensitive Instrumentation Systems

* Low Noise: 20μVRMS (10Hz to 100kHz)

* Output Current: 500mA

* Low Quiescent Current: 30μA

* Wide Input Voltage Range: 1.8V to 20V

* Low Dropout Voltage: 300mV

* Very Low Shutdown Current: < 1μA

* No Protection Diodes Needed

* Fixed Output Voltages: 1.5V, 1.8V, 2.5V, 3V, 3.3V, 5V

* Adjustable Output from 1.22V to 20V

* Stable with 3.3μF Output Capacitor

* Stable with Aluminum, Tantalum or Ceramic Capacitors

* Reverse Battery Protection

* No Reverse Current

* Overcurrent and Overtemperature Protected

* 8-Lead SO and 12-Lead (4mm × 3mm) DFN Packages