Datasheet AS1371 400mA, Low Input Voltage, Low Quiescent Current LDO 1 General Description 2 Key Features Ultra-Low Dropout Voltage: 20mV 100mA load The AS1371 low input voltage, positive voltage regulator is designed to deliver up to 400mA while consuming typically only 15A of Operating Input Voltage Range: 1.2V to 3.6V quiescent current. The device operates from input voltages of 1.2V Output Voltages: 0.6V to 3.3V in 50mV steps to 3.6V, and is available in fixed output voltages between 0.6V and 3.3V (programmable in 50mV steps). Max. Output Current: 400mA Operation at the full 400mA load current is dependent upon the Output Voltage Accuracy: 1% maximum power dissipation available from package and Low Shutdown Current: 10nA environment. Low Quiescent Current: 50A max load The low input voltage and ultra-low dropout voltage (20mV 100mA load and 80mV 400mA load) supports single primary cell Integrated Overtemperature/Overcurrent Protection operation in small applications, when operated with minimum input- Under-Voltage Lockout Feature to-output voltage differentials. In addition, the regulator provides a Chip Enable Input power management life extension by operating from pre-existing 1.8V and 2.5V outputs to provide low output voltages for new Power-OK and Low Battery Detection generation portable processor cores. Sense Input Option The device features stable output voltage with ceramic capacitors Minimal External Components Required down to a value of 1F, strict output voltage regulation tolerances (1%), and good line- and load-regulation. Operating Temperature Range: -40C to +85C The AS1371 is available in a 6-pin 2x2 TDFN package and is 6-pin 2x2 TDFN Package qualified for -40C to +85C operation. 3 Applications The devices are ideal for powering cordless and mobile phones, MP3 players, CD and DVD players, PDAs, hand-held computers, digital cameras, and any other hand-held and/or battery-powered Figure 1. AS1371 - Typical Application Diagram device. Input Output 1.2V to 3.6V 0.6V to 3.3V IN OUT C IN C OUT 1F 1F AS1371 100k ON EN POK OFF GND SENSE www.austriamicrosystems.com/LDOs/AS1371 Revision 1.6 1 - 17AS1371 Datasheet - Pin Assignments 4 Pin Assignments Figure 2. Pin Assignments (Top View) IN 1 6 OUT POK SENSE 2 AS1371 5 Exposed Pad EN 3 4 GND 4.1 Pin Descriptions Table 1. Pin Descriptions Pin Number Pin Name Description LDO Input. Input voltage range: 1.2V to 3.6V. Bypass with 1F to GND. 1IN Power-OK Output. Active-low, open-drain output indicates an out-of-regulation condition. 2POK Connect a 100k pull-up resistor to pin OUT for logic levels. Leave this pin unconnected if the Power-OK feature is not used. Active-High Enable Input. A logic low reduces the supply current to < 1A. 3 EN Connect to pin IN for normal operation. Ground. This pin also functions as a heat sink. Solder it to a large pad or to the circuit-board 4GND ground plane to maximize power dissipation. Sense Input. Represents the input for the Power-OK behavior. If connected to GND the POK 5 SENSE output is related to OUT. LDO Output. Bypass with 1F to GND. 6OUT Exposed Pad. This pin also functions as a heat sink. Solder it to a large pad or to the circuit- Exposed Pad GND board ground plane to maximize power dissipation. Internally it is connected GND. www.austriamicrosystems.com/LDOs/AS1371 Revision 1.6 2 - 17