Datasheet LTC3035 (Analog Devices)

LTC3035 300mA VLDO Linear Regulator with Charge Pump Bias Generator
U FEATURES DESCRIPTIO
■
Wide Input Voltage Range: 1.7V to 5.5V
The LTC®3035 is a micropower, VLDO™ (very low drop- ■
Wide Adjustable Output Voltage Range:
out) linear regulator which operates from input voltages as
0.4V to 3.6V
low as 1.7V. The device is capable of supplying 300mA of ■
Built-In Charge Pump Generates High Side Bias
output current with a typical dropout voltage of only ■
Very Low Dropout: 45mV at 300mA
45mV. To allow operation at low input voltages the LTC3035 ■ ±
2% Voltage Accuracy Over Temperature,
includes a charge pump generator that provides the nec-
Supply, Load
essary bias voltage for the internal LDO circuitry. Output ■ Fast Transient Recovery current comes directly from the input supply for high ■ Low Operating Current: IIN = 100µA Typ efficiency regulation. The charge pump bias generator ■ Low Shutdown Current: IIN = 1µA Typ requires only a 0.1µF flying capacitor and a 1µF bypass ■ Stable with Ceramic Capacitor Down to 1µF capacitor for operation. The low 0.4V internal reference ■ Output Current Limit voltage allows the LTC3035 to be programmed to much ■ Thermal Overload Protected lower output voltages than commonly available in LDOs. ■ Reverse Output Current Protected The output voltage is programmed via two tiny SMD ■ Available in 8-Lead (3mm × 2mm) DFN Package resistors. The LTC3035’s low quiescent current makes it
U
an ideal choice for use in battery-powered systems.
APPLICATIO S
Other features include high output voltage accuracy, ex- ■ Li-Ion to 3.3V Low Dropout Supplies cellent transient response, stability with ultralow ESR ■ 2 × AA to 1.8V Low Dropout Supplies ceramic capacitors as small as 1µF, short-circuit and ■ Low Power Handheld Devices thermal overload protection, output current limiting and ■ Low Voltage Logic Supplies reverse output current protection. The LTC3035 is avail- ■ DSP Power Supplies able in a tiny, low profile (3mm × 2mm × 0.75mm) 8-lead ■ Cellular Phones DFN package. ■ Portable Electronic Equipment , LTC and LT are registered trademarks of Linear Technology Corporation. ■ Handheld Medical Instruments VLDO is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ■ Post Regulator for Switching Supply Noise Rejection Protected by U.S. Patents, including 6411531, others pending.
U TYPICAL APPLICATIO Dropout Voltage vs Load Current 3.3V Output Voltage from Li-Ion Battery
70 TA = 25°C 0.1µF 60 50 CP CM BIAS BIAS 40 GENERATOR IN CBIAS 1µF 30 Li-Ion 1µF 0.4V + BATTERY VOUT 20 3.4V TO 4.2V OUT – DROPOUT VOLTAGE (mV) 3.3V COUT 300mA LTC3035 294k 10 1µF ADJ 0 OFF ON SHDN GND 40.2k 0 50 100 150 200 250 300 I 3035 TA01a OUT (mA) 3035 TA01b 3035f 1