G5723 Global Mixed-mode Technology Inc. Synchronous Buck Converter with Low-Noise LDO Regulator Features Applications Buck Converter High Efficiency: Up to 95% Low Quiescent Current: Only 50µA During Operation Internal Soft Start Function 600mA Output Current 2.5V to 6V Input Voltage Range 1.2MHz Switching Frequency No Schottky Diode Required 100% Duty Cycle in Dropout Operation 0.6V Reference Allows Low Output Voltages <1µA Shutdown Current Current Mode Operation for Excellent Line and Load Transient Response General Description The G5723 consists of a synchronous step-down DC/DC converter and a low-noise LDO regulator. The DC/DC converter is operated on current mode architecture. Switching frequency is set at 1.2MHz allowing the use of small surface mount inductor and capacitor. The internal synchronous switches increase efficiency and eliminate the need for external Schottky diode. It is ideal for system powered by a 1-cell Li-ion battery. LDO Regulator Digital Still and Video Cameras MP3 Players Portable Instruments Ultra Low Output Noise 30µV (rms) Ultra Low 55µA No-Load Supply Current Ultra Low Dropout 70mV @ 50mA Load Guarantee 300mA Output Current Fixed Mode: No External Resistor Network Needed Max. Supply Current in Shutdown Mode < 1µA Stable with Low Cost Ceramic Capacitors Over Temperature Protected RoHS Compliant Ordering Information ORDER NUMBER MARKING VOLTAGE TEMP. RANGE PACKAGE (Green) G5723-18P71U G5723-30P71U G5723G G5723E 1.8V 3.0V -40°C to +85°C -40°C to +85°C MSOP-10 MSOP-10 G5723-33P71U G5723F 3.3V -40°C to +85°C MSOP-10 Note: P7: MSOP-10 1: Bonding Code U: Tape & Reel Pin Configuration Typical Application Circuit G5723 VIN 3.3~4.2V G5723 LX EN1 1 10 AGND 2 9 PGND FB1 3 8 IN1 AGND 4 7 OUT2 EN2 5 6 IN2 BATTERY IN1 CIN1 2.2µF 2.2µH LX CFB * (option) VOUT1 1.2V 600mA COUT1 10µF EN1 FB1 R1 R2 18K 18K IN2 CIN2 1µF MSOP-10 EN2 OUT2 AGND PGND VOUT2 COUT2 4.7µF R1 ) VOUT1 = 0.6V × (1+ R2 TEL: 886-3-5788833 http://www.gmt.com.tw Ver: 0.4 Aug 30, 2010 1