AP1603WG-7

AP1603 STEP-UP DC-DC CONVERTER Description Pin Assignments The AP1603 is a high efficiency step-up DC-DC converter for applications using as few as a single NiMH or Li-Ion battery cells. ( Top View ) Only four external components are required to deliver a fixed output voltage of 3.3V. The AP1603 starts up from less than 0.9V input with 1 FB 6 SHDN 1mA load. Pulse Frequency Modulation scheme brings optimized performance for applications with light output loading and low input voltages. The output ripple and noise are lower compared with the AP1603 2 5 OUT GND circuits operating in PSM mode. The PFM control circuit operating in 150kHz (max.) switching rate 74 LX REF 3 results in smaller passive components. The space saving SOT26 packages make the AP1603 an ideal choice of DC-DC converter for space conscious applications, like pagers, electronic cameras, and SOT26 wireless microphones. Features Applications A Guaranteed Start-Up from less than 0.9 V Pagers High Efficiency Cameras Low Quiescent Current Wireless Microphones Less Number of External Components needed Pocket Organizers Low Ripple and Low Noise Battery Backup Suppliers Space Saving Lead Free Package: SOT26 Portable Instruments Available in Green molding Totally Lead-Free & Fully RoHS Compliant (Notes 1 & 2) Halogen and Antimony Free. Green Device (Note 3) Notes: 1. No purposely added lead. Fully EU Directive 2002/95/EC (RoHS) & 2011/65/EU (RoHS 2) compliant. 2. See + + + - + - + + - AP1603 Typical Applications Circuit (cont.) (2) V = 3.3V OUT 1.1V to 3.6V 22uH V IN + 47uF ON OFF LX SHDN Fixed Output OUT + ( 3.3V ) 47uF REF GND FB 0.1uF (3) V = ADJ OUT 22uH 1.1V to 5.5V V IN + 47uF ON LX OFF SHDN OUT Output + REF 47uF R2 GND FB 0.1uF R1 R2 V = V (1+ ) OUT REF R1 Pin Descriptions Pin Name Function FB Feedback. GND Ground. REF 1.2V Reference Voltage. Bypass with a 0.1 F capacitor. LX N-Channel and P-Channel Power MOSFET Drain. OUT Power Output. OUT provides bootstrap power to the IC. Shutdown Input. Drive high (>80% of V ) for operating mode. Drive low (<20% of V ) for OUT OUT SHDN shutdown mode. Connect to OUT for normal operation. Functional Block Diagram V OUT 0.1uF Zero Minimum Crossing SHDN Off-Time 47uF EN Amplifier One-Shot TRIG Q One-Shot P V LX IN 22uH 47uF F/F N S Q R Maximum On-Time One-Shot Current-Limit FB connects to Vcc or GND Amplifier TRIG Q GND One-Shot Error Amplifier FB connects to FB external feedback resistors 0.1uF 2 of 8 February 2014 AP1603 Diodes Incorporated www.diodes.com Document number: DS31131 Rev. 4 - 2 + -