AS1329A

AS1329 1 General Description The AS1329A, AS1329B and the AS1329C are synchronous, fixed frequency, very high-efficiency DC-DC boost converters capable of supplying 3.3V at 160mA from a single AA-supply. Compact size and minimum external parts requirements make these devices perfect for modern portable devices. High-speed switching frequency (1.2MHz) and internally compensated PWM current mode design provide highlyreliable DC-DC conversion, especially when driving white LEDs. The converters are available as the standard products listed in Table 1. Table 1. Standard Products Model AS1329A Light Load Switching Medium Load Automatic Powersave Operation ! ! ! ! ! Product Brief L o w Vo l ta g e , M i c r o p o w e r, D C - D C St e p - U p C o n v e r t e r s 2 Key Features ! ! ! ! ! ! ! ! 95% Efficiency Single-Cell Operation Delivers 160mA @ 3.3V (from Single AA Cell) Delivers 220mA @ 5.0V (from Two AA Cells) Delivers 570mA @ 3.3V (from Two AA Cells) Low Start-Up Voltage: 0.85V High-Speed Fixed-Frequency: 1.2MHz Internal PMOS Synchronous Rectifier Automatic Powersave Operation (AS1329A&B) Continuous Switching at Light Loads (AS1329C) Anti-Ringing Control Minimizes EMI Logic Controlled Shutdown (< 1µA) Output Range: 2.5 to 5.0V 6-pin TSOT-23 Package AS1329B Light Load Automatic Powersave Operation AS1329C Continuous Switching The devices contain two internal MOSFET switches: one NMOS switch and one PMOS synchronous rectifier. Anti-ringing control circuitry reduces EMI by damping the inductor in discontinuous mode, and the devices exhibit extremely low quiescent current (< 1µA) in shutdown. In shutdown mode the battery is connected directly to the output enabling the supply of real-time-clocks. The AS1329 is available in a 6-pin TSOT-23 package. ! 3 Applications The AS1329 is ideal for low-power applications where ultra-small size is critical as in medical diagnostic equipment, hand-held instruments, pagers, digital cameras, remote wireless transmitters, MP3 players, LCD bias supplies, cordless phones, GPS receivers, and PC cards. Figure 1. Typical Application Diagram – Single Cell to 3.3V Synchronous Boost Converter L1 4.7µH 1 AA Battery C1 10µF 6 SW 5 VOUT VIN AS1329 4 3 R1 1.02MΩ 1% FB C2 10µF VOUT 3.3V 160mA On Off SHDNN 2 GND R2 604kΩ 1% www.austriamicrosystems.com Revision 1.01 1-2 AS1329 Product Brief - Applications Copyrights Copyright © 1997-2007, austriamicrosystems AG, Schloss Premstaetten, 8141 Unterpremstaetten, Austria-Europe. Trademarks Registered ®. All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. All products and companies mentioned are trademarks or registered trademarks of their respective companies. Disclaimer Devices sold by austriamicrosystems AG are covered by the warranty and patent indemnification provisions appearing in its Term of Sale. austriamicrosystems AG makes no warranty, express, statutory, implied, or by description regarding the information set forth herein or regarding the freedom of the described devices from patent infringement. austriamicrosystems AG reserves the right to change specifications and prices at any time and without notice. Therefore, prior to designing this product into a system, it is necessary to check with austriamicrosystems AG for current information. This product is intended for use in normal commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or lifesustaining equipment are specifically not recommended without additional processing by austriamicrosystems AG for each application. For shipments of less than 100 parts the manufacturing flow might show deviations from the standard production flow, such as test flow or test location. The information furnished here by austriamicrosystems AG is believed to be correct and accurate. However, austriamicrosystems AG shall not be liable to recipient or any third party for any damages, including but not limited to personal injury, property damage, loss of profits, loss of use, interruption of business or indirect, special, incidental or consequential damages, of any kind, in connection with or arising out of the furnishing, performance or use of the technical data herein. No obligation or liability to recipient or any third party shall arise or flow out of austriamicrosystems AG rendering of technical or other services. Contact Information Headquarters austriamicrosystems AG A-8141 Schloss Premstaetten, Austria Tel: +43 (0) 3136 500 0 Fax: +43 (0) 3136 525 01 For Sales Offices, Distributors and Representatives, please visit: http://www.austriamicrosystems.com/contact www.austriamicrosystems.com Revision 1.01 2-2