LT3483/LT3483A APPLICATIONS INFORMATIONBoard Layout Considerations and area of all traces connected to the SW and D pins. As with all switching regulators, careful attention must In particular, it is desirable to minimize the trace length be given to the PCB board layout and component place- to and from the flying capacitor, since current in this ca- ment. Proper layout of the high frequency switching path pacitor switches directions within a cycle. Always use a is essential. The voltage signals of the SW and D pins ground plane under the switching regulator to minimize have sharp rising and falling edges. Minimize the length interplane coupling. Suggested Layout (DFN)Suggested Layout (SOT-23)for Inverting Charge Pumpfor Inverting Charge Pump + GND VOUT R1 CIN L1 C A OUT CFLY VIN SHDN 1 8 K 1 6 2 7 9 3 2 5 6 GND 4 5 3 4 COUT VIN CIN CFLY R1 L1 SHDN VOUT 3483 AI02 3483 AI01 TYPICAL APPLICATIONS3.6V to –22V DC/DC Converter3.6V to –22V Converter Efficiency and Power Loss C2 75 1000 L1 0.1µF D1 10µH VIN EFFICIENCY 3.6V RS 70 100 POWER LOSS (mW) SW 30Ω VOUT V –22V IN D 8mA C1 R1 LT3483 C3 65 10 4.7µF 5pF 2.2M 1µF POWER SHDN FB LOSS EFFICIENCY (%) GND 60 1 C1: TAIYO YUDEN LMK316BJ475MD 3483 TA02a C2: TAIYO YUDEN TMK107BJ104 (X5R) C3: TAIYO YUDEN TMK316BJ105MD 55 0.1 D1: PHILIPS PMEG3002AEB 0.1 1 10 L1: MURATA LQH2MCN100K02L LOAD CURRENT (mA) 3483 TA02b 3483fc 8 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration order information Electrical Characteristics Typical Performance Characteristics pin functions block diagram operation applications information typical applications Package Description Revision History Typical Application Related Parts