Datasheet ADP2105, ADP2106, ADP2107 (Analog Devices) - 4

ADP2105/ADP2106/ADP2107 Data Sheet FUNCTIONAL BLOCK DIAGRAM COMP 5 14 IN 9 PWIN2 SOFT REFERENCE SS 6 START 0.8V CURRENT SENSE AMPLIFIER 13 PWIN1 FB 16 FB 16 GM ERROR AMP CURRENT PWM/ LIMIT AGND 7 PFM CONTROL FOR PRESET VOLTAGE DRIVER GND 2 OPTIONS ONLY AND 10 LX1 ANTI- GND 3 SHOOT THROUGH 12 LX2 SLOPE GND 4 COMPENSATION NC 8 GND 15 OSCILLATOR ZERO CROSS COMPARATOR 11 THERMAL PGND EN 1 SHUTDOWN
7 03 9- 07 06 Figure 3. Rev. E | Page 4 of 36 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION TYPICAL OPERATING CIRCUIT REVISION HISTORY FUNCTIONAL BLOCK DIAGRAM SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE BOUNDARY CONDITION ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION CONTROL SCHEME PWM MODE OPERATION PFM MODE OPERATION PULSE-SKIPPING THRESHOLD 100% DUTY CYCLE OPERATION (LDO MODE) DESIGN FEATURES Enable/Shutdown Synchronous Rectification Current Limit Short-Circuit Protection Undervoltage Lockout (UVLO) Thermal Protection Soft Start APPLICATIONS INFORMATION ADIsimPower DESIGN TOOL EXTERNAL COMPONENT SELECTION SETTING THE OUTPUT VOLTAGE INDUCTOR SELECTION OUTPUT CAPACITOR SELECTION INPUT CAPACITOR SELECTION INPUT FILTER SOFT START PERIOD LOOP COMPENSATION BODE PLOTS LOAD TRANSIENT RESPONSE EFFICIENCY CONSIDERATIONS Power Switch Conduction Losses Inductor Losses Switching Losses Transition Losses THERMAL CONSIDERATIONS DESIGN EXAMPLE EXTERNAL COMPONENT RECOMMENDATIONS CIRCUIT BOARD LAYOUT RECOMMENDATIONS EVALUATION BOARD EVALUATION BOARD SCHEMATIC FOR ADP2107 (1.8 V) RECOMMENDED PCB LAYOUT (EVALUATION BOARD LAYOUT) APPLICATION CIRCUITS OUTLINE DIMENSIONS ORDERING GUIDE