Datasheet ADP1621 (Analog Devices) - 3

Data Sheet ADP1621 SIMPLIFIED BLOCK DIAGRAM VREF 1.215V ERROR SOFT START AMPLIFIER (2048 CYCLES) gm PIN FB 5.5V COMP VOSC 1.4V SET OSC S FREQ GATE SLOPE R COMP GATE PWM DRIVER COMPARATOR + IN + UVLO CS SDSN n PGND 100kΩ 5.5V GND
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ADP1621
0 090- 06 Figure 3. ADP1621 Simplified Block Diagram Rev. D | Page 3 of 32 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION TYPICAL APPLICATION CIRCUIT TABLE OF CONTENTS REVISION HISTORY SIMPLIFIED BLOCK DIAGRAM SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION CONTROL LOOP CURRENT-SENSE CONFIGURATIONS CURRENT LIMIT UNDERVOLTAGE LOCKOUT SHUTDOWN SOFT START INTERNAL SHUNT REGULATORS SETTING THE OSCILLATOR FREQUENCY AND SYNCHRONIZATION FREQUENCY APPLICATION INFORMATION: BOOST CONVERTER ADIsimPower DESIGN TOOL DUTY CYCLE SETTING THE OUTPUT VOLTAGE INDUCTOR CURRENT RIPPLE INDUCTOR SELECTION INPUT CAPACITOR SELECTION OUTPUT CAPACITOR SELECTION DIODE SELECTION MOSFET SELECTION LOOP COMPENSATION SLOPE COMPENSATION CURRENT LIMIT LIGHT LOAD OPERATION Discontinuous Conduction Mode Pulse-Skipping Modulation RECOMMENDED COMPONENT MANUFACTURERS LAYOUT CONSIDERATIONS EFFICIENCY CONSIDERATIONS EXAMPLES OF APPLICATION CIRCUITS STANDARD BOOST CONVERTER—DESIGN EXAMPLE BOOTSTRAPPED BOOST CONVERTER Low Input and High Output Boost Converter High Input Voltage Boost Converter Circuit SEPIC CONVERTER CIRCUIT LOW VOLTAGE POWER-INPUT CIRCUIT LED DRIVER APPLICATION CIRCUITS RELATED DEVICES OUTLINE DIMENSIONS ORDERING GUIDE