ADP5133Data SheetPIN CONFIGURATION AND FUNCTION DESCRIPTIONSBALL A1INDICATOR1234FB1AGND AGNDFB2AAGND MODEEN1EN2BVIN1 VOUT1 VOUT2 VIN2CPGND1 SW1SW2PGND2DTOP VIEW 02 (BALL SIDE DOWN) 0 1- Not to Scale 199 1 Figure 2. Pin Configuration Table 7. Pin Function Descriptions Pin No.MnemonicDescription A1 FB1 BUCK1 Feedback Input. For device models with an adjustable output voltage, connect this pin to the middle of the BUCK1 resistor divider. For device models with a fixed output voltage, leave this pin unconnected. A2 AGND Analog Ground. A3 AGND Analog Ground. A4 FB2 BUCK2 Feedback Input. For device models with an adjustable output voltage, connect this pin to the middle of the BUCK2 resistor divider. For device models with a fixed output voltage, leave this pin unconnected. B1 AGND Analog Ground. B2 MODE BUCK1/BUCK2 Operating Mode. If MODE is set high, the buck regulators operate in forced PWM mode. If MODE is set low, the switching regulators operate in auto PWM/PSM mode. B3 EN1 BUCK1 Enable. Active High. B4 EN2 BUCK2 Enable. Active High. C1 VIN1 BUCK1 Input Supply (2.3 V to 5.5 V) and UVLO Detection. Connect VIN1 to VIN2. C2 VOUT1 BUCK1 Output Voltage Sensing Input. C3 VOUT2 BUCK2 Output Voltage Sensing Input. C4 VIN2 BUCK2 Input Supply (2.3 V to 5.5 V). Connect VIN2 to VIN1. D1 PGND1 Dedicated Power Ground for BUCK1. D2 SW1 BUCK1 Switching Node. D3 SW2 BUCK2 Switching Node. D4 PGND2 Dedicated Power Ground for BUCK2. Rev. A | Page 6 of 24 Document Outline FEATURES APPLICATIONS GENERAL DESCRIPTION TYPICAL APPLICATION CIRCUIT TABLE OF CONTENTS REVISION HISTORY SPECIFICATIONS GENERAL SPECIFICATIONS BUCK1 AND BUCK2 SPECIFICATIONS INPUT AND OUTPUT CAPACITOR, RECOMMENDED SPECIFICATIONS ABSOLUTE MAXIMUM RATINGS THERMAL RESISTANCE ESD CAUTION PIN CONFIGURATION AND FUNCTION DESCRIPTIONS TYPICAL PERFORMANCE CHARACTERISTICS THEORY OF OPERATION POWER MANAGEMENT UNIT Thermal Protection Undervoltage Lockout Enable/Shutdown BUCK1 AND BUCK2 Control Scheme PWM Mode Auto PSM/PWM Operation PSM Current Threshold Oscillator/Phasing of Inductor Switching Short-Circuit Protection Soft Start Current Limit 100% Duty Operation Active Pull-Downs APPLICATIONS INFORMATION BUCK EXTERNAL COMPONENT SELECTION Feedback Resistors Inductor Output Capacitor Input Capacitor POWER DISSIPATION AND THERMAL CONSIDERATIONS BUCK REGULATOR POWER DISSIPATION JUNCTION TEMPERATURE PCB LAYOUT GUIDELINES TYPICAL APPLICATION SCHEMATICS OUTLINE DIMENSIONS ORDERING GUIDE