ADP5051
Data Sheet
TABLE OF CONTENTS
Features .............................................................................................. 1
Supervisory Circuit .................................................................... 26
Applications....................................................................................... 1
I2C Interface .................................................................................... 29
General Description ......................................................................... 1
SDA and SCL Pins...................................................................... 29
Typical Application Circuit ............................................................. 1
I2C Addresses .............................................................................. 29
Revision History ............................................................................... 3
Self-Clear Register Bits .............................................................. 29
Functional Block Diagram .............................................................. 4
I2C Interface Timing Diagrams ................................................ 30
Specifications..................................................................................... 5
Applications Information .............................................................. 31
Buck Regulator Specifications .................................................... 6
ADIsimPower Design Tool ....................................................... 31
Supervisory Specifications .......................................................... 8
Programming the Adjustable Output Voltage........................ 31
I2C Interface Timing Specifications ........................................... 9
Voltage Conversion Limitations............................................... 31
Absolute Maximum Ratings.......................................................... 10
Current-Limit Setting ................................................................ 31
Thermal Resistance .................................................................... 10
Soft Start Setting ......................................................................... 32
ESD Caution................................................................................ 10
Inductor Selection ...................................................................... 32
Pin Configuration and Function Descriptions........................... 11
Output Capacitor Selection....................................................... 32
Typical Performance Characteristics ........................................... 13
Input Capacitor Selection.......................................................... 33
Theory of Operation ...................................................................... 19
Low-Side Power Device Selection............................................ 33
Buck Regulator Operational Modes......................................... 19
Programming the UVLO Input................................................ 33
Adjustable and Fixed Output Voltages .................................... 19
Compensation Components Design ....................................... 34
Dynamic Voltage Scaling (DVS) .............................................. 20
Power Dissipation....................................................................... 34
Internal Regulators (VREG and VDD) ................................... 20
Junction Temperature ................................................................ 35
Separate Supply Applications.................................................... 20
Design Example .............................................................................. 36
Low-Side Device Selection ........................................................ 20
Setting the Switching Frequency .............................................. 36
Bootstrap Circuitry .................................................................... 20
Setting the Output Voltage........................................................ 36
Active Output Discharge Switch .............................................. 21
Setting the Current Limit .......................................................... 36
Precision Enabling...................................................................... 21
Selecting the Inductor................................................................ 36
Oscillator ..................................................................................... 21
Selecting the Output Capacitor ................................................ 36
Synchronization Input/Output ................................................. 22
Selecting the Low-Side MOSFET............................................. 37
Soft Start ...................................................................................... 22
Designing the Compensation Network................................... 37
Parallel Operation....................................................................... 23
Selecting the Soft Start Time..................................................... 37
Startup with Precharged Output .............................................. 23
Selecting the Input Capacitor ................................................... 37
Current-Limit Protection .......................................................... 23
Recommended External Components .................................... 37
Frequency Foldback ................................................................... 24
Circuit Board Layout Recommendations ................................... 39
Hiccup Protection ...................................................................... 24
Typical Application Circuits ......................................................... 40
Latch-Off Protection .................................................................. 24
Register Map ................................................................................... 43
Undervoltage Lockout (UVLO) ............................................... 25
Detailed Register Descriptions ..................................................... 44
Power-Good Function ............................................................... 25
Register 1: PCTRL (Channel Enable Control),
Interrupt Function...................................................................... 25
Thermal Shutdown..................................................................... 26
Overheat Detection .................................................................... 26
Low Input Voltage Detection .................................................... 26
Address 0x01 ............................................................................... 44
Register 2: VID1 (VID Setting for Channel 1),
Address 0x02 ............................................................................... 44
Register 3: VID23 (VID Setting for Channel 2 and Channel 3),
Address 0x03 ............................................................................... 45
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