ADP1853 Datasheet, PDF (2/28 Pages) Analog Devices – Synchronous, Step-Down DC-to-DC Controller

ADP1853
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications....................................................................................... 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications..................................................................................... 3
Absolute Maximum Ratings............................................................ 6
ESD Caution.................................................................................. 6
Simplified Block Diagram ............................................................... 7
Pin Configuration and Function Descriptions............................. 8
Typical Performance Characteristics ........................................... 10
Theory of Operation ...................................................................... 12
Control Architecture .................................................................. 12
Oscillator Frequency .................................................................. 12
Synchronization .......................................................................... 13
PWM or Pulse Skip Mode of Operation ................................. 13
CLKOUT Signal.......................................................................... 13
Synchronous Rectifier and Dead Time ................................... 14
Input Undervoltage Lockout..................................................... 14
Internal Linear Regulator .......................................................... 14
Overvolage Protection ............................................................... 14
Power Good................................................................................. 14
Short-Circuit and Current-Limit Protection .......................... 15
Enable/Disable Control ............................................................. 15
REVISION HISTORY
5/12—Revision 0: Initial Version
Data Sheet
Thermal Overload Protection .................................................. 16
Interleaved Dual-Phase Operation .......................................... 16
Applications Information .............................................................. 17
ADIsimPower Design Tool ....................................................... 17
Setting the Output Voltage........................................................ 17
Soft Start ...................................................................................... 17
Setting the Current Limit .......................................................... 17
Accurate Current-Limit Sensing .............................................. 17
Input Capacitor Selection.......................................................... 17
VIN Pin Filter ............................................................................. 18
Boost Capacitor Selection ......................................................... 18
Inductor Selection ...................................................................... 18
Output Capacitor Selection....................................................... 18
MOSFET Selection..................................................................... 19
Loop Compensation—Voltage Mode ...................................... 20
Loop Compensation—Current Mode ..................................... 21
Switching Noise and Overshoot Reduction............................ 23
Voltage Tracking ......................................................................... 23
PCB Layout Guidlines ............................................................... 24
Typical Operating Circuits ............................................................ 25
Outline Dimensions ....................................................................... 27
Ordering Guide .......................................................................... 27
Rev. 0 | Page 2 of 28