LTM4641
TABLE OF CONTENTS
Features .................................................... 1
Applications ................................................ 1
Typical Application ........................................ 1
Description.................................................. 1
Absolute ꢁaꢂiꢃuꢃ Ratings.............................. 3
Order Inforꢃation.......................................... 3
Pin Configuration .......................................... 3
Electrical Characteristics................................. 4
Typical Perforꢃance Characteristics ................... 8
Pin Functions..............................................10
Siꢃplified Block Diagraꢃ ...............................15
Decoupling Requireꢃents...............................15
Operation...................................................16
Introduction............................................................ 16
Motivation............................................................... 16
Power µModule Regulator Reliability...................... 16
Overview................................................................. 16
Applications Inforꢃation—Power Supply Features .17
Overcurrent Foldback Protection ............................32
Power Good Indicator and Latching Output
Overvoltage Protection...........................................32
Power-Interrupt MOSFET (MSP), CROWBAR Pin and
Output CROWBAR MOSFET (MCB) ........................33
Fast Output Overvoltage Comparator Threshold.....34
Applications Inforꢃation—EꢁI Perforꢃance ........35
The Switching Node: SW Pin..................................35
Applications Inforꢃation—ꢁultiꢃodule Parallel
Operation...................................................36
Applications Inforꢃation—Therꢃal Considerations
and Output Current Derating ............................38
Thermal Considerations and Output Current
Derating..................................................................38
Applications Inforꢃation—Output Capacitance
Table........................................................45
Applications Inforꢃation—Safety and Layout
Guidance ...................................................46
Safety Considerations.............................................46
Layout Checklist/Example ......................................46
Typical Applications......................................48
Appendices ................................................55
Appendix A. Functional Block Diagram and Features
Quick Reference Guide............................................55
Appendix B. Start-Up/Shutdown State Diagram .....56
Appendix C. Switching Frequency Considerations and
Power (V ) and Bias (V ) Input Pins................. 17
INH
INL
Switching Frequency (On Time) Selection and
Voltage Dropout Criteria (Achievable V -to-V
IN
OUT
Step-Down Ratios).................................................. 18
Setting the Output Voltage; the Differential Remote
Sense Amplifier ......................................................21
Input Capacitors .....................................................23
Output Capacitors and Loop Stability/Loop
Compensation.........................................................23
Pulse-Skipping Mode vs Forced Continuous Mode 24
Soft-Start, Rail-Tracking and Start-Up Into
Usage of R
........................................................57
fSET
Appendix D. Remote Sensing in Harsh
Environments..........................................................58
Appendix E. Inspiration For Pulse-Skipping Mode
Operation................................................................59
Appendix F. Adjusting the Fast Output Overvoltage
Comparator Threshold............................................59
Package Description .....................................62
Package Photo ............................................62
Package Description .....................................63
Typical Application .......................................64
Related Parts..............................................64
Pre-Bias..................................................................24
INTV and DRV .................................................27
CC
CC
1V ......................................................................28
REF
TEMP, OTBH and Overtemperature Protection........28
Applications Inforꢃation—Input Protection
Features....................................................29
Input Monitoring Pins: UVLO, IOVRETRY, OVLO ....29
Start-Up/Shutdown and Run Enable; Power-On Reset
and Timeout Delay Time .........................................31
Applications Inforꢃation—Load Protection
Features....................................................32
4641f
2
Linear [ Linear ]
