LT8616EFE#PBF

Features
LT8616EFE#PBF Dual 42V Synchronous Monolithic Step-Down Regulator with 6.5�A Quiescent Current Description

The is a high efficiency, high speed, dual synchronous monolithic step-down switching regulator that consumes only 6.5�A of quiescent current with both channels enabled. Both channels contain all switches and necessary circuitry to minimize the need for external components. Low ripple Burst Mode operation enables high efficiency down to very low output currents while minimizing output ripple. A SYNC pin allows synchronization to an external clock. Internal compensation with peak current mode topology allows the use of small inductors and results in fast transient response and good loop stability. The enable pins have accurate 1V thresholds and can be used to program undervoltage lockout. Capacitors on the TR/SS pins programs the output voltage ramp rate during startup while the PG pins signal when each output is within 10% of the programmed output voltage. The LT8616EFE#PBF is available in a TSSOP package for high reliability.

L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

Wide Input Voltage Range: 42V 2.5A and 1.5A Buck Regulators with Separate Inputs Fast Minimum Switch On-Time: 35ns Ultralow Quiescent Current Burst Mode� Operation: 6.5�A I Regulating Q IN OUT and 3.3VOUT n Output Ripple 15mV n180� Out of Phase Switching n Adjustable and Synchronizable: 3MHz n Accurate 1V Enable Pin Thresholds n Internal Compensation n Output Soft-Start and Tracking n TSSOP Package: Output Stays at or Below Regulation Voltage During Adjacent Pin Short or When a Pin Is Left Floating n Thermally Enhanced 28-Lead TSSOP Package

Applications
Automotive and Industrial Supplies n General Purpose Step-Down

BIAS...........................................................................30V BST1 Above SW1, BST2 Above TR/SS2......................................................4V SYNC/MODE................................................................6V Operating Junction Temperature Range (Note to 150�C Storage Temperature Range................... to 150�C

FE PACKAGE 28-LEAD PLASTIC TSSOP TJMAX = 10�C/W EXPOSED PAD (PIN 29) IS GND, MUST BE SOLDERED TO PCB

LEAD FREE FINISH LT8616IFE#PBF LT8616HFE#PBF TAPE AND REEL LT8616IFE#TRPBF LT8616HFE#TRPBF PART MARKING* LT8616FE PACKAGE DESCRIPTION 28-Lead Plastic TSSOP 28-Lead Plastic TSSOP 28-Lead Plastic TSSOP TEMPERATURE RANGE to 150�C

Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on nonstandard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/

The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are = 25�C.

PARAMETER Common Quiescent Current = 0V, Current from VIN1

= 2V, SYNC = 0V (Burst Mode), Not Switching, Current from = 2V, SYNC = 3V (Pulse-Skipping Mode), Not Switching, Current from BIAS VIN1 FB Voltage FB Voltage Line Regulation FB Pin Input Current EN/UV Pin Threshold EN/UV Pin Hysteresis EN/UV Pin Current PG Upper Threshold from VFB PG Lower Threshold from VFB PG Hysteresis PG Leakage PG Pull-Down Resistance TR/SS Source Current TR/SS Pull-Down Resistance BIAS Pin Current Consumption Oscillator Frequency TR/SS = 0.5A, fSW = 221k SYNC Falling SYNC Rising SYNC = 0.1V EN/UV 2V FB Rising FB Falling VIN = 6V, Load = 0.5A

SYNC Threshold SYNC Pin Current Channel 1 Minimum VIN1 Voltage Supply Current in Regulation SW1 Minimum On-Time SW1 Top NMOS On-Resistance SW1 Peak Current Limit SW1 Bottom NMOS On-Resistance SW1 Valley Current Limit SW1 Leakage Current

VIN = 3.3V, Load = 100�A VIN = 3.3V Load = 1mA Load = 0.25A, Pulse-Skipping Mode (Note 3)

Feature

Applications