Analog Devices LTC3895

Description

The LTC®3895 is a high performance step-down switchingregulator DC/DC controller that drives an all N-channelsynchronous power MOSFET stage that can operate frominput voltages up to 140V. A constant frequency currentmode architecture allows a phase-lockable frequency of upto 850kHz.The gate drive voltage can be programmed from 5V to 10Vto allow the use of logic or standard-level FETs to maximizeefficiency. An integrated switch in the top gate drivereliminates the need for an external bootstrap diode. Aninternal charge pump allows for 100% duty cycle operation.The low 40μA no-load quiescent current extends operatingrun time in battery-powered systems. OPTI-LOOP® compensationallows the transient response to be optimizedover a wide range of output capacitance and ESR values.The LTC3895 features a precision 0.8V reference andpower good output indicator. The output voltage can beprogrammed between 0.8V to 60V using external resistorsor pin-programmed for a fixed 5V or 3.3V.

Features

Wide VIN Range: 4V to 140V (150V Abs Max)

Wide Output Voltage Range: 0.8V to 60V

Adjustable Gate Drive Level: 5V to 10V (OPTI-DRIVE)

Low Operating IQ: 40μA (Shutdown = 10μA)

100% Duty Cycle Operation

No External Bootstrap Diode Required

Selectable Gate Drive UVLO Thresholds

On-board LDO or External NMOS LDO for DRVCC

EXTVCC LDO Powers Drivers from VOUT

Phase-Lockable Frequency (75kHz to 850kHz)

Programmable Fixed Frequency (50kHz to 900kHz)

Selectable Continuous, Pulse Skipping or Low RippleBurst Mode® Operation at Light Loads

Adjustable Burst Clamp and Current Limit

Adjustable or Fixed (5V/3.3V) Output Voltage

Power Good Output Voltage Monitor

Programmable Input Overvoltage Lockout

38-Lead TSSOP High Voltage Package

Typical applications

• Telecommunications Power Systems
• Automotive and Industrial Power Systems
• High Voltage Battery Operated Systems

More information

• Datasheet
• IC product information