FEATURES

 Wide VIN Range: 4V to 135V (140V ABS MAX)

 Wide Output Voltage Range: 0.8V ≤ VOUT ≤ 135V

(140V ABS MAX)

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

15V ABS MAX)

 Adjustable Driver Voltage UVLO

 Adaptive or Resistor Adjustable Dead Times

 Split-Output Gate Drivers for Adjustable Turn-On

and Turn-Off Driver Strengths

 100% Duty Cycle Operation

 Low Operating IQ: 5μA (48VIN to 3.3VOUT)

 Spread Spectrum Frequency Modulation

 Programmable Frequency (100kHz to 2.5MHz)

 Synchronizable Frequency (100kHz to 2.5MHz)

 28-Pin (4mm x 5mm) QFN Package

APPLICATIONS

 Industrial Power Systems

 Military/Avionics

 Telecommunications Power Systems

GENERAL DESCRIPTION

The LTC®7897 is a high performance, 100% duty cycle

capable, synchronous step-down, DC/DC switching

regulator controller that drives all N-channel

synchronous silicon metal oxide field effect transistor

(MOSFET) power stages. Synchronous rectification

increases efficiency, reduces power loss, and simplifies

the application design by reducing thermal

requirements.

The wide input and output voltage ranges of the

LTC7897 enable not only high step-down ratios but also

a wide range of positive to negative voltage conversion.

The gate drivers of the LTC7897 provide robustness with

a 15V ABS MAX rating and flexibility with adjustable

drive levels and dead times to optimize applications.

The gate drive voltage of the LTC7897 can optionally be

adjusted from 5V to 10V to allow use of logic-level or

standard threshold MOSFETs. The dead times of the

LTC7897 can be optimized with external resistors for

margin or to tailor the application for higher efficiency

and allow for high frequency operation.