Analog Devices LTC7899

Description

The LTC®7899 is a high performance DC/DC negative to positive switching regulator controller that drives all N-channel synchronous MOSFET stages and can operate from input voltages up to 135V. The positive output voltage can easily be programmed with only two resistors by using the integrated feedback level shifter. The LTC7899 can alternatively be configured as a step-up (Boost) operation with pass-through.The gate drive voltage for the LTC7899 can be programmed from 5V to 10V to allow the use of logic or standard-level MOSFETs to maximize efficiency.The low no-load quiescent current extends operating run time in battery-powered systems. OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The user can adjust the dead times of the LTC7899 with external resistors for margin or to tailor the application for higher efficiency and allow for high frequency operation.The LTC7899 additionally features spread spectrum operation, which significantly reduces the peak radiated and conducted noise on both the input and output supplies, making it easier to comply with electromagnetic interference (EMI) standards.

Features

Converts Negative Input to Positive Output Regulated with Respect to GroundWide |VIN |+VOUT Range: 4V to 135V (140V ABS MAX)Internal Feedback Level Shifter for Easy Output Voltage Programming with Two ResistorsAdjustable Gate Drive Level: 5V to 10V (OPTI-DRIVE, 14V ABS MAX)Adjustable Driver Voltage UVLOAdaptive or Resistor-Adjustable Dead TimesSplit-Output Gate Drivers for Adjustable Turn-On and Turn-Off Driver StrengthsSupports Positive Input to Positive Output Boost Up to 135V with Pass-ThroughOperation Down to 1V after Start-UpCLK Output for High Power PolyPhase OperationSpread Spectrum Frequency ModulationProgrammable Frequency (100kHz to 2.5MHz)Phase-Lockable Frequency (100kHz to 2.5MHz)28-Pin (4mm x 5mm) QFN Package

Typical applications

More information

• Datasheet
• IC product information