Features and Benefits
- Highest Efficiency Current Mode Controller
- No Sense Resistor Required
- 300mV Maximum Current Sense Voltage
- Stable High Current Operation
- Dual N-Channel MOSFET Synchronous Drive
- Wide VIN Range: 4V to 36V
- Wide VOUT Range: 1.19V to VIN
- ±1% 1.19V Reference
- Programmable Fixed Frequency with Injection Lock
- Very Low Drop Out Operation: 99% Duty Cycle
- Forced Continuous Mode Control Pin
- Optional Programmable Soft Start
- Pin Selectable Output Voltage
- Foldback Current Limit
- Output Overvoltage Protection
- Logic Controlled Micropower Shutdown: IQ < 30µA
- Available in 16-Lead Narrow SSOP and SO Packages
The LTC1775 is a synchronous step-down switching regulator controller that drives external N-channel power MOSFETs using few external components. Current mode control with MOSFET VDS sensing eliminates the need for a sense resistor and improves efficiency. Largely similar to the LTC1625, the LTC1775 has twice the maximum sense voltage for high current applications. The frequency of a nominal 150kHz internal oscillator can be synchronized to an external clock over a 1.5:1 frequency range.
Burst Mode™ operation at low load currents reduces switching losses and low dropout operation extends operating time in battery-powered systems. A forced continuous mode control pin can assist secondary winding regulation by disabling Burst Mode operation when the main output is lightly loaded.
Fault protection is provided by foldback current limiting and an output overvoltage comparator. An external capacitor attached to the RUN/SS pin provides soft start capability for supply sequencing. A wide supply range allows operation from 4V (4.3V for LTC1775I) to 36V at the input and 1.19V to VIN at the output.
- Notebook Computers
- Automotive Electronics
- Battery Chargers
- Distributed Power Systems
Product Lifecycle Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
Models for the following parts are available in LTspice:
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
Sample & Buy
The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.