Overview

Features and Benefits

  • Single Controller Operates Two Output Stages Antiphase Reducing Required Input Capacitance and Power Supply Induced Noise
  • Two 5-Bit Desktop VID Codes:
    • LTC1709-8 For VRM8.4 (VOUT from 1.3V to 3.5V)
    • LTC1709-9 For VRM9.0 (VOUT from 1.1V to 1.85V)
  • Current Mode Control Ensures Best Current Sharing
  • True Remote Sensing Differential Amplifier
  • Power Good Output Indicator
  • OPTI-LOOP Compensation Minimizes COUT
  • Programmable Fixed Frequency: 150kHz to 300kHz
  • ±1% Output Voltage Accuracy
  • Wide VIN Range: 4V to 36V Operation
  • Adjustable Soft-Start Current Ramping
  • Internal Current Foldback and Short-Circuit Shutdown
  • Overvoltage Soft Latch Eliminates Nuisance Trips
  • Low Shutdown Current: 20µA
  • Available in 36-Lead Narrow SSOP Package

Product Details

The LTC1709-8/LTC1709-9 are 2-phase, VID programmable, synchronous step-down switching regulator controllers that drive two all N-channel external power MOSFET stages in a fixed frequency architecture. The 2-phase controller drives its two output stages out of phase at frequencies from 150kHz to 300kHz to minimize the RMS ripple currents in both input and output capacitors. The 2-phase technique effectively multiplies the fundamental frequency by two, improving transient response while operating each channel at an optimum frequency for efficiency. Thermal design is also simplified.

An internal differential amplifier provides true remote sensing of the regulated supply’s positive and negative output terminals as required for high current applications.

The RUN/SS pin provides soft-start and optional timed, short-circuit shutdown. Current foldback limits MOSFET dissipation during short-circuit conditions when the overcurrent latchoff is disabled. OPTI-LOOP compensation allows the transient response to be optimized for a wide range of output capacitors and ESR values. The LTC1709-8/LTC1709-9 implement two different VID tables compliant with VRM8.4 and VRM9.0 respectively.

Vout Range VRM
LTC1709 1.3V to 3.5V VRM8.4
LTC1709-7 0.925V to 2V Mobile
LTC1709-8 1.3V to 3.5V VRM8.4
LTC1709-85 1.05V to 1.825V VRM8.5
LTC1709-9 1.1V to 1.85V VRM9.0

Applications

  • Workstations
  • Internet Servers
  • Large Memory Arrays
  • DC Power Distribution Systems

Product Lifecycle icon-recommended 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.

Evaluation Kits (2)

Tools & Simulations

LTspice

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.

LTspice

Models for the following parts are available in LTspice:

LTC1709
LTC1709-7
LTC1709-8
LTC1709-85
LTC1709-9

Product Recommendations

LTC1709-9 Companion Parts

Recommended Related Parts

Design Resources

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.

PCN-PDN Information

Sample & Buy

Sample & Buy functionality exists in desktop site
Back
Check Inventory

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.


Price Table Help

 
Evaluation Boards Pricing displayed is based on 1-piece.
Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.