LTC1625 - No RSENSE Current Mode Synchronous Step-Down Switching Regulator

Features

  • Highest Efficiency Current Mode Controller
  • No Sense Resistor Required
  • Stable High Current Operation
  • Dual N-Channel MOSFET Synchronous Drive
  • Wide VIN Range: 3.7V 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

Typical Application

LTC1625 Typical Application
LTC1625 Typical Application

Description

The LTC1625 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. 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 3.7V (3.9V for LTC1625I) to 36V at the input and 1.19V to VIN at the output.

Packaging

For complete and up to date package information and drawings, please refer to our packaging page

SSOP-16

LTC1625 Package Drawing

Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price (1-99) Price (1k)* RoHS Data
LTC1625CGN SSOP 16 C $5.80 $4.90 View
LTC1625CGN#PBF SSOP 16 C $5.80 $4.90 View
LTC1625CGN#TR SSOP 16 C $4.96 View
LTC1625CGN#TRPBF SSOP 16 C $4.96 View
LTC1625CS SO 16 C $5.45 $4.55 View
LTC1625CS#PBF SO 16 C $5.45 $4.55 View
LTC1625CS#TR SO 16 C $4.61 View
LTC1625CS#TRPBF SO 16 C $4.61 View
LTC1625IGN SSOP 16 I $7.02 $5.90 View
LTC1625IGN#PBF SSOP 16 I $7.02 $5.90 View
LTC1625IGN#TR SSOP 16 I $5.96 View
LTC1625IGN#TRPBF SSOP 16 I $5.96 View
LTC1625IS SO 16 I $6.75 $5.50 View
LTC1625IS#PBF SO 16 I $6.75 $5.50 View
LTC1625IS#TR SO 16 I $5.56 View
LTC1625IS#TRPBF SO 16 I $5.56 View
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* 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 Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC203A LTC1625CS | No Rsense CURRENT MODE CONTROLLER, 4.5V to 28Vin, 3.3V or 5V @ 4.5A Vout (thru-hole cap) $125.00
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Applications

  • Notebook and Palmtop Computers, PDAs
  • Cellular Telephones and Wireless Modems
  • Battery Chargers
  • Distributed Power

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LTC1625

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