LT1949 - 600kHz, 1A Switch PWM DC/DC Converter

The LT1949 is a fixed frequency step-up DC/DC converter with a 1A, 0.5Ω internal switch. Capable of generating 10V at 175mA from a 3.3V input, the LT1949 is ideal for generating bias voltages for large screen LCD panels. Constant frequency 600kHz operation results in a low noise output that is easy to filter and the 30V switch rating allows output voltage up to 28V using a single inductor. An external compensation pin gives the user flexibility in optimizing loop compensation, allowing small low ESR ceramic capacitors to be used at the output. The 8-lead MSOP and SO packages ensure a low profile overall solution.

The LT1949 includes a low-battery detector that stays alive when the device goes into shutdown. Quiescent current in shutdown is 25µA, while operating current is 4.5mA.

Features
  • 1.1A, 0.5Ω, 30V Internal Switch
  • Operates with VIN as Low as 1.5V
  • 600kHz Fixed Frequency Operation
  • Low-Battery Detector Active in Shutdown
  • Low VCESAT Switch: 410mV at 800mA
  • Pin-for-Pin Compatible with the LT1317B
  • Small 8-Lead MSOP Package and SO Packages
Typical Application

Applications
  • LCD Bias Supplies
  • GPS Receivers
  • Battery Backup
  • Portable Electronic Equipment
  • Diagnostic Medical Instrumentation
Packaging

Order Information
Part NumberPackageTempPrice(1-99)Price (1k)*
LT1949EMS8#PBFMS-8E$2.66$2.25
LT1949EMS8#TRPBFMS-8E$2.31
LT1949ES8#PBFSO-8E$2.60$2.20
LT1949ES8#TRPBFSO-8E$2.26
LT1949IS8#PBFSO-8I$2.95$2.50
LT1949IS8#TRPBFSO-8I$2.56
Datasheet
Reliability Data
LT Journal
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LT1949 Footprints and Symbols