The LT1950IGN is a wide input range, forward, boost, flyback and SEPIC controller that drives an N-channel power MOSFET with few external components required.
A resistor programmable duty cycle clamp can be used to generate a volt-second clamp for forward converter applications. An internal boost switcher is available for creating a separate supply for the output gate driver, allowing 10V gate drive from input voltages as low as 3V. The LT1950’s operating frequency can be set with an external resistor over a 100kHz to 500kHz range and a SYNC pin allows the part to be synchronized to an external clock. Additional programmability exists for leading edge blanking and slope compensation.
A fast current sense comparator achieves 60ns current sense delay and the error amplifier is a true voltage mode error amplifier, allowing a wide range of compensation networks. An accurate shutdown pin with programmable hysteresis is available for undervoltage lockout and shutdown. The LT1950IGN is available in a small 16-Pin SSOP package.
Feature
- Wide Input Range: 3V to 25V
- Programmable Volt-Second Clamp
- Output Power Levels from 25W to 500W
- Auxiliary Boost Converter Provides 10V Gate Drive from VIN as Low as 3V
- Programmable Operating Frequency (100kHz to 500kHz) with One External Resistor
- Programmable Slope Compensation
- Programmable Leading Edge Blanking
- ±2% Internal 1.23V Reference
- Accurate Shutdown Pin Threshold with Programmable Hysteresis
- 60ns Current Sense Delay
- 2.5V Auxiliary Reference Output
- Synchronizable to an External Clock up to 1.5 • fOSC
- Current Mode Control
- Small 16-Pin SSOP Package
Applications
- Telecom Power Supplies
- Automotive Power Supplies
- Portable Electronic Equipment
- Isolated and Nonisolated DC/DC Converters
(Picture: Pinout)
