LTC3805EMSE#PBF

LTC®3805 is a current mode controller for flyback DC/DC converters designed to drive an N-channel MOSFET in high input and output voltage converter applications. Operating frequency and slope compensation can be programmed by external resistors. Programmable overcurrent sensing protects the converter from short-circuits. Soft-start can be programmed using an external capacitor and the soft-start capacitor also programs an automatic restart feature. This provides ±1.5% output voltage accuracy and consumes only 360µA of quiescent current during normal operation and only 40µA during micropower startup. Using a 9.5V internal shunt regulator, this can be powered from a high VIN through a resistor or it can be powered directly from a low impedance DC voltage of 9V or less. Typical applications are telecom power supplies, 42V and 12V automotive power supplies, isolated electronic equipment.

• VIN and VOUT limited only by external components
• Adjustable slope compensation, adjustable overcurrent protection with automatic restart
• Adjustable operating frequency (70KHz to 700KHz) with one external resistor
• Synchronizable to an external clock, ±1.5% reference accuracy
• Current mode operation for excellent line and load transient response
• RUN pin with precision threshold and adjustable hysteresis
• Programmable soft-start with one external capacitor
• Input DC supply current is 360µA (normal operation (fOSC=200KHz))
• 10-lead plastic MSOP package
• Temperature rating range from –40°C to 85°C

Notes

ADI products are only authorized (and sold) for use by the customer and are not to be resold or otherwise passed on to any third party