Isolated Monolithic Flyback Simplifies Design & Eliminates Optocoupler - LT3573EMSE#PBFLT3573EMSE#PBF
- VIN Range from 3V to 40V
- Onboard 1.25A, 60V Integrated NPN Power Switch
- No Transformer, Third Winding or Opto-Isolator Required for Feedback
- Current Mode Control
- Boundary Mode Operation
- VOUT Set with Two External Resistors
- Programmable Soft-Start
- Programmable Undervoltage Lockout
- Output Voltage Temperature Compensation
- Adjustable Current Limit
The LT3573LT3573 is an isolated monolithic flyback switching regulator with an integrated 1.25A NPN power switch. This device significantly simplifies the design of a flyback converter since it does not require a third winding or optoisolator and can sense the output voltage directly from the primary side flyback waveform. The LT3573LT3573 operates over an input voltage range of 3V to 40V at output power levels up to 7 watts, and can be used in a wide variety of industrial, medical, datacom and automotive applications requiring isolated power.
LT3573EMSE#PBFLT3573EMSE#PBF Schematic
The LT3573LT3573 operates in boundary mode, which is a variable frequency current mode switching scheme, resulting in a total regulation band of ±5% over a wide input voltage range and output load current in a typical application. Boundary mode operation also permits the use of a smaller transformer when compared to equivalent continuous conduction mode designs.
The output voltage is easily set by two external resistors. The LT3573LT3573 has additional features that include an onboard LDO, programmable soft start, undervoltage lockout, adjustable current limit and output voltage temperature compensation. The LT3573LT3573 is available in a small thermally enhanced MSOP-16 package and is offered in an extended and industrial operating junction temperature range at -40°C to 125°C.
More info on www.linear.com/3573 or go to Design Kit Demoboard
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