15V 1A Dual Output Flyback DC-DC Converter

Rajkumar Sharma        
614
Project tested

+/-15V 1A Dual output DC-DC converter is a tiny board built using Transformer from Renco and LM2587-ADJ IC from Texas instrument.  Input supply 18-36V DC.  The LM2587 regulators is monolithic integrated circuit specifically designed for fly back, step-up (boost), and forward converter applications. The power switch is a 5.0A NPN device that can stand-off 65V. Protecting the power switch are current and thermal limiting circuits, and an under voltage lockout circuit. This IC contains a 100 kHz fixed frequency internal oscillator that permits the use of small magnetics. Other features include soft start mode to reduce in-rush current during start up, current mode control for improved rejection of input voltage and output load transients and cycle-by-cycle current limiting. An output voltage tolerance of ±4%, within specified input voltages and output load conditions, is ensured for the power supply system.

Features

  • Supply Input 18-36V DC
  • Output +/-15V DC, 1Amp
  • On board trimmer potentiometer for Fine voltage adjust
  • Operation Frequency 100 KHz

Schematic

Parts List

Photos

Video

PCB

One Response on “15V 1A Dual Output Flyback DC-DC Converter

  1. Hi.
    I enjoy seeing concepts take to implementation, great. I have been doing such work for 20 years+ and I have a few suggestions.

    You might consider input filters and common mode chokes, flybacks with high dI/dT are very noisy. A small cap from input GND to output GND will by pass RFI which results from primary to secondary transformer capacitance. Use something like Titan Magnetics software to optimize magnetic design, off shelf parts seldom result with duty cycles near 50%. This pushes up the already high flyback peak currents.

    Contact me I would be happy to help, you might take a look at my sunduino web site, there is a lot of data about product design.

    Consider 4 layer PCBs, they do not cost that much more and they give you many options for nice, low Z copper planes. Well worth the price. This is required id you really want to manage RFI, and flybacks are VERY noisy.

    Bob

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