The Quick Convert is a low cost DC converter design used to provide multiple regulatedoutput voltages using a low cost wall transformer as a power source. A low cost 100Khz flyback transformer was designed to provide 10 watts of power at +5, +3.3, +13 and -13 volts.

Assembled PCB board with small heat sink. All parts are through hole on a double sided PCB.

This transformer is being produced offshore and is available at low cost and in small quantities.

A small printed circuit board (3 x 3 inches) has been designed with the gerber files and schematic files available at no charge. Click Here to submit a name and email address, the Quick Convert reference design will be sent via email.

A Theory of Operation can be downloaded in PDF format, Click Here for this manual.

The complete Quick Convert PCB along with wall transformer, connector and heat sink is available for $75. Low cost transfomrers for OEM application are also available. See the Price List for cost and available items.

Technical notes:

The 13 volt outputs were chosen to allow precision regulation of 12 volt when required, for example FLASH memory programming voltages. The +5 and +3.3 are specified for 1 Amp operation each, however you can draw 2 Amp if one output is not used. These outputs use a single, 2 Amp split winding.

Output noise on +5 output with all outputs at full load. Scope settings: 50mv and 10us / div. Download Theory of Operation Manual.

Operating range is from 8 volts to 30 volts. Much higher operation is possible but the input capacitor voltage and frequency compensation network require change. At higher input voltages the design can provide 15 to 20 watts. Full load input current at 8 volts is 2.2 Amps, at 12 volt input 1.25 Amps. The low voltage shutdown point is controlled using a zener diode. Soft start and remote shutdown has been included.

Total cost of the design, as show, is slightly under US$20. A major portion of this is connectors, PCB and common mode chokes. You can reduce the number and size of components and reduce the cost below US$10.

Through hole components and low cost electrolytic capacitors can be replaced with SMT components for a significant saving in board space.

While the Quick Convert was designed to provide regulated outputs from an unregulated wall transformer, use with regulated source provides additional output voltages. Outputs of + 24, -24, -9 and -15 are available at low power levels.

Heavy GND and VIN copper areas provide low power heat sinks for the LT1170. Operation above 1 Amp (Input Current) requires an additional heat sink. The heat sink shown in the photo provides 40 Degree rise in free air at 8 volt operation with full output power.

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