Single Switch Flyback Circuit Converts + 5 VDC to +/- 12 VDC for RS-232 and RS-422 Applications

Reference design by: Texas Instruments

Single Switch Flyback Circuit Converts + 5 VDC to +/- 12 VDC for RS-232 and RS-422 Applications
Developing bipolar 12 volt supplies from a single +5 volt input can be accomplished using a number of conventional approaches. A boost converter is the most logical for the +12 volt output, however it cannot be used in some Interface circuit applications