Texas Instruments LM51551 | Demoboard PMP30523

Description

This reference design is a tiny 3-W auxiliary power supply reference design driving four outputs – two of them isolated to power some drivers. The wide input range is 6 V to 60 V, so 1:10 - here a discrete LDO is needed to expand BIAS voltage for controller LM51551. For lowest EMI, a SEPIC topology is used to ensure low reflected ripple and to avoid RF ringing at the switch node. The control loop is closed on the primary side to save additional cost of optoisolator. Dual feedback allows any weighted feedback in between 3.3-V / 11-V outputs.

Features

Four outputs, two of them isolated 1000 VacPrimary side regulation is used resulting in no need for optoisolatorConverter works in discontinuous conduction mode (DCM) for allowing to use a small transformer and for a reasonable dynamic performance

More information

• Datasheet