2018 …
A Linear LED driver PSU

Looking for the simplest design with safety built-in I found the TL783 voltage regulator. This is essentially a 700mA device so one of these could easily drive a single panel. However this requires a heat-sink … and even then, the heat generated is significant.


The image on the left is based on one of the application schematics taken from the manufacturer’s (Texas) data-sheet.

The values 3K9 and 82R conveniently produce an output of nominally 60V off-load, dropping to 58V when delivering 550mA. This is sufficient to drive the panel to full brightness.

The TIP112 is a power Darlington capable of sinking 2A, so there is now plenty of ‘headroom’.


This regulator is fed from a conventional transformer / bridge circuit with smoothing pack.