Power Integrations has introduced a reference design for an 18W non-isolated A19 LED driver that is 88%-efficient, writes Richard Wilson.
The design is intended for a 100W incandescent bulb replacement and will support low-line (90 VAC to 135 VAC) operation.
“The lighting industry typically asks for 80% efficiency for drivers targeting 60W A19 bulb replacements. To achieve viable LED-based replacements for 75W and 100W bulbs, much higher efficiency is needed in order to reduce the heat dissipated by the driver,” said Andrew Smith, product marketing manager at Power Integrations.
Designated the DER-323, the reference design uses a buck-boost converter topology that fits inside the A19 bulb.
“The 88% efficiency of DER-323 makes the thermal design of the bulb straightforward and inexpensive,” said Smith.
The circuit will fit on a single-sided board and 25 components. No potting is necessary and the transformer is replaced by a low-cost inductor.
The design is EN61000-3-2 (C) compliant and has a high power factor of over 0.98.
Based on a LNK460VG LinkSwitch-PL IC it combines both PFC and CC converter functions in a single-stage topology, no electrolytic bulk capacitor is required, resulting in a very long operational life.