LED news and insight from our technology editor Steve Bush, who has been messing with LED lighting for more years than he would care to remember.
LED power drivers and tantalum polymer capacitors
A small LED angle on this one – AVX has developed what it claims is the first 63V and 75V single-anode tantalum polymer capacitors, writes Richard Wilson.
The capacitors feature reduced ignition failure mode, making them more robust and less likely to overload, said the supplier.
“These high voltage polymer tantalum capacitors are ideal for a wide range of applications, as AC/DC convertors require both high voltage and high ripple current, which facilitates the low ESR offered by conductive polymer technology,” said Dan Lane, product manager at AVX.
These TCJ series polymer tantalum capacitors are available in 1uF/63V, 4,7uF/63V, 10uF/63V and 4.7uF/75V, 6.8uF/75V rated voltages.
“LED power drivers also have high voltage requirements, as branches of serially connected diodes are used and also require capacitance to function as effectively as possible,” said Lane.
The recommended 20% voltage derating will extend the usable voltage range.
According to the supplier, reliability exceeds 1% per 1000 hours at 85ºC and full-rated voltage.
One target is to replace MLCC ceramic capacitors in circuits such as backlight controllers in LCD monitors and displays.Tags: capacitance, failure mode, richard wilson, voltage range, voltage requirements