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I want to drive an LED with 4A current in pulses of 1-4 msec. The CAT3324 seems able to do this, but I am uncertain about the readiness of the supercapacitors. For example, CDE type EDL capacitors have a maximum recommended current of less than 1 mA. Even the expensive AVX Bestcaps must be substantially derated when used in the msec range, and it is not clear that they support 1-msec pulses at all. Can you recommend a supercap suitable for this application?

The CAT3224 driver uses a supercapacitor in order to store the energy to drive an LED at 4A. The capacitor should have a large capacitance value with very low ESR (around 100 milli ohm or less) and with a voltage rating of 5.5V or higher.\n\nFor camera flash application, you might consider dual cell supercapacitors that are available from vendors like Cap-XX, Murate, TDK...\n\nThe size of the capacitor depends on the maximum flash duration and other parameters. Please refer to the data sheet for calculating the capacitor value.\n\nhttp://www.onsemi.com/pub_link/Collateral/CAT3224-D.PDF Answered by:
ON Semiconductor
2012-10-18 16:28:05.0