AccurIC Ltd HB-LED drivers: deep-dimming meets high current accuracy and high MTBF

Nov. 7, 2011
Date Announced: 07 Nov 2011 A new UK technology company, AccurIC Ltd (, has completed a research, development and productionisation programme, culminating in the release of a new familiy of LED drivers for the 150-350 mA LED lighting and signage markets.The 'AR' series of constant current drivers, based on a new (patent pending)current regulation technique, provide a Pulse-Width Modulation (PWM) dimming ratio of over 200:1. That in itself would represent a significant step forward for applications requiring deep-dimming. But this capability is delivered by fully-packaged low-side drivers, which also give a current accuracy of +/- 2% over an ambient temperature range of -40C to +55C, an MTBF of 1,700,000 Hrs at 25C ambient, a maximum output voltage (driving the LED string) of 66 V and a maximum efficiency of 92%.And as an added plus, the AR series drivers support strobe and pulse operation.The product family is the result of a collaborative programme, involving Worcester-based AccurIC and its development and production partner, Scimar Engineering Ltd, of Exeter. The underlying technology is the brainchild of Dave Bannister (AccurIC's Managing Director) and Tim Crocker (Managing Director of Scimar) who chose to question the now long-standing assumption that Switch-mode is always the best way to drive LED chains.As Dave (a former research engineer and business development manager with QinetiQ) explained:'SMPS drivers provide the best solution for acheiving high efficiency at low voltage. However, with the emergence of LED lighting applications that don't involve voltages down at 12 V or below, but instead operate at 36 V, 48 V or above, there was a wall waiting to be pushed - so we pushed it.'What also struck us was the fact that issues around Switch-mode ripple and restricted PWM dimming range, were standing in the way of LED lighting acheiving its full green potential'.The AR series, which currently includes drivers for 150, 175, 300 and 350 mA, all come with the following performance features as standard:Deep PWM dimming (down to below 0.5% - a dimming ratio of greater than 200:1)High LED string voltage (up to 66 V)Current accuracy of +/- 2%, over -40C to +55CHigh MTBF (1,700,000 Hrs)Efficiency up to 92%No Switch-mode rippleOver-voltage protectionOver-temperature protectionAccurIC plans to go into full production with the AR series at the end of November.

Dave Bannister, Managing Director AccurIC Ltd

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