Programmable LED Blinker Device Takes Load Off Processors

It’s no longer necessary to keep a microprocessor in continuous operation just to blink an LED, thanks to the FAN5646, a programmable LED blinker. With the company’s TinyWire single-wire digital interface, the FAN5646 can be programmed with a unique LED blink rate and pattern. When the FAN5646 is enabled it will continually play these LED blink patterns until commanded by the microprocessor to stop. Common approaches used in the past to solve this challenge include connecting the LED to a low-dropout regulator or a FET and a Li-ion battery. Both of these implementations require a microprocessor to be programmed with a blinking pattern, which lessens battery life because the microprocessor needs to be continually operating to maintain this pattern. In contrast, the FAN5646 minimizes system power consumption by enabling the microprocessor to be left in sleep mode while the blinker is in operation. The single-wire digital interface allows programming of up to two different pulse widths and blink rates. The blinker’s very low 80-mV dropout voltage means the LED can be powered without need for inductors or switching capacitors, minimizing component counts. Package options include a WL-CSP version and a five-lead SC70. Pricing is $0.50 each in lots of 1000. Samples are available now; production quantities have a 12-week lead time. FAIRCHILD SEMICONDUCTOR, San Jose, CA. (408) 822-2000.