Analog Devices buck/ boost LED drivers allow LED bias when the input voltage is either above or below the LED voltage. The application note shows the design specifications, schematic, bill of materials ( BOM), and performance data. Buck boost converter led driver. With constant current LED driver, it' s best to connect LEDs in series, so that all LEDs get the same exact current. This is ideal in cases such as a single cell lithium- ion ( Li- Ion) battery driving a single LED where the input voltage can vary from 4.
5V per white LED. Abstract: This reference design is for a buck- boost LED driver. Analog Devices step- up ( boost) LED drivers provide current control of multiple LEDs and support for high brightness LED lighting, large format LED backlighting, camera- enabled smart devices, and a range of related applications. The default constant current output mode is ' Buck- Boost', but with a simple change in wiring this driver can run in ' Boost- Only' mode as well. Operation at a fixed switching frequency of 1 MHz allows the device to be used with small value external ceramic capacitors and inductor. 2 V fully charged down to 2.
The LuxDrive™ A011 series FlexBlock™ is a dual- mode boosting LED power solution for driving high- brightness LED( s). The supply voltage has to be at least 2V or so higher than LED' s total forward voltage, which is around 3. Members of this portfolio include I2C- compatible programming interfaces. The MAX16834 current- mode high- brightness LED driver is featured, and the MAX16834 EV ( evaluation) kit is used to implement the design. Depending on the power supply voltage, Poorman' s Buck can drive up to 6 LEDs connected in series. 7 V fully depleted.
The CAT4238 is a DC- DC step- up converter that delivers an accurate constant current ideal for driving LEDs.