Integrated 16-Channel LED Driver with Switch-Mode Boost and SEPIC Controller

The MAX16809 is an integrated, high-efficiency white or RGB LED driver. It is designed for LCD backlighting and other LED lighting applications with multiple strings of LEDs. The MAX16809's current-mode PWM controller regulates the necessary voltage to the LED array. Depending on the input voltage and LED voltage range, this device can be used with boost or buckboost (SEPIC) topologies.

The MAX16809 LED driver includes 16 open-drain, constant-current-sinking LED driver outputs rated for 36V continuous operation. The LED current-control circuitry achieves ±3% current matching among strings and enables paralleling of outputs for LED string currents higher than 55mA. The output-enable pin is used for simultaneous PWM dimming of all output channels. Dimming frequency range is 50Hz to 30kHz and dimming ratio is up to 5000:1. The constant-current outputs are single resistor programmable and the LED current can be adjusted up to 55mA per output channel.

The MAX16809 operates either in stand-alone mode or with a microcontroller (µC) using an industry-standard, 4-wire serial interface.

The MAX16809 includes overtemperature protection, operates over the full -40°C to +125°C temperature range, and is available in a 5mm x 7mm thermally enhanced, 38-pin TQFN exposed paddle package.

Applications

* LCD White or RGB LED Backlighting: * LCD TVs, Desktop, and Notebook Panels * Industrial and Medical Displays * Ambient, Mood, and Accent Lighting

* 16 Constant-Current Output Channels (Up to 55mA Each)

* ±3% Current Matching Among Outputs

* Paralleling Channels Allows Higher Current per LED String

* Outputs Rated for 36V Continuous Voltage

* Output-Enable Pin for PWM Dimming (Up to 30kHz)

* One Resistor Sets LED Current for All Channels

* Wide Dimming Ratio Up to 5000:1

* Low Current-Sense Reference (300mV) for High Efficiency

* 8V to 26.5V Input Voltage or Higher with External Biasing Devices

* 4-Wire Serial Interface to Control Individual Output Channels