MAX17061

The MAX17061 is a high-efficiency driver for white lightemitting diodes (LEDs). It is designed for large liquidcrystal displays (LCDs) that employ an array of LEDs as the light source. An internal switch current-mode step-up controller drives the LED array, which can be configured for up to eight strings in parallel and 10 LEDs per string.Each string is terminated with ballast that achieves ±1.5% current-regulation accuracy between strings, ensuring even LED brightness. The MAX17061 has a wide inputvoltage range from 4.5V to 26V, and provides a fixed 25mA or adjustable 15mA to 30mA full-scale LED current.

Features of the MAX17061 are:(1)accurate dimming control using SMBus, PWM Interface; (2)Dimming Range with 8-Bit Resolution; (3)Adjustable DPWM frequency with 1.5% accuracy; (4)up to eight parallel strings multiple series-connected LEDs; (5)low string feedback voltage: 625mV at 25mA LED current; (6)full-scale LED current adjustable from 15mA to 30mA, or preset 25mA; (7)open and short LED protections; (8)output overvoltage protection; (9)wide input-voltage range from 4.5V to 26V; (10)500kHz/750kHz/1MHz selectable switching frequency; (11)small 28-pin, 4mm x 4mm, thin QFN package.The MAX17061 internally generates a DPWM signal for accurate WLED dimming control. The DPWM frequency is resistor programmable, while DPWM duty cycle is controlled directly from an external PWM signal or through a control word through the MAX17061's SMBus™ interface.This DPWM control provides a dimming range with 8-bit resolution and supports Intel display-power-saving technology (DPST) to maximize battery life.

The absolute maximum ratings of the MAX17061 can be summarized as:(1)IN to AGND:-0.3V to +28V;(2)storage temperature range:-60 to +150;(3)operating temperature range:-40 to +85;(4)junction temperature:+150;(5)PGND_ to GND:-0.3V to +0.3V;(6)continuous power dissipation:1667mW.Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied.Exposure to absolute maximum rating conditions for extended periods may affect device reliability.The MAX17061's fixed-frequency, current-mode, stepup controller automatically chooses the lowest active FB_ voltage to regulate the output voltage. Specifically,the difference between the lowest FB_ voltage and the current-source control signal plus an offset (VSAT) is integrated at the CCV output.