LED driver for big (and little) LCD TVs

The iW7011 by iWatt, is a 6-channel LED driver with built-in intelligent digital control engine. Designed to reduce the BOM cost and simplify the design of both edge-lit and direct-lit LCD TVs, the driver integrates a number of design features including:

• On-board boost controller provides a high-voltage power supply for external LED strings.
• The digital control engine allows real-time control of phase delays while managing Vsync synchronization and fault readouts.
• An 85V capability on drain sensing eliminates cascodes or zener clamps.
• High voltage drain sensing eliminates external diodes typically required for LED short-circuit fault management.

 

The digital control engine improves overall system efficiency by optimizing the DC-to-DC voltage. It also generates the current sink PWM waveforms, processes the fault conditions, and reports on all faults. The iW7011 enables accurate dimming control, with 14-bit resolution at 120Hz PWM frequency. It offers phase-shifted dimming of the current sinks either through direct PWM mode or through an SPI interface. An optional 8-bit analog register can be used to increase the dimming resolution. Phase-shifted dimming reduces capacitance demand on the input and output to improve both dimming linearity and EMI performance.

Four phase-shift dimming options are available: three fixed options for 6-channel operation and an adaptive phase shift option where the shift is evenly distributed based on the number of active channels. The iW7011 is packaged in a 44-pin, 10mm x 10mm, thin QFP with 0.8 mm pitch and a pin-out optimized for single-layer PCB layout.

The iW7011 LED driver is available in production quantities. Samples are available at $1.10 in 1000-piece quantities. Product brief is available here.

 

For more information, visit iWatt.

 

Download datasheets for LED drivers at Datasheets.com.