LM36922HYFFR Mosfet Power Transistor LED Lighting Drivers Backlight with an inverter

LM36922HYFFR Mosfet Power Transistor LED Lighting Drivers Backlight with an inverter

1 Features

• 1% Matched Current Sinks Across Process, Voltage, Temperature

• 3% Current-Sink Accuracy Across Process, Voltage, Temperature

• 11-Bit Dimming Resolution

• Up to 90% Solution Efficiency

• Drives from One to Two Parallel LED Strings at up to 38 V at 25 mA per String

• PWM Dimming Input

• I2C Programmable

• Selectable 500-kHz and 1-MHz Switching Frequency With Optional –12% shift

• Auto Switch Frequency Mode (250 kHz, 500 kHz, 1 MHz)

• Four Configurable Overvoltage Protection Thresholds (17 V, 24 V, 31 V, 38 V)

• Four Configurable Overcurrent Protection Thresholds (750 mA, 1000 mA, 1250 mA, 1500 mA)

• Thermal Shutdown Protection

• Externally Selectable I2C Address Options via ASEL Input

  
  

2 Applications

• Power Source for Smart Phone and Tablet Backlighting

The LM36922H is an ultra-compact, highly efficient, two-string white-LED driver designed for LCD display backlighting. The device can power up to 12 series LEDs at up to 25 mA per string. An adaptive current regulation method allows for different LED voltages in each string while maintaining current regulation.

The LED current is adjusted via an I2C interface or through a logic level PWM input. The PWM duty cycle is internally sensed and mapped to an 11-bit current thus allowing for a wide range of PWM frequencies with noise-free operation from 50 μA to 25 mA.

Other features include an auto-frequency mode, which can automatically change the frequency based on load current in order to optimize efficiency.

The device operates over the 2.5-V to 5.5-V input voltage range and a –40°C to +85°C temperature range.

Device Information