AS3693C Backlighting IC

Description

The AS3693C is a 9 channels high precision LED controller with build in PWM generators for driving external FETs in LCD-backlight panels.

External clock and synchronizing inputs allow the synchronization of the LCD backlight with the TV picture. Local dimming and scan dimming is supported by 9 independent PWM generators with programmable delay, period and duty cycle. Three free configurable dynamic power feedback circuits make the device usable for white LED as well as RGB backlights. Build in safety features include thermal shutdown as well as open and short LED detection. All circuit parameters are programmable via I2C or SPI interface.

Key Features

• 9 Channel LED driver
• Output current only limited by external transistor
• Output voltage 0.4V to 50V
• Absolute current accuracy +/- 0.5%
• Output slew rate programmable
• Current programmable with external resistor
• Linear current control with 8 - bit DAC
• Linear current control with external analog voltage
• Digital current control with 9 independent PWM generators
• Free programmable 12 bit resolution ( period, high time and delay )
• Overvoltage detection ( short LED )
• Undervoltage detection ( open LED )
• Temperature shutdown
• Fault interrupt output
• H-Sync, V-Sync inputs to synchronize with TV-set
• Internal or external PWM – clock
• I2C interface
• SPI interface
• 5 bit device - address (sets device address and interface mode)
• Automatic supply regulation feedback
• Each output can be assigned to red, green or blue feedback.
• Package LQFP44 LD 10x10mm

Applications

• LED backlighting for LCD – TV sets and monitors

Block diagram for AS3693C Backlighting IC