The RT8555AWSC is a high efficiency driver for white LEDs. It is suitable for single/two cell battery input to drive LED light bars which contains six strings in parallel and up to 10 WLEDs per string. The internal current sinks support a maximum of ±2% current mismatching for excellent brightness uniformity in each string of LEDs. To provide enough headroom for current sink operation, the Boost controller monitors the minimum voltage of the feedback pins and regulates an optimized output voltage for power efficiency. The RT8555AWSC has a wide input voltage operating range from 2.7V to 24V and contains I2C interface for controlling the dimming mode, operating frequency and the LED current. The internal 100mΩ, 36V power switch with current-mode control provides over-current protection. The switching frequency of the RT8555AWSC is adjustable from 300kHz to 2MHz, which allows flexibility between efficiency and component size. The RT8555AWSC is available in the WL-CSP-20B 1.65 x 2.05 (BSC), with pitch 0.4mm package.
Feature
- Wide Operating Input Voltage : 2.7V to 24V
- High Output Voltage : Up to 36V
- Programmable Channel Current : 10mA to 35mA
- Channel Current Regulation with Accuracy ±3% and Matching ±2%
- Dimming Controls► Direct PWM Dimming up to 20kHz and Minimum On-Time to 400ns► PWM to Analog Dimming up to 20kHz with 8-bit Resolution
- I2C Programs LED Current, Switching Frequency, Dimming Mode
- Embedded Memory by OTP
- Switching Frequency : 300kHz to 2MHz
- Protections► LED Strings Open Detection► Current Limit ► Programmable Over Voltage Protection► Over-Temperature Protection
- 20-Ball WL-CSP, with pitch 0.4mm Package
- RoHS Compliant and Halogen Free
Applications
- Tablet and Notebook Backlight
