- 4-String, Max 300mA/String WLED Driver
- 4.5V to 33V Input Voltage Range
- 80V Abs. Rating for Each String
- 1.8% Current Matching Accuracy for Each String
- Unused Channel Auto-Detection Function during Start-Up
- 100kHz-900kHz Programmable Switching Frequency
- Multiple Dimming Modes Selected by I2C Interface:
- 1. Direct PWM Dimming Mode
- 2. Internal Fixed 23kHz PWM Dimming Mode
- 3. Analog Dimming Mode by Input Pulse
- 4. Internal Analog Dimming Mode
- 5. Mixed Dimming Mode by Input Pulse
- 6. Internal Mixed Dimming Mode
- 2%-100% Programmable Full Scale Current with 8-Bit Resolution
- 0%-100% LED Dimming Range with 10-Bit Resolution for Internal Dimming Mode
- Cascading Capability with a Single Power Source
- 18V to 80V Over-Voltage Protection, 2V/Step
- 0.15V to 0.5V Latch-Off/Recoverable OCP Protection Threshold, 50mV/Step
- Recoverable Thermal Shutdown Protection
- Ishutdown (µA)1
- Vin (max) (V)33
- fsw (min) (kHz)100
- Ichannel (max) (A)0.3
- LEDx ABS Voltage (V)80
- fsw (max) (kHz)900
- Vfb (V)0.6
- PackageQFN-20 (4x4)
- Power MOSFETExternal
- Dimming (Output)P-Dim, A-Dim
- Iq (mA)3
- Typical LCD Screen SizesMedium (10"-29"), Large (30"-45")
- Other FeaturesCascade, I2C, Inductor Short Protection
4 String WLED Controller With I²C Interface Evaluation Board
The MP3385 is a step-up controller with 4 regulated current channels designed to drive WLED arrays for middle and large-size LCD panel backlighting applications.
The MP3385 uses peak current mode, PWM control architecture for system loop regulation. It drives an external MOSFET to boost up the output voltage from a 4.5V to 33V input supply.
It employs an I2C digital interface and can flexibly set the operation and protection modes, including dimming mode, dimming current and dimming ratio, OCP, OVP, LED short protection threshold, and the switching frequency. For easy application use and board debugging, the MP3385 detects and automatically disables the unused LED strings during start-up to avoid charging the output to the OVP threshold.
The MP3385 achieves 1.8% current matching between each string. The low regulation voltage on the LED current sources improves efficiency and reduces power loss in order to achieve a higher current output.
combined analog and PWM dimming modes to meet different application requirements. Full protection features include OCP, OTP, UVP, OVP, LED short/open protection, and inductor/diode short protection.
The MP3385 is available in a QFN-20 4mm x 4mm and a TSSOP20-EP package.
US$ 100.00 + tax