Monolithic Power Systems MP3385 | Demoboard EV3385-R-00A

Description

The MP3385 is a step-up controller with 4regulated current channels designed to driveWLED arrays for middle and large-size LCDpanel backlighting applications.The MP3385 uses peak current mode, PWMcontrol architecture for system loop regulation.It drives an external MOSFET to boost up theoutput voltage from a 4.5V to 33V input supply.It employs an I2C digital interface and canflexibly set the operation and protection modes,including dimming mode, dimming current anddimming ratio, OCP, OVP, LED short protectionthreshold, and the switching frequency. Foreasy application use and board debugging, theMP3385 detects and automatically disables theunused LED strings during start-up to avoidcharging the output to the OVP threshold.The MP3385 achieves 1.8% current matchingbetween each string. The low regulation voltageon the LED current sources improves efficiencyand reduces power loss in order to achieve ahigher current output.The MP3385 supports analog, PWM, andcombined analog and PWM dimming modes tomeet different application requirements. Fullprotection features include OCP, OTP, UVP,OVP, LED short/open protection, andinductor/diode short protection.The MP3385 is available in a QFN-204mm x 4mm and a TSSOP20-EP package.

Features

• 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 EachString
• Unused Channel Auto-Detection Functionduring Start-Up
• 100kHz-900kHz Programmable SwitchingFrequency
• Multiple Dimming Modes Selected by I2CInterface:

1. Direct PWM Dimming Mode

2. Internal Fixed 23kHz PWM DimmingMode

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 Currentwith 8-Bit Resolution
   • 0%-100% LED Dimming Range with 10-BitResolution for Internal Dimming Mode
   • Cascading Capability with a Single PowerSource
   • 18V to 80V Over-Voltage Protection,2V/Step
   • 0.15V to 0.5V Latch-Off/Recoverable OCPProtection Threshold, 50mV/Step
   • Recoverable Thermal Shutdown Protection

Typical applications

• Desktop LCD Flat Panel Displays
• 2D/3D LCD TVs
• All In One

More information

• Datasheet
• IC product information