MAX16826:Programmable, Four-String HB LED Driver with Output-Voltage Optimization and Fault Detection

Programmable, Four-String LED Driver with Integrated ADC Optimizes Output Voltage and Detects LED Fault Conditions

The MAX16826 high-brightness LED (HB LED) driver is designed for backlighting automotive LCD displays and other display applications such as industrial or desktop monitors and LCD televisions. The MAX16826 integrates a switching regulator controller, a 4-channel linear current sink driver, an analog-to-digital converter (ADC), and an I2C interface. The IC is designed to withstand automotive load dump transients up to 40V and can operate under cold crank conditions. The MAX16826 contains a current-mode PWM switching regulator controller that regulates the output voltage to the LED array. The switching regulator section is configurable as a boost or SEPIC converter and its switching frequency is programmable from 100kHz to 1MHz. The MAX16826 includes 4 channels of programmable, fault-protected, constant-current sink driver controllers that are able to drive all white, RGB, or RGB plus amber LED configurations. LED dimming control for each channel is implemented by direct PWM signals for each of the four linear current sinks. An internal ADC measures the drain voltage of the external driver transistors and the output of the switching regulator. These measurements are then made available through the I2C interface to an external microcontroller (µC) to enable output voltage optimization and fault monitoring of the LEDs. The amplitude of the LED current in each linear current-sink channel and the switch-mode regulator output voltage is programmed using the I2C interface. Additional features include: cycle-by-cycle current limit, shorted LED string protection, and overtemperature protection. The MAX16826 is available in a thermally enhanced, 5mm x 5mm, 32-pin thin QFN package and is specified over the automotive -40°C to +125°C temperature range.

Key Features
  • 4 Channels of Programmable, Fault-Protected, Constant-Current Source-Driver Controllers for All White, RGB, or RGB Plus Amber LED Configurations
    • Drives One to Four LED Strings
    • Individual PWM Dimming Inputs per String
    • Very Wide Dimming Range
  • Configurable as a boost or SEPIC Converter with Programmable 100kHz to 1MHz Switching Frequency for Design Flexibility
    • Integrated Boost/SEPIC Controller
    • External MOSFETs Allow Wide-Range LED Current with Multiple LEDs per String
    • 200kHz to 2MHz Programmable Switching Frequency for Optimizing Size vs. Efficiency
    • External Switching-Frequency Synchronization
  • I2C Allows the Current-Sink Drain Voltages to be Read to Minimize Power Dissipation and Detect LED String Fault Conditions
    • 7-Bit Internal ADC for LED Voltage Monitoring and Optimization
    • Dynamic Adjustment of LED String Currents and Output Voltage
    • Standby Mode
  • Protection Features Improve Reliability
    • LED Short and Open Detection
    • Overvoltage and Overtemperature Protection
MAX16826: Simplified Block Diagram
MAX16826: Simplified Block Diagram
Applications/Uses
  • LCD Backlighting:
  • Automotive Infotainment Displays
  • Automotive Cluster Displays
  • Industrial and Desktop Monitors
  • LCD TVs
  • Automotive Lighting:
  • Adaptive Front Lighting
  • Low- and High-Beam Assemblies
DataSheet
titleDownload file
MAX16826 Data SheetMAX16826.pdf
Parametrics
Part NumberRegulation TopologyMax. No. of LEDsLED ChannelsLED ConfigurationILED per Channel
(A)
PWM Dimming Freq.
(kHz)
Dimming RatioDimming ControlVCURR_SENSE
(mV)
POUT
(W)
VIN
(V)
VIN
(V)
ICC
(mA)
LED String Volt.
(V)
Oper. Freq.
(kHz)
Package/PinsBudgetary
Price
maxmaxmaxminmaxmaxmaxSee Notes
MAX16826Inductor Based1004Series-Parallel11005000I2C Serial
PWM
991004.7524101001000QFND/32
TQFN/32
$3.19 @1k
Design kits & evaluation modules
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX16826AGJ/VY+ActiveQFND,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826AGJ/VY+TActiveQFND,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ+ActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ+C24ActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ+TActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ+TC24Custom OrderTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ/V+ActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ/V+TActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ/VY+ActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826ATJ/VY+TActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX16826BATJ+ActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826BATJ+TActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826BATJ/V+ActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826BATJ/V+TActiveTQFN,;32 pin;26 mm²-40°C to +125°CLead Free
MAX16826.pdf MAX16826
MAX16826.pdf MAX16826
MAX16826.pdf MAX16826
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