MAX16826

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


Description

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.

MAX16826: Simplified Diagram MAX16826: Simplified Diagram Enlarge+

Key Features

  • External MOSFETs Allow Wide-Range LED Current with Multiple LEDs per String
  • Individual PWM Dimming Inputs per String
  • Very Wide Dimming Range
  • LED String Short and Open Protection
  • Adjustable LED Current Rise/Fall Times Improve EMI Control
  • Microcontroller Interface Using I²C Allows
    • LED Voltage Monitoring and Optimization Using a 7-Bit Internal ADC
    • LED Short and Open Detection
    • Dynamic Adjustment of LED String Currents and Output Voltage
    • Standby Mode
  • Integrated Boost/SEPIC Controller
  • External Switching Frequency Synchronization
  • 4.75V to 24V Operating Voltage Range and Withstands 40V Load Dump
  • Overvoltage and Overtemperature Protection

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
Part Number Regulation Topology Max. No. of LEDs LED Channels LED Configuration ILED per Channel
(A)
PWM Dimming Freq.
(kHz)
Dimming Ratio Dimming Control VCURR_SENSE
(mV)
POUT
(W)
VIN
(V)
VIN
(V)
ICC
(mA)
LED String Volt.
(V)
Oper. Freq.
(kHz)
Budgetary
Price
max max max min max max max See Notes
MAX16826  Inductor Based 100 4 Series-Parallel 1 100 5000
I2C Serial
PWM
99 100 4.75 24 10 100 1000 $1.89 @1k
See All LED Drivers (74)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.


MAX16826EVKIT: Evaluation Kit for the MAX16826

Design Tools

Modeling/Simulation
MAX16826 LED Driver Macromodel

 

Related Resources


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