MAX16838B:Integrated, 2-Channel, High-Brightness LED Driver with High-Voltage Boost and SEPIC Controller

Industry's Only 2-String HB LED Driver for Automotive Applications Provides 10000:1 Dimming Ratio

The MAX16838B is a dual-channel LED driver that integrates both the DC-DC switching boost regulator and two 150mA current sinks. A current-mode switching DC-DC controller provides the necessary voltage to both strings of HB LEDs. The device accepts a wide 4.75V to 40V input voltage range and directly withstands automotive load-dump events. For a 5V ±10% input voltage, connect VIN to VCC. The wide input range allows powering HB LEDs for small-to-medium-sized LCD displays in automotive and display backlight applications. An internal current-mode switching DC-DC controller supports the boost or SEPIC topologies and operates in an adjustable frequency range between 200kHz and 2MHz. The current-mode control provides fast response and simplifies loop compensation. The device also features an adaptive output-voltage adjustment scheme that minimizes the power dissipation in the LED current- sink paths. The MAX16838B can be combined with the MAX15054 to achieve a buck-boost LED driver with two integrated current sinks. The channel current is adjustable from 20mA to 150mA using an external resistor. The external resistor sets both channel currents to the same value. The device allows connecting both strings in parallel to achieve a maximum current of 300mA in a single channel. The MAX16838B also features pulsed dimming control with minimum pulse widths as low as 500ns on both channels through a logic input (DIM). The device includes output overvoltage protection, open-LED/shorted-LED detection, and overtemperature protection. The device is available in 20-pin TSSOP (4.4mm) and TQFN (4mm x 4mm) packages and operates over the -40°C to +125°C automotive temperature range.

Key Features
  • High Integration Provides for a Compact Solution
    • Integrates 2-Channel, 20mA to 150mA Linear LED Current Sinks
    • Internal Slope Compensation and Switching MOSFET
  • Flexible IC Fits Many Applications
    • Boost or SEPIC Converter Topologies
    • Wide 4.75V to 40V or 5V ±10% Input Operating Range
    • 200kHz to 2MHz Resistor-Programmable Switching Frequency with External Synchronization
  • Wide Contrast Ratio Ideal for High Quality TFT and Head-Up Displays
    • PWM Dimming Ratio of 10,000:1 at 200Hz
  • Robust with Respect to Temperature and Fault Conditions
    • Current Foldback Reference Input
    • LED Open/Short Detection and Protection
    • Output Overvoltage and Overtemperature Protection
    • Thermally Enhanced 20-Pin TSSOP (4.4mm) and TQFN (4mm x 4mm) Packages
MAX16838B: System Block Diagram
MAX16838B: System Block Diagram
Applications/Uses
  • Automotive Display Backlights
  • Automotive Lighting Applications
  • LCD Display Backlights
DataSheet
titleDownload file
MAX16838B Data SheetMAX16838B.pdf
Parametrics
Part NumberRegulation TopologyMax. No. of LEDsLED ChannelsLED ConfigurationILED per Channel
(A)
PWM Dimming Freq.
(kHz)
Dimming RatioDimming ControlPOUT
(W)
VIN
(V)
VIN
(V)
ICC
(mA)
LED String Volt.
(V)
Oper. Freq.
(kHz)
Package/Pins
maxmaxmaxminmaxmaxmax
MAX16838BInductor Based
Linear
222Series-Parallel0.152010000PWM104.5540540250
262
300
500
750
1000
1200
1500
2000
TQFN/20
TSSOP-EP/20
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX16838BATP/V+Future ProductTQFN,;20 pin;16.8 mm²-40°C to +125°CLead Free
MAX16838BATP/V+TFuture ProductTQFN,;20 pin;16.8 mm²-40°C to +125°CLead Free
MAX16838BAUP/V+ActiveTSSOP-EP,;20 pin;42.9 mm²-40°C to +125°CLead Free
MAX16838BAUP/V+TActiveTSSOP-EP,;20 pin;42.9 mm²-40°C to +125°CLead Free
MAX16838B.pdf MAX16838B
MAX16838B.pdf MAX16838B
MAX16838B.pdf MAX16838B
MAX16838B.pdf MAX16838B
MAX16838B.pdf MAX16838B