Description

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The MAX20444B is a 4-channel backlight driver with boost controller for automotive displays. The integrated current outputs can sink up to 130mA LED current each. The device accepts a wide 4.5V to 36V input voltage range and withstands direct automotive load-dump events.

The internal current-mode switching DC-DC controller supports boost or SEPIC topologies and operates in the frequency range 400kHz to 2.2MHz. Integrated spread spectrum helps reduce EMI. An adaptive output-voltage control scheme minimizes power dissipation in the LED current-sink paths.

The device features I²C-controlled pulse-width modulation (PWM) dimming and hybrid dimming. In either case the minimum pulse width is 500ns. Phase-shifted dimming of the strings is incorporated for lower EMI.

Comprehensive diagnostic information is also available via the I²C interface, while stand-alone operation is also supported.

The MAX20444B is available in a 24-pin TQFN or 24-pin side-wettable TQFN (SWTQFN) package and operates over the -40°C to +125°C temperature range.

Key Features

• Wide-Voltage-Range Operation
  • Operates Down to 4V Supply After Startup
  • Survives Load Dump Up to 52V
• High Integration
  • Complete 4-Channel Solution Including Boost Controller
  • I²C Control for Minimum Parts Count
• Robust and Low EMI
  • Spread-Spectrum Oscillator
  • Phase Shifting
  • 400kHz to 2.2MHz Switching-Frequency Range
  • Fail-Safe Operation Mode Using the FSEN Pin
• Versatile Dimming Scheme Allows Hybrid or PWM-Only Dimming Using DIM Input or I²C
  • Dimming Ratio > 10000:1 Using Hybrid Dimming
  • 10000:1 Dimming Ratio at 200Hz using PWM Dimming
• Complete Diagnostics
  • LED Open/Short Detection and Protection
  • Boost Output Undervoltage and Overvoltage
  • Boost Voltage
  • Individual String LED Current
  • Thermal Shutdown
• Compact (4mm x 4mm) 24-Pin TQFN and SWTQFN Packages

Applications/Uses

• Central Information Displays
• Infotainment Displays
• Instrument Clusters