Top

6-Switch Sequential LED Controller For Automotive Lighting Systems

Design Sequential Turn Applications Without the Need of a Microcontroller or Software

Product Details

The MAX25605 is a six-channel automotive sequential LED controller. The device implements a sequential turn function or any other sequential light animation without the use of a microcontroller or software. The MAX25605 integrates six cascoded low RDSON n-channel MOSFETs suitable for LED lighting applications up to 750mA. Each switch supports up to three series LEDs per switch. The entire LED string voltage supported is up to 60V. The n-channel MOSFETs are divided into two groups of three, allowing a single device to sequence either one or two strings of LEDs. Integrated gate drivers and level shifters for the switches are supplied by an internal charge-pump regulator, supporting buck-boost and boost-to-battery applications, in addition to ground-referenced LED driver topologies

Sequencing functionality and timing is programmed by connecting resistors to the A0, A1, A2, and CLK inputs. Programming options include: dimming up/down, short LED threshold, multi-device sequence position, dimming frequency, and fade duration. The optional logarithmic fade feature allows for gradually turning the LEDs on or off. The sequence can be disabled by pulling the enable input low. With EN pulled low, the switches are open and the LED driver current flows through the entire LED string. Each switch also integrates single-LED fault detection, asserting a fault flag in case of shorted LEDs, open LEDs, or open wires between the sequencer and the LED string. Additionally, up to 16 devices can be sequenced together through the use of a SYNC input.

The MAX25605 operates over the -40°C to +125°C automotive temperature range and is available in a 20-pin 4mmx4mm side-wettable TQFN and a 20-pin TSSOP package with exposed pad.

Key Features

 
  • Flexible Dimming Configuration Provides Optimal Performance​ without a Microcontroller or Software
    • Simple Resistor Programming for Sequence Timing and Direction.
    • Hazard Light Applications
    • Sync Pin Allows Sequencing of up to 16 Devices
    • Optional Logarithmic LED Fade
  • Flexible Configuration Allows the Use of the Same Device in Different Applications​
    • One, Two, or Three Series LEDs per Switch
    • Floating Source MOSFETs
  • EMI Reduction
    • Spread-Spectrum Oscillator
    • Slew Rate Control Minimizes LED Current Spikes
  • Protection Features and Package Improve Reliability
    • Single-LED Short, Open, and Open-Trace Detection
    • Thermal Shutdown and Fault Flag
  • Automotive Ready
    • AEC-Q100 Qualified
    • -40°C to +125°C Operating Temperature Range

Applications/Uses

  • Hardware-Based Lighting Animation
  • Sequential Turn Signal Lights
Parametric specs for LED Drivers
VIN (V) (min) 4
VIN (V) (max) 60
Max. No. of LEDs 18
# LED Channels 6
LED Configuration Series-Parallel
ILED per Channel (A) (max) 0.75
Dimming Control Resistor Programming
ICC (mA) (max) 5
LED String Volt. (V) (max) 60
Package/Pins TQFN/20
Budgetary
Price (See Notes)
$2.19 @1k
View More

Technical Docs

Design & Development

Click any title below to view the detail page where available.

Description

The MAX25605 evaluation kit (EV kit) provides a proven design to evaluate the MAX25605 6-switch sequential LED controller for automotive lighting systems. The MAX25605 EV kit demonstrates a complete sequential lighting design, including an on-board timing circuit, two MAX25611 LED drivers configured as boost-to-battery (battery referenced buck-boost), and two MAX25605 sequential LED controllers. Additionally, the EV kit has 12 yellow LEDs installed and comes with an acrylic shield to cover the LEDs for eye protection. The board includes mechanical switches to easily demonstrate different sequence settings and modes of operation. Refer to the MAX25611 and the MAX25605 data sheets for detailed information regarding these ICs.

View Details

Features

  • LED Driver, Timing Circuit, Sequencer, LEDs, and LED Cover
  • Demonstrates Dim Up and Dim Down Sequence
  • Sequence Timing Adjustment Potentiometer
  • Toggle Switches to Easily Evaluate Different Modes of Operation
  • Hazard Light Mode
  • No Software or Graphical User Interface (GUI) Required

/en/design/design-tools/ee-sim.html?

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal.

Parameters

Parametric specs for LED Drivers
VIN (V) (min) 4
VIN (V) (max) 60
Max. No. of LEDs 18
# LED Channels 6
LED Configuration Series-Parallel
ILED per Channel (A) (max) 0.75
Dimming Control Resistor Programming
ICC (mA) (max) 5
LED String Volt. (V) (max) 60
Package/Pins TQFN/20
Budgetary
Price (See Notes)
$2.19 @1k

Key Features

 
  • Flexible Dimming Configuration Provides Optimal Performance​ without a Microcontroller or Software
    • Simple Resistor Programming for Sequence Timing and Direction.
    • Hazard Light Applications
    • Sync Pin Allows Sequencing of up to 16 Devices
    • Optional Logarithmic LED Fade
  • Flexible Configuration Allows the Use of the Same Device in Different Applications​
    • One, Two, or Three Series LEDs per Switch
    • Floating Source MOSFETs
  • EMI Reduction
    • Spread-Spectrum Oscillator
    • Slew Rate Control Minimizes LED Current Spikes
  • Protection Features and Package Improve Reliability
    • Single-LED Short, Open, and Open-Trace Detection
    • Thermal Shutdown and Fault Flag
  • Automotive Ready
    • AEC-Q100 Qualified
    • -40°C to +125°C Operating Temperature Range

Applications/Uses

  • Hardware-Based Lighting Animation
  • Sequential Turn Signal Lights

Description

The MAX25605 is a six-channel automotive sequential LED controller. The device implements a sequential turn function or any other sequential light animation without the use of a microcontroller or software. The MAX25605 integrates six cascoded low RDSON n-channel MOSFETs suitable for LED lighting applications up to 750mA. Each switch supports up to three series LEDs per switch. The entire LED string voltage supported is up to 60V. The n-channel MOSFETs are divided into two groups of three, allowing a single device to sequence either one or two strings of LEDs. Integrated gate drivers and level shifters for the switches are supplied by an internal charge-pump regulator, supporting buck-boost and boost-to-battery applications, in addition to ground-referenced LED driver topologies

Sequencing functionality and timing is programmed by connecting resistors to the A0, A1, A2, and CLK inputs. Programming options include: dimming up/down, short LED threshold, multi-device sequence position, dimming frequency, and fade duration. The optional logarithmic fade feature allows for gradually turning the LEDs on or off. The sequence can be disabled by pulling the enable input low. With EN pulled low, the switches are open and the LED driver current flows through the entire LED string. Each switch also integrates single-LED fault detection, asserting a fault flag in case of shorted LEDs, open LEDs, or open wires between the sequencer and the LED string. Additionally, up to 16 devices can be sequenced together through the use of a SYNC input.

The MAX25605 operates over the -40°C to +125°C automotive temperature range and is available in a 20-pin 4mmx4mm side-wettable TQFN and a 20-pin TSSOP package with exposed pad.

Technical Docs

Support & Training

Search our knowledge base for answers to your technical questions.

Filtered Search

Our dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal.