MLS3535A Constant current LED driver IC SOP-8

MLS3535A Constant Current LED Driver IC SOP-8 is a highly efficient and accurate integrated circuit designed specifically for driving strings of high-brightness LEDs. This versatile controller operates as a linear constant current driver, providing a fixed current output essential for maintaining uniform brightness and extending the lifespan of the connected LEDs, regardless of minor fluctuations in the supply voltage. Consequently, the MLS3535A simplifies circuit design by eliminating the need for bulky inductors and complex feedback loops often required by switching regulators. Furthermore, its small SOP-8 package and built-in protection features make it an ideal choice for compact, reliable, and cost-sensitive lighting products. Engineers commonly use this IC in battery-powered applications and AC/DC lighting systems requiring precise current control.

Key Features:

• High Current Accuracy: Delivers superior constant current accuracy, typically within ±5%, ensuring highly consistent LED luminous intensity across units.
• Adjustable Current Output: Users can easily set the output current from 10 mA up to 150 mA using a single external current-sensing resistor (R_SET).
• Thermal Regulation: Features integrated over-temperature protection that automatically reduces the output current when the junction temperature exceeds a preset limit, thereby protecting the IC and the LEDs.
• Wide Input Voltage Range: Supports a broad input voltage range, enabling compatibility with various single or multiple cell battery configurations and regulated power sources.
• No External Inductors Required: Operates as a linear driver, simplifying the Bill of Materials (BOM) and minimizing electromagnetic interference (EMI).

Technical Specifications:

• Topology: Linear Constant Current Regulator
• Maximum Output Current (I_OUT): Up to 150 mA
• Input Voltage Range (V_IN): Typically 2.8 V to 6.0 V (Check datasheet for specific limits)
• Dropout Voltage (V_DO): Low voltage drop, typically 100 mV to 300 mV, maximizing efficiency for low V_IN applications.
• Current Accuracy: ±5% typical
• Protection: Over-Temperature Protection (OTP)
• Switching Frequency: Not applicable (Linear Regulator)

Mechanical Specifications:

• Package Type: SOP-8 (Small Outline Package, 8-Pin)
• Mounting: Surface Mount Technology (SMT)
• Lead Finish: Lead-Free (Pb-Free)
• Thermal Dissipation: Uses exposed pad or power pins for heat sinking through the PCB copper pour.

Dimensions:

• Body Length: ≈ 4.9 mm
• Body Width: ≈ 3.9 mm
• Height: ≈ 1.5 mm
• Pitch (Between adjacent pins): 1.27 mm (0.05 inch)

Pinout and Wiring:

• VCC (Power Supply): Connect to the input supply voltage (V_IN).
• GND (Ground): Connect to the system ground.
• SET (Current Set): Connects to one end of the external current-sensing resistor (R_SET); the other end connects to GND.
• OUT (Current Output): Connects to the cathode (negative side) of the LED string.
• EN (Enable): Logic input pin (Active High). Drive high to enable the driver; drive low for shutdown, reducing power consumption.
• Wiring Note: Always place the R_SET resistor and bypass capacitors as close as possible to the IC pins to ensure stable operation and accurate current setting.

Datasheet Reference:

• Download MLS3535A Constant Current LED Driver Datasheet

Commonly Used in:

• Portable Lighting: Essential driver component in flashlights, headlamps, and battery-operated emergency lights.
• Decorative Lighting: Used extensively in LED strip lighting, accent lighting, and small display backlighting.
• Signage and Displays: Providing reliable current for individual segments or clusters in LED signs and indicator arrays.

Applications:

• Li-Ion/Li-Polymer Driven Lights: Maximizing LED lifespan in single-cell battery applications.
• General Purpose LED Drive: Serving as the main driver for low to medium-power LED modules in commercial products.
• Indicator/Status Lights: Ensuring consistent brightness for panel indicators and status LEDs.

Equivalent Models:

• CL333 (Chip-Rail): A linear LED driver with adjustable current, often used as a direct or functional alternative to the MLS3535A.
• AP5724 (Diodes Inc.): A high-current, adjustable constant current LED driver, however, verify pin-to-pin compatibility before replacement.
• JW3301 (Joulwatt): Another comparable SOT/SOP packaged linear LED driver that offers similar current setting capabilities.

Package Includes:

• 1 x MLS3535A Constant Current LED Driver IC SOP-8