MEAN WELL LDD-700H DC-DC Constant Current Step-Down LED Driver

1. Introduction and Features

The MEAN WELL LDD-700H is a highly efficient DC-DC constant current step-down LED driver designed for various LED lighting applications. This driver offers a wide input voltage range and precise current regulation, ensuring stable and reliable performance for your LED setups.

Key features include:

• DC-DC step-down converter for efficient power delivery.
• Constant current output of 700mA.
• Wide input voltage range: 9 - 56VDC.
• Wide output LED string voltage: 2 - 52VDC.
• High efficiency, typically up to 97%.
• Built-in EMI filter, compliant with EN55015 and FCC part15.
• Integrated PWM dimming and ON/OFF control functionality.
• Comprehensive protections: Short circuit and over temperature.
• Cooling achieved through free air convection.
• Fully encapsulated with IP67 level for pin and wire style models.
• Compact size for easy integration.
• Backed by a 3-year warranty.

2. Safety Information

Please read and understand all instructions before installation and use. Failure to follow these instructions may result in electrical shock, fire, or other hazards.

• Qualified Personnel: Installation and servicing should only be performed by qualified personnel.
• Power Disconnection: Always disconnect power to the circuit before installing, servicing, or removing the driver.
• Input Voltage: Ensure the input voltage supplied to the driver is within the specified range (9-56VDC). Exceeding this range can damage the unit.
• Output Load: Connect the LED load correctly to the output terminals. Do not short-circuit the output during operation.
• Ventilation: Ensure adequate air circulation around the driver for proper heat dissipation. Do not cover the unit.
• Environment: Avoid installing the driver in areas with excessive moisture, dust, or extreme temperatures outside the specified operating range.
• Polarity: Observe correct polarity for input and output connections. Incorrect polarity can damage the driver and connected LEDs.

3. Specifications

Detailed electrical and mechanical specifications for the LDD-700H driver.

Note 2: Ripple & Noise are measured at 20MHz of bandwidth by using a 12" twisted pair-wire terminated with a 0.1uF capacitor.

Mechanical Specification and Pin Configuration

The following diagrams illustrate the mechanical dimensions and pin assignments for the LDD-H series drivers. Proper understanding of these configurations is crucial for correct installation.

Image: Mechanical specifications and pin configuration for LDD-H and LDD-HW models. This image details the physical dimensions in millimeters and inches, along with the pin assignments for input, output, and dimming control. For LDD-H, pins 1,2,13,14 are -Vout, 11,12 are +Vout, 22 is PWM DIM, and 23,24 are +Vin. For LDD-HW, specific wire colors are assigned to -Vout (Black), +Vout (Blue), LED- (Yellow), ON/OFF and PWM Dimming (White), and +Vin (Red).

Image: Reflow soldering curve for LDD-HS models and derating curve for LDD-H series. The reflow soldering curve shows temperature profiles for optimal soldering. The derating curve illustrates the maximum permissible load as a function of ambient temperature, indicating that the driver's load capacity decreases at higher temperatures to prevent overheating.

4. Installation and Setup

Follow these steps for proper installation of your LDD-700H LED driver.

4.1 Wiring Connections

Refer to the pin configuration diagram in Section 3 for precise pin assignments. Ensure all connections are secure and observe correct polarity.

• Input Voltage (+Vin, -Vin): Connect your DC power source (9-56VDC) to the +Vin and -Vin terminals. For LDD-H, these are pins 23,24 (+Vin) and pins 1,2,13,14 (-Vin). For LDD-HW, the Red wire is +Vin and Black wire is -Vout (which also serves as the negative input).
• Output to LEDs (+Vout, -Vout): Connect your LED string to the +Vout and -Vout terminals. For LDD-H, pins 11,12 are +Vout and pins 1,2,13,14 are -Vout. For LDD-HW, the Blue wire is +Vout and Yellow wire is LED-.
• PWM Dimming (PWM DIM): Connect your PWM control signal to the PWM DIM pin (pin 22 for LDD-H, White wire for LDD-HW). If dimming is not used, this pin can be left open.

4.2 Mounting

The LDD-700H is designed for free air convection cooling. Ensure that the driver is mounted in a location that allows for adequate airflow. Avoid enclosing the driver in a sealed compartment without proper ventilation. For PCB mounting, refer to the recommended PCB layout provided in the mechanical specification image for optimal thermal performance and signal integrity.

Image: Standard application wiring diagram and efficiency vs. output voltage curves. The standard application diagram shows a typical connection setup for the LDD-H driver with input, output, and dimming connections. The efficiency curves (Fig-1 to Fig-4) illustrate the driver's efficiency across different input voltages and number of LEDs, demonstrating high efficiency across various operating conditions.

5. Operating Instructions

5.1 Powering On

Once all connections are securely made and verified, apply the specified DC input voltage (9-56VDC) to the driver. The connected LEDs should illuminate.

5.2 PWM Dimming Control

The LDD-700H supports PWM dimming for adjusting the brightness of the connected LEDs. Connect a PWM signal source to the PWM DIM pin.

• PWM Signal: A high signal (H) of approximately 5V will turn the output ON, while a low signal (L) of 0V will turn the output OFF.
• Frequency: The recommended PWM dimming frequency range is 100Hz to 1KHz.
• Duty Cycle: The output current is directly proportional to the PWM duty cycle. A 100% duty cycle will result in maximum output current (700mA), while a 0% duty cycle will result in no output current (LEDs off).
• ON/OFF Control: If the PWM DIM pin is left open, the driver will operate at full output. To turn off the output, apply a 0V signal to the PWM DIM pin.

6. Maintenance

The LDD-700H LED driver is designed for long-term, reliable operation with minimal maintenance. However, following these guidelines can help ensure optimal performance:

• Keep Clean: Periodically inspect the driver for any accumulation of dust or debris, especially around ventilation areas. Clean gently with a soft, dry cloth if necessary.
• Environmental Conditions: Ensure the operating environment remains within the specified temperature and humidity ranges. Avoid exposure to corrosive gases or excessive vibration.
• Connection Integrity: Occasionally check all wiring connections to ensure they remain tight and free from corrosion.
• No User-Serviceable Parts: The driver contains no user-serviceable parts. Do not attempt to open or repair the unit, as this will void the warranty.

7. Troubleshooting

If you encounter issues with your LDD-700H driver, refer to the following troubleshooting steps:

• No LED Output:
  • Verify the input voltage is within the 9-56VDC range and correctly connected (+Vin, -Vin).
  • Check all output connections to the LEDs for correct polarity and secure contact.
  • Ensure the LED string voltage is within the 2-52VDC range.
  • If using PWM dimming, ensure the PWM DIM pin is not held at 0V (OFF state) or left floating if ON/OFF control is desired.
  • Check for any short circuits in the LED string or wiring. The driver has short circuit protection, which will shut down the output.
• LEDs Dim or Flicker:
  • If using PWM dimming, verify the PWM signal's frequency (100-1KHz) and duty cycle. An unstable or incorrect PWM signal can cause flickering.
  • Ensure the input voltage is stable and free from excessive ripple.
  • Check for loose connections.
• Driver Overheating:
  • Ensure adequate ventilation around the driver. Remove any obstructions to airflow.
  • Verify that the ambient temperature is within the specified operating range (-40 ~ +85°C).
  • Check the load. While the driver has over-temperature protection, continuous operation at the edge of its thermal limits can reduce lifespan.

If the problem persists after performing these checks, contact MEAN WELL technical support or your local distributor for assistance.

8. Warranty and Support

The MEAN WELL LDD-700H DC-DC Constant Current Step-Down LED Driver comes with a 3-year warranty from the date of purchase. This warranty covers defects in materials and workmanship under normal use and service.

The warranty does not cover damages resulting from:

• Improper installation or wiring.
• Misuse, abuse, or unauthorized modifications.
• Operation outside the specified electrical or environmental limits.
• Natural disasters or other external causes.

For warranty claims, technical support, or further inquiries, please contact your authorized MEAN WELL distributor or visit the official MEAN WELL website for contact information.