LPLDD-5A-16V-3CH Laser Diode Driver

About the LPLDD-5A-16V-3CH Laser Diode Driver

LPLDD-5A-16V-3CH medium-power laser diode driver is the smaller 3-channel (55 x 24 mm), lite version of our driver for RGB laser systems with a built-in soft-start feature. Due to high current efficiency, the laser controller is well-suited for high power laser diodes in projectors and RGB laser systems. Each channel can be controlled independently via the analog input of 0 - 5 V. Analog input allows for the modulation of the current flowing through the diode up to 100 kHz. The max current can be set for each channel via a separate potentiometer on the PCB. Functions of each of the controls on the PCB are labeled to make them more intuitive and easy to set.

A dedicated connector is integrated into the driver, offering enhanced modulation bandwidth compared to alternative connectors. This laser controller is provided without a pre-installed heat sink, catering to users who prefer to utilize their own heat sink or optic plate while concurrently offering a notable reduction in price. It represents a fully operational component, readily deployable for integration into laser devices.

The board labels denoting "R," "G," and "B" channels serve as a reference for connecting the laser diodes. It is possible to utilize any channel with any laser diode, offering flexibility in the configuration.

Recommendations and requirements

• All channels are powered by a single common input.
• The minimum diode input voltage should be higher or equal to 7 V, in other situations, it is given by the following formula:
  Vin = 0,3* I + Vd
• Vin - input voltage
• Vd - diode working voltage
• I - operating current

• Although each channel is rated to handle a current of 5 A, it is not typically utilized to its full capacity. If you would like to use more than 6 A total (sum from all channels) it is recommended to solder the wires directly to the board since the connector is rated at 3 A CW per each pin.
• Take great care to avoid short circuits between the + (VCC) of the power supply and -(GND) of the logic input or monitor input, as this can irreparably damage the thin logic GND paths.
• The modulation input can be utilized as a TTL input with logic levels of 0 V and 5 V, or as an analog input. Analog modulation allows adjusting output power by using specific voltage levels (e.g., 2.5 V for 50% output power, 4 V for 80% output power, etc.). This input can also be used as PWM input. The only requirement is that the base frequency of the PWM signal is in the range of 5-20 kHz.
• We recommend the use of power cables with a cross-section of 0.5 mm2.
• Proper cooling of the power MOSFETs should be provided depending on the used laser diodes and PSU. Without cooling, MOSFETs may be damaged and laser diodes may be burned.
• The MOSFET/MOSFETs must be isolated from the heat sink/plate with a silicon pad as well as a plastic sleeve. A short circuit between MOSFET and heat sink/plate can damage the driver and can be dangerous for the laser diode.

Protection

The laser diode power circuit is safeguarded against reversed polarity using a high current Schottky diode with low forward voltage, protecting the laser diode from incorrect voltage connections while minimizing heat loss.

To safeguard the analog input, a 5V1 Zener diode is incorporated to handle voltages exceeding 5 V. However, it is essential to avoid using higher voltages with this input.