LPLDD-1A-16V-3CH Laser Diode Driver

About the LPLDD-1A-16V-3CH Laser Diode Driver

LPLDD-1A-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. This driver is a low current version of the 3-channel driver. The device is designed to deliver a maximum output current of 1 A per channel, specifically tailored for lower power laser diodes. Its design aims to ensure the generation of smooth waveforms, rapid rise and fall times, and minimal ripple.

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.

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.