Dimensions and Installation

Unit: mm

Panel Wiring

From left to right:

Power Connector: 3.81 × 2P mm connector. Connector model: WJ15EDGRC-3.81-2P. DC 5–6 V, 3 A. Use a low-ripple regulated power supply to reduce the overall system noise.

Recommended Connector:

Communication Connector: S06B-PASK-2(LF)(SN)

Serial communication: 115200 bps baud rate, 8 data bits, 1 stop bit, no parity; 3.3 V TTL level.

A jumper can be used to short GND and RX, allowing the system to start driving the laser at the preset internal current. Please make sure all parameters have been fully configured before using this function.

M1 and M2 are auxiliary connection ports. The internal connectors can be used to directly connect to the laser pins.

Recommended Connector:

COM LED: Communication indicator. The LED lights up red when GND and RX are short-circuited.

SYS LED: System status indicator. The LED lights up yellow when the laser is not installed or when the laser temperature has not stabilized at the set value. It lights up green when the laser temperature has stabilized. It lights up red when the internal drive current is enabled.

INPUT: SMB connector. Connector model: 73100-0103. Input voltage: 0–2.5 V. Input frequency: 0–20 MHz.

Internal Wiring

Before connecting the laser, carefully refer to the laser manufacturer’s manual to verify the pinout of the corresponding connector and the wiring on the circuit board, and ensure that the laser is compatible with the current pin configuration. Applying power with an incorrect pinout may damage the laser.

The negative power input of the module, the base plate, and the negative terminal of the NTC are all connected to ground. The positive and negative terminals of the drive output are not connected to ground. Special attention is required if any functional pin of the laser to be installed is connected to ground (i.e., connected to the laser housing).

If any functional pin of the laser is connected to ground (e.g., the positive terminal of the laser is grounded), a piece of adhesive thermal conductive silicone pad must be placed between the laser and the bottom housing. Metal screws must not be used to secure the laser, so as to electrically isolate the laser housing from the bottom housing. If you are unsure about the grounding configuration, please consult the sales engineer. Incorrect grounding may cause the module to malfunction or even damage the laser.

Caution

! When the driver is used with a laser whose functional pin is connected to the housing (e.g., NEL lasers, where the positive terminal is commonly connected to the housing), the laser housing must be electrically isolated from the base. Place a layer of thermal conductive silicone pad beneath the laser, and do not use metal screws to secure the laser.

! The positive drive terminal of the NEG-type laser driver is connected to ground and the chassis, and can be used with lasers whose positive terminal is connected to the housing.

! The laser current range must be set using shorting jumpers (jumper caps) at P3 and P10. A mismatch between the two settings will cause a discrepancy between the system’s self-identification and the actual current, which may result in damage to the laser.

! It is recommended to first connect an LED or an inexpensive red laser to test whether the current settings are operating properly.

! Laser temperature oscillation indicates that the temperature-control PID parameters are not properly configured. The command for adjusting the temperature-control parameters is tecp kp kI kd. The new settings take effect immediately after the command is sent. Observe the temperature response in terms of accuracy and speed, and adjust the parameters until satisfactory performance is achieved. After adjustment is complete, use the save command to save the settings.

! The module does not have a power switch. The temperature-control function starts operating immediately after the power supply is connected, while the laser current source does not start automatically. The green indicator indicates that the temperature has stabilized. Short-circuit RX and GND using a jumper cap to enable the current source. This function should only be used after all parameters have been fully configured.

Jumper Configuration

Before powering on the module, the circuit parameters must be adjusted to match the laser being installed. The parameters are configured using the jumpers and DIP switches on the circuit board. All adjustments must be performed with the power disconnected.

Set the maximum drive current of the LDRVMLN to a value equal to or slightly higher than the maximum allowable current of the laser. Setting the drive current too high will increase the risk of damaging the laser. The drive current is set using the P3 and P10 jumpers on the circuit board.

The jumper configuration for the standard driver is as follows:

! The P3 and P10 jumpers must be configured identically; otherwise, the device will not operate properly. All operations must be performed with the power disconnected.

The jumper configuration for the low-current VCSEL driver is as follows:

The jumper configuration for the NEG-type driver with the positive terminal connected to ground is as follows:

! If the laser has a built-in voltage-divider resistor, it is recommended to avoid using this resistor whenever possible, as it may result in insufficient external drive voltage and cause the laser to operate under an undervoltage condition.

Operation

Analog Signal Input

The INPUT connector on the rear panel of the device is used to receive external input signals. When the internal bias signal is disabled, the equivalent circuit is shown below.

The driving current of the laser is:

I_Laser = (V1/1.25V) x I_max

I_max=149mA or 378mA

When the internal signal is turned on, the equivalent circuit is as follows:

If only internal signals are used, all connections on the INPUT interface should be disconnected. If you want to use internal and external signals at the same time, please calculate the final effect by yourself according to the above equivalent circuit.

I/O Control

The RX pin can be used as an I/O port. Connecting RX to GND enables the module to start operating using the stored settings.

The recommended circuit is shown below:

Communication Modules

A variety of communication interface modules are available for selection and customization, converting the TTL-level signals of the LDRVMLN to interfaces better suited to the requirements of the installation environment.

USB Module

The module connects to the LDRVMLN through dedicated communication and power interfaces and to a computer via a USB Type-C interface. It uses an FT232RL converter chip, which requires driver installation on the computer. An automatic power switching circuit switches between USB Type-C and the power adapter.

(Due to the 500 mA current limit of the computer's USB port, insufficient power may cause unstable operation. USB Type-C power alone is recommended only for debugging, with the laser current below 150 mA and the temperature setting above 10°C.)

PC Control Interface

Replace the instrument cover, connect the controller to the power supply, and connect the computer with USB cable. Press power button ① to turn on the instrument. WIN7 and above system will prompt to install USB driver automatically. Please download the corresponding driver in http://www.ftdichip.com/Drivers/VCP.htm when using other systems or being unable to connect to the Internet. After the driver is installed, the virtual serial device will appear in the Device Manager.

Open the special software on the computer, as shown in the figure below:

Find the corresponding virtual serial port in Communication Port, if not, click Refresh button. Click the Connect button, the console will light up after normal handshake, and read the current set value of the controller. Enter the required working temperature at LD Temp Setpoint, and click Set Temperature setting. Start slider bar sets the constant working current value, and Limit slider bar sets the maximum limiting current. Click Set Parameters below to send the parameters to the instrument. Click Save All Settings to save all parameters in the instrument.

Click Run:DC to start the laser with the set current value. The Limit slider is used to protect the laser, and can also limit the current under external input,Please set it to the maximum working current in the laser parameter table.

Before starting the laser , please carefully check whether the parameters are within the allowable working range of the laser!

Communication Instructions

A dedicated conversion cable connects the circuit board to the USB or serial port of the computer. The USB converter uses FT232R chip to simulate serial port, and the system above WIN7 will automatically install the driver on the network. Please download the corresponding driver in http://www.ftdichip.com/Drivers/VCP.htm when other systems are not connected to the Internet. After the driver is installed, a new serial device will appear in the "Device Manager", and the default communication rate is 115200bps. Parameters are changed by receiving serial commands in ASCII format, and the commands end with Backspace.

The following describes the communication method with PuTTY as an example. After opening PuTTY, select Serial for connection, enter the same port number as in Device Manager, enter 115200 in Speed, click Open to open the black interactive port, and enter relevant instructions through the keyboard (the Backspace key is invalid). After entering the command correctly, the system will prompt to set the result, and the error will return the error message.

The computer is the main control terminal (upper computer) and sends string commands. Start a line of commands with ":" as the starter, and end a line with Enter (\r\n),The lower computer returns information after executing it. All the following functions can be accessed through supporting software,it is suggested that after setting up with supporting LDPD software and obtaining the correct waveform, click save to save the parameters to the lower computer, and then transfer them to other clients for control.

Operation mode is as follows:

Parameter Setting: