Optimal Soldering Methods for PCB-Component Lead Connections

Optimal Soldering Methods for PCB-Component Lead Connections

日期：2025-05-09    

Optimal Soldering Methods for PCB-Component Lead Connections 

In the PCB manufacturing process, there are two conventional methods for soldering component leads to the circuit board: first, direct soldering of individual leads to the board; second, applying solder paste to the leads before placing the component and board in a high-temperature oven to melt the paste, followed by solidification to complete the joint.

However, both approaches present significant limitations. When dealing with components featuring numerous leads or high pin density, manual soldering becomes operationally challenging, compromising soldering quality. The second method is particularly problematic due to the elevated oven temperatures (typically 300-400°C), which can degrade heat-sensitive elements on the board, adversely affecting product reliability. Substituting these temperature-vulnerable components with heat-resistant alternatives would substantially increase production costs.

Automotive Component PCB Pin Laser Soldering Post-Process Diagram

To address the limitations of conventional PCB lead soldering methods, Songsheng Optoelectronics has developed an automated laser soldering solution that combines:

Laser Solder Paste Automated Soldering Process:

Step 1: Material Loading
Products are placed on customized Tray pallets (pallet specifications are tailored based on product dimensions and throughput requirements, accommodating multiple units per tray; alternatively provided by clients). Component leads are positioned at designated soldering locations on PCBs and secured with specialized welding fixtures. The loaded trays are then mounted on the right-side fixture of the workstation. Initiate the process by activating the feed mechanism.

Step 2: Precision Alignment & Solder Paste Application
The PCB with component leads is servo-positioned to the vision starting point. An integrated height measurement system and CCD vision system autonomously capture and register all soldering positions through image recognition. After completing imaging for all products on the tray, the system advances to the solder paste dispensing station. Solder paste strips are applied perpendicular to the pin array orientation.

Step 3: Laser Soldering & Unloading
The tray with paste-deposited assemblies is servo-transferred to the laser soldering station. High-energy continuous laser irradiation melts the solder paste, forming permanent connections between leads and PCB. Upon completing all soldering operations on the tray, the assemblies are automatically conveyed to the unloading station for removal.

Automatic Laser Solder Wire Welding Proce

Consistent with the solder paste welding process described above, featuring both manual and automatic feeding options.

Step 2: Positioning & Simultaneous Welding
Essentially identical to the solder paste procedure, with the key difference being that solder application and welding are completed simultaneously in a single step.

Step 3: Wire Feeding & Welding

1. Transfer the product-loaded tray to the combined solder application and welding station

2. Precisely control solder wire dispensing volume through software programming

3. The laser instantly melts the solder wire, forming reliable connections      between component leads and PCB

4. Completed assemblies are finally transferred to the manual unloading station

Songsheng Optoelectronics Laser Constant-Temperature Soldering System

Songsheng Optoelectronics Laser Constant-Temperature Soldering System with Real-Time Temperature Feedback consists of a feeding mechanism (dispensing valve [for automatic solder paste application]/wire feeding guide mechanism [for automatic solder wire feeding]), a coaxial CCD positioning system, and a semiconductor laser. The innovative PID online temperature regulation feedback system effectively maintains constant-temperature soldering, featuring real-time high-precision temperature control of the soldering target, ensuring soldering yield and precision. It is particularly suitable for high-precision soldering applications sensitive to temperature, such as micro speakers/motors, connectors, electronic modules, cameras, and more.