Manufacturing process of Type-C connector

1. Design and raw material preparation

• Structural design

Design a 24 pin (12+12) layout based on the USB-IF TID certification standard

The shell size complies with the USB Type-C Rev2.1 specification (8.34 × 2.56mm body)

• Material selection

◦ Shell: PBT/PPS engineering plastic (high temperature resistant to 260 ℃)

Terminal: phosphor bronze (C5191/C5210)+nickel plated bottom layer (1-2 μ m)+gold plating (0.5-1 μ m)

◦ Core: LCP liquid crystal polymer (resistant to reflow soldering temperature)

Welding legs: SUS304 stainless steel

2. Precision stamping (terminal manufacturing)

• Process flow

1. Copper strip cutting → High speed punch continuous die stamping (accuracy ± 0.01mm)

2. Molding: Converging and bending to form an elastic contact structure

3. Degreasing cleaning (ultrasonic+alkaline solution)

4. Electroplating treatment:

◾ Pre nickel plating (1.5 μ m) → selective gold plating (0.8 μ m, Vickers hardness 300-400)

◾ Salt spray test for coating ≥ 48 hours

5. Laser detection: Pin spacing tolerance control ± 0.03mm

3. Injection molding

• Shell injection molding

Mold temperature: 120-140 ℃ (PBT material)

Injection pressure: 80-120MPa

Cooling and shaping after ejection (to prevent warping and deformation)

• Core molding

Using LCP material, mold temperature is 150-180 ℃

Infrared detection size after injection molding (with a focus on controlling tongue thickness of 0.6 ± 0.05mm)

4. Assembly process

• Pre assembly

1. Terminal insertion rubber core: using servo pressing equipment (pressure 5-8N/pin)

2. Laser welding fixed terminals and PCB contact pieces

3. Shell closure: Ultrasonic welding (frequency 20kHz, amplitude 50 μ m)

• Key control points

Terminal coplanarity ≤ 0.05mm

◦ Insertion and extraction force control (5-20N, compliant with IEC 60512-13-1)

Waterproof models require adhesive sealing (epoxy resin adhesive, IPX8 rating)

5. Welding and post-processing

SMT mounting

◦ Solder plating: immersion gold/immersion tin (thickness ≥ 3 μ m)

Reflow soldering curve: peak temperature 245-250 ℃ (lead-free process)

DIP plugin

Wave soldering: Tin temperature 260 ± 5 ℃, contact time 3-5 seconds

6. Testing and Inspection

• Electrical testing

Conduct test (four wire system, resistance ≤ 20m Ω)

Insulation impedance (DC500V, ≥ 100M Ω)

• Mechanical testing

◦ Plug and unplug life test (10000 times, attenuation ≤ 15%)

Swing test (load 500g, ± 30 ° 5000 times)

• Environmental testing

High temperature and humidity (85 ℃/85% RH, 1000 hours)

Salt spray test (5% NaCl solution, 48 hours)

7. Packaging and Shipping

Anti static packaging (surface impedance 10 ^ 3-10 ^ 6 Ω)

Barcode traceability system (records production batches/test data)

Compliant with RoHS 2.0/REACH regulations

Key process control points

production processes

parameter

standard

test method

Electroplated gold layer thickness 0.5-1 μ m XRF spectrometer
Injection shrinkage rate ≤ 0.3% 3D imaging instrument
Assembly insertion and extraction force 8-15N digital push-pull force gauge
Welding virtual welding rate ≤ 50ppm X-ray detection

precautions

1. After stamping the terminal, electroplating should be completed within 48 hours to prevent oxidation

2. LCP core needs to be pre dried (120 ℃/4 hours) to avoid bubbles

3. The gold plating process needs to control the cyanide content (≤ 5ppm)

4. The finished product needs to pass USB-IF TID certification testing (such as TD. 4.9 signal integrity)

If further refinement is needed for a certain link (such as high-precision mold design, electroplating process parameters, etc.), special technical documents can be provided.