6 Layer Immersion Gold PCB Servo Driver Board FR4 TG170 Material

Product Description:

1. High-Tg Substrate & Thick Copper: Thermal Management Servo drives generate significant heat during operation. High-Tg Material: Tg ≥150°C (≥170°C recommended, e.g., Sunlord S1130) to prevent deformation/softening at high temperatures. Thick Copper: 2oz–3oz copper for main current loops (power transistors, motor drive lines). Compared to 1oz copper, 2oz copper increases heat dissipation area by ≈65% and reduces pad temperature by ≈35°C.

2. ENIG Process Control: Solderability & Reliability ENIG provides flat pads and good conductivity; precise control is critical. Nickel Layer: Temperature 82–88°C, pH 4.6–5.2. Deviation causes uneven crystallization, poor adhesion, and "black pad" defects. Gold Layer Thickness: 0.1–0.5μm recommended. Excessive gold causes "gold embrittlement" and cracks after reflow. Adhesion: Proper cleaning and micro-etching before ENIG ensure nickel-copper adhesion, surviving multiple reflow cycles without blistering or peeling.

3. Precision Circuitry & Impedance Control: Signal Integrity Servo drives integrate PWM, encoder feedback, and other high-precision signals. Line Width/Spacing: LDI technology for high-density areas, line width tolerance ≤±15μm. Impedance Matching: 50Ω single-ended / 100Ω differential for high-speed signals (encoder, communication interfaces), tolerance ≤±10% to prevent reflection and distortion. Length Matching & Isolation: Length matching for critical signals; strict physical isolation between high-current power lines and low-level control signals with ground isolation bands to prevent crosstalk.