Schede PCB a foro passante a doppia faccia

IO. Panoramica del prodotto

UGPCB Double-Sided Through-Hole PCB Board is a high-performance 2-layer rigid circuito stampato built on an FR-4 glass-epoxy substrate using plated through-hole (PTH) tecnologia. The board measures 86.9 × 73.58 mm with a thickness of 1.0 mm, copper foil thickness of 1/1 OZ (35 μm on both outer and inner layers), and a lead-free hot air solder leveling (Sanguinare) finitura superficiale. The solder mask is green, and the silkscreen legend is white.

A double-sided through-hole PCB (double-sided printed circuit board) features conductive circuitry on both sides of the insulating substrate, with plated through-holes enabling electrical interconnection between the two layers. Compared to single-sided PCBs, double-sided PCBs offer 60%–80% higher routing density and support more complex circuit designs. UGPCB, backed by ISO-certified quality systems and IPC-compliant manufacturing processes, delivers high-quality double-sided through-hole PCBs and turnkey PCB services to electronics manufacturers worldwide.

Ii. Product Definition and Technical Specifications

Per IPC-6012F Specifiche di qualificazione e prestazione per circuiti stampati rigidi (published September 2023), the double-sided through-hole PCB is classified as a rigid printed board with plated through-holes (Tipo 2). Its core feature is the electrical connection between conductors on both sides through copper-plated hole walls. UGPCB manufactures this product in full compliance with IPC-6012F and meets Class 2 performance requirements (dedicated service electronic equipment).

Specifiche chiave:

Iii. Linee guida per la progettazione

3.1 Substrate Material Selection — Engineering Value of FR-4

FR-4 is a flame-retardant grade designation established by the National Electrical Manufacturers Association (NEMA). The letters “FR” stand for flame-retardant, and the number “4” denotes an epoxy resin system reinforced with woven glass fabric. Per IPC-4101 Specification for Base Materials for Rigid and Multilayer Printed Boards, FR-4 Grade A1 represents the core performance tier with optimal mechanical strength, electrical properties, and long-term reliability.

Key Performance Indicators of FR-4 (Fonte: IPC-4101 and industry standards):

• Temperatura di transizione vetrosa (Tg): 130–140°C (standard FR-4)

• Costante dielettrica (Non so) @ 1 GHz: 4.2–4.5

• Fattore di dissipazione (Df) @ 1 GHz: ≤ 0.020

• Punteggio di infiammabilità: UL 94 V-0

• Assorbimento d'acqua (24 ore): ≤ 0.10%

FR-4 remains the predominant substrate material in the PCB industry because it offers an outstanding balance of mechanical strength, isolamento elettrico, stabilità dimensionale, and processability.

3.2 Circuit Design Standards per IPC-2221

Per IPC-2221 Standard generico sulla progettazione di schede stampate, conductor width design must account for current-carrying capacity, temperature rise, e spessore del rame. The IPC-2221 current-carrying capacity formula is:

I = k · ΔT^0.44 · A^0.725

Dove:

• I = Maximum current-carrying capacity (UN)

• k = Empirical constant (0.048 for external layers, 0.024 for internal layers)

• ΔT = Allowable temperature rise (° C.)

• A = Conductor cross-sectional area (milioni²), where A = W × T

UGPCB’s product features a line width of 0.32 mm (ca. 12.6 mil), line spacing of 0.37 mm (ca. 14.6 mil), and copper thickness of 1 OZ (35 μm). For an external layer trace with a 10°C temperature rise:

A = 0.32 mm × 0.035 mm = 0.0112 mm² ≈ 17.36 milioni²

I = 0.048 × 10^0.44 × 17.36^0.725 ≈ 0.048 × 2.75 × 7.82 ≈ 1.03 UN

This conductor width supports approximately 1 A of current, meeting the power and signal transmission needs of most consumer electronics and industrial control equipment. IPC-2221 recommends limiting the maximum temperature rise to 10°C or 20°C to preserve PCB service life.

3.3 Hole Diameter and Aspect Ratio Design

The aspect ratio of a through-hole is a critical metric for evaluating drilling and hole metallization difficulty. The formula is:

Aspect Ratio = Board Thickness / Drilled Hole Diameter

For UGPCB’s product with 1.0 mm board thickness and 0.236 mm minimum hole diameter:

Aspect Ratio = 1.0 / 0.236 ≈ 4.24:1

This aspect ratio is well below the industry-recommended upper limit of 10:1 and the conservative design threshold of 8:1. It indicates low difficulty in drilling and metallization, high yield rates, controlled costs, and assured through-hole reliability.

3.4 Land Pattern Design Reference

Per IPC-7351 Generic Requirements for Surface Mount Design and Land Pattern Standard, land pattern design must ensure adequate solder fillet formation and meet solderability, inspectability, and reworkability requirements. For through-hole components, land diameter is typically recommended at 1.8–2.2 times the hole diameter to ensure sufficient annular ring width.

IV. Principio di funzionamento

The double-sided through-hole PCB operates on three core technologies:

1. Double-Sided Routing — Conductive circuit patterns are etched on both the top and bottom surfaces of the FR-4 insulating substrate, allowing component placement on both sides. This significantly increases circuit density and design flexibility.

2. Plated Through-Hole (PTH) Interconnessione — After drilling, electroless copper deposition and electrolytic copper plating build up a conductive layer on the hole walls. This creates low-resistance, highly reliable electrical connections between the top and bottom layers. Per IPC-6012F Class 2, the minimum average plated copper thickness on hole walls must be ≥ 20 μm.

3. Component Assembly and Soldering — Components are mounted through hole (Tht) or surface mount (SMT) techniques and electrically connected via reflow or wave soldering, producing a fully functional PCBA (Gruppo a circuito stampato) modulo.

V. Classificazione del prodotto

Per the IPC-6012F classification system for rigid printed boards, UGPCB’s product is classified as follows:

By application domain, this product falls into the General Industrial Grade Double-Sided PCB categoria, suitable for consumer electronics, controlli industriali, Attrezzatura di comunicazione, Adattatori di potenza, and other medium-reliability applications.

VI. Composizione materiale

6.1 Substrate — FR-4 Copper-Clad Laminate

FR-4 is a glass-reinforced epoxy laminate composed of electronic-grade woven glass fabric as reinforcement and epoxy resin as the binder, consolidated under high temperature and pressure. Its UL 94 V-0 flammability rating means that in the vertical burn test, the material self-extinguishes within 10 seconds after each of two 10-second flame applications, with no flaming drips that ignite cotton.

6.2 Copper Foil — 1/1 OZ

One ounce (1 OZ) of copper foil has a thickness of 35 μm (1.37 mil). UGPCB uses 1 OZ copper on both outer layers (designated 1/1 OZ), ensuring equal current-carrying capacity and conductivity on both sides.

6.3 Surface Finish — Lead-Free HASL

Lead-Free HASL involves immersing the PCB in molten lead-free solder (typically Sn-Cu, Sn-Cu-Ni, or Sn-Ag-Cu alloys), then using high-pressure hot air knives to level and remove excess solder. This produces a uniform, solderable protective coating on the copper surfaces. The process complies with IPC-6012F requirements and RoHS environmental directives.

6.4 Solder Mask and Legend

• Green Solder Mask — Covers all circuit areas except pads, providing insulation, oxidation protection, and short-circuit prevention.

• White Silkscreen Legend — Identifies component reference designators, polarity markers, board part numbers, and revision levels to facilitate assembly and debugging.

VII. Product Performance

7.1 Prestazioni elettriche

7.2 Mechanical Performance

7.3 Affidabilità

Per IPC-6012F Class 2 Requisiti, the product must pass the following reliability verifications:

• Prova di stress termico (288° C., 10 secondi, no delamination or blistering)

• Plated Through-Hole Copper Adhesion Test (minimum average hole-wall copper thickness ≥ 20 μm)

• Solderability Test

• Electrical Continuity and Insulation Resistance Test

VIII. Product Structure

UGPCB’s double-sided through-hole PCB features a symmetrical 2-layer construction. From top to bottom:

1. Top Legend Layer (White Silkscreen)

2. Top Solder Mask Layer (Green Ink)

3. Top Copper Foil Layer (1 OZ, 35 μm)

4. FR-4 Insulating Substrate (1.0 spessore mm)

5. Bottom Copper Foil Layer (1 OZ, 35 μm)

6. Bottom Solder Mask Layer (Green Ink)

7. Bottom Legend Layer (White Silkscreen)

8. Fori passanti placcati (PTH) — Span the full board thickness with copper-plated hole walls enabling interlayer interconnection

IX. Caratteristiche del prodotto

1. High Routing Density — Double-sided routing delivers 60%–80% higher density than single-sided boards, supporting more complex circuit designs.

2. Highly Reliable Through-Hole Interconnection — Plated through-hole (PTH) technology ensures long-term electrical reliability between layers, with hole-wall copper thickness meeting IPC-6012F Class 2 Requisiti (≥ 20 μm average).

3. Excellent Flame Retardancy — FR-4 substrate meets UL 94 V-0 flammability rating, ensuring safety under abnormal operating conditions.

4. Lead-Free and Environmentally Friendly — Lead-free HASL surface finish complies with RoHS environmental directives.

5. Fine-Pitch Circuit Capability — Minimum line width of 0.32 mm and minimum spacing of 0.37 mm accommodate medium- to high-density circuit designs.

6. Superior Dimensional Stability — FR-4’s low water absorption (≤ 0.10%) ensures minimal dimensional change in humid environments, preserving assembly accuracy.

7. Mature Manufacturing Process — With 1.0 mm board thickness and 0.236 mm minimum hole diameter, the aspect ratio of only 4.24:1 enables mature processes, high yields, and short lead times.

X. Flusso del processo di produzione

UGPCB’s standard double-sided through-hole PCB manufacturing process:

1. Incoming Material Inspection → Verify FR-4 copper-clad laminate thickness, copper foil quality, and visual defects.

2. Taglio → Cut large-format copper-clad laminate to working panel size (86.9 × 73.58 mm).

3. Perforazione → Use high-precision CNC drilling machines to drill all through-holes per the Gerber drill file (minimum diameter 0.236 mm).

4. Plated Through-Hole (PTH) → Deposit a thin copper seed layer on hole walls via electroless copper deposition.

5. Panel Plating → Electrolytically plate copper to build up hole-wall and surface copper to target thickness (1 OZ).

6. Trasferimento del modello → Laminate dry film, expose, and develop to form the circuit pattern resist.

7. Incisione → Etch away unprotected copper to form the final circuit pattern.

8. Stripping → Remove the resist dry film from circuit traces.

9. Applicazione della maschera di saldatura → Apply green solder mask ink, expose, and develop to expose pads.

10. Finitura superficiale → Lead-Free HASL.

11. Legend Printing → Screen-print white silkscreen legend.

12. Instradamento / Taglio a V → CNC routing to final board outline.

13. Test elettrici → Flying probe or fixture testing to verify open/short integrity.

14. Final Quality Control (FQC) → Visual inspection, dimensional sampling, and packaging for shipment.

XI. Scenari di applicazione

UGPCB Double-Sided Through-Hole FR-4 PCB Boards, with their balanced performance and mature processes, are widely used in:

11.1 Elettronica di consumo

• Adattatori e caricabatterie di alimentazione

• Home appliance control boards

• Dispositivi domestici intelligenti

11.2 Controlli industriali

• PLC programmable logic controllers

• Industrial power modules

• Instrumentation and meters

11.3 Attrezzatura di comunicazione

• Routers and switches

• Communication modules

• Signal conversion devices

11.4 Elettronica automobilistica

• On-board chargers

• Moduli di controllo del corpo (non-safety-critical)

• Sistemi di infotainment

11.5 Dispositivi medici

• Patient monitor auxiliary boards

• Attrezzature mediche portatili (Classe 2 applicable)

XII. Product Advantages and Selection Guide

12.1 Why Choose UGPCB Double-Sided Through-Hole PCBs?

• IPC-Compliant Process Control — From material selection to finished goods, full compliance with IPC-6012F, IPC-4101, and other international standards.

• High-Precision Manufacturing — Minimum hole diameter of 0.236 mm and minimum line width of 0.32 mm meet medium- to high-density design requirements.

• Conformità ambientale — Lead-free HASL surface finish complies with RoHS 2.0 directives.

• Proven Reliability — FR-4 substrate has been market-validated for decades with consistent performance.

• Consegna veloce — Standard specifications are stocked with ample raw materials, ensuring reliable lead times.

12.2 Selection Reference

UGPCB Double-Sided Through-Hole PCBs are the ideal choice when your project meets these criteria:

• Moderate circuit complexity that 2 layers can accommodate

• Operating frequency below 1 GHz (FR-4 performs excellently in this range)

• Long-term operating environment not exceeding 120°C

• Cost-sensitive applications demanding high value

XIII. Richiedi un preventivo

UGPCB is committed to delivering high-quality PCB manufacturing and turnkey PCBA services to customers worldwide. Whether you need standard-specification double-sided through-hole PCBs or custom requirements (special board thickness, copper weight, finitura superficiale, Controllo dell'impedenza, ecc.), UGPCB’s expert team provides full support from engineering design to volume production.

Get a Quote Today:

• Submit Gerber files + specifications — receive a quote within 24 ore

• Support from prototype to high-volume production

• Free Design for Manufacturing (DFM) revisione

Contatta UGPCB:
📧 Sales Inquiries: [sales@ugpcb.com]
🌐 Website: [www.ugpcb.com]

XIV. Data Source Declaration

The standards and data cited in this document are sourced from the following authoritative organizations:

1. IPC (Associazione che collega le industrie elettroniche): IPC-6012F Specifiche di qualificazione e prestazione per circuiti stampati rigidi (September 2023); IPC-4101 Specification for Base Materials for Rigid and Multilayer Printed Boards; IPC-2221 Standard generico sulla progettazione di schede stampate; IPC-7351 Generic Requirements for Surface Mount Design and Land Pattern Standard

2. UL (Laboratori sottoscrittori): UL 94 Standard for Tests for Flammability of Plastic Materials for Parts in Devices and Appliances

3. NEMA (National Electrical Manufacturers Association): FR-4 material grade definition

4. Industry Standard Technical Data: FR-4 dielectric constant, fattore di dissipazione, and other material property parameters