PCB Services
PCB Assembly Services
SMT, through-hole and mixed-technology assembly with full inspection.
PCB assembly transforms bare circuit boards into functional electronic assemblies by mounting and soldering components according to the bill of materials and assembly drawing. AstroPCB provides surface-mount (SMT), through-hole (THT), and mixed-technology assembly with automated pick-and-place, reflow soldering, wave soldering, selective soldering and manual assembly for specialized components. Assembly services cover prototype through production volumes with turnkey component sourcing, testing and inspection included.
SMT Assembly
Surface-mount technology assembly is the core of modern PCB assembly. Solder paste is deposited on the board pads through a laser-cut stainless steel stencil, components are placed by high-speed pick-and-place machines, and the board passes through a reflow oven where the solder paste melts and forms the solder joints. Modern pick-and-place machines place components at rates of 20,000-60,000 components per hour with placement accuracy of ±25 microns — sufficient for 0201 passives and 0.3 mm pitch BGAs.
Solder paste inspection (SPI) after stencil printing verifies paste volume and alignment on every pad before components are placed. This in-process check catches printing defects before they become assembly defects, reducing rework and improving first-pass yield. After reflow, automated optical inspection verifies component presence, orientation, polarity and solder joint quality.
Through-hole assembly
Through-hole components — connectors, transformers, electrolytic capacitors, power devices with tab leads — are inserted through plated holes and soldered by wave soldering, selective soldering or manual soldering depending on the component mix and board layout. Wave soldering is efficient for boards with many through-hole components on one side. Selective soldering targets specific through-hole components on boards that also carry SMT components on the solder side, avoiding thermal exposure to nearby SMT joints.
Testing and quality
In-circuit test (ICT) verifies individual component values, solder joint integrity and basic circuit connectivity using a bed-of-nails or flying probe fixture. Functional test validates that the assembled board performs its intended function under specified conditions. Boundary scan (JTAG) tests digital ICs and board-level interconnections without physical probe access. X-ray inspection examines BGA, QFN and bottom-terminated component solder joints that are hidden beneath the package body.
Assembly quality is managed through IPC-A-610 workmanship standards. Class 2 (dedicated service electronics) is the default acceptance standard. Class 3 (high-performance electronics) is available for medical, military, aerospace and other reliability-critical products. The quality system tracks defect rates, SPI data, AOI results and test yields to identify process trends and maintain continuous improvement.
Component sourcing
Turnkey assembly includes component procurement from authorized distributors. The BOM review identifies availability, lead time, minimum order quantity and pricing for every line item. Alternate components are proposed for out-of-stock or end-of-life parts, subject to customer approval. Component traceability — from distributor invoice through incoming inspection to placement on a specific board — is maintained for every assembly lot.
Request an assembly quote
Upload Gerber files, BOM (with manufacturer part numbers), centroid file and any test procedures. Specify the quantity, turnkey/consigned preference and delivery target. The engineering team will review and return a quotation.