Explore our engineering capabilities across aerospace, automotive, infrastructure, and consumer electronics modules.
In the contemporary global landscape, the procurement of Electronics Manufacturing Services (EMS) and Surface Mount Technology (SMT) has transitioned from simple cost-saving exercises to core tactical partnerships. Modern original equipment manufacturers (OEMs) demand manufacturing systems that not only operate efficiently but also offer extensive resilience against raw material shortages, supply chain blockages, and geopolitical risks. The integration of high-density component architectures, micro-miniaturized form factors, and safety-critical compliance frameworks requires EMS vendors to provide unparalleled domain expertise.
Shenzhen, China remains the global epicenter for electronic product manufacturing. By offering an integrated ecosystem of raw board fabs, active/passive component distribution networks, and advanced engineering talents, China SMT factories deliver a strategic cost-to-quality advantage. In safety-critical areas like aerospace, medical equipment, and automotive, sourcing managers look beyond unit pricing to evaluate overall reliability, supply chain flexibility, and specialized quality assurances.
A benchmark manufacturer bringing 20 years of operational excellence in electronics contract assembly.
Shenzhen STHL is a high-quality provider of electronics manufacturing services (EMS) in China, we serve customers worldwide along the whole industry chain including PCB layout, components sourcing, PCB fabrication, PCBA assembly, cable assembly, box build assembly and comprehensive testing services.
It was established in 2006, with 20 years of experience in electronics contract assembly manufacturing. Currently, STHL has 220+ staff members. Our 10,000 sqm facilities include 7 SMT assembly lines, 2 DIP/THT lines, 2 function testing lines and 2 finished device assembly lines.
At STHL, we provide electronics assembly services for energy power, communications, automotive, medical, consumer electronics, computers & storage, safety & security, commercial and industrial products. Our customers mainly from USA, Germany, Italy, UK, Poland, New Zealand, Argentina, Brazil, Turkey, Korea, Thailand, and the other 90 regions of the world.
As an IATF16949, ISO9001, ISO14001, and ISO13485 certificated electronics assembly manufacturer, we produce products exactly comply with RoHS standard and quality guarantee. Based on our excellent engineering and production capacities in technical areas such as materials analysis & storage, advanced equipment, reliability testing (AOI, X-RAY, ICT test and function test), high effective SMT and THT assembly, we are recognized as a long-term reliable PCBA vendor by more and more customers worldwide. Welcome to visit STHL factory at any time.
High-density electronic packaging demands extreme precision. STHL's engineering pipelines are built around thermal stability, solder paste control, and high-accuracy component placement systems. From micro passive chips like 0201 and 01005 to complex array packages, our line parameters are systematically calibrated to maintain structural joint integrity and prevent electrical defects like head-in-pillow, solder bridging, and component skewing.
We can handle a wide range of advanced components, including:
But our commitment to quality goes beyond component expertise. We utilize advanced inspection techniques, including AOI and X-Ray inspection, to guarantee flawless assembly.
STHL PCBA also excels in Through-Hole Technology (THT) assembly. Our services encompass:
Ensuring efficiency, traceability, and speed-to-market across every phase of your hardware lifecycle.
STHL operates 7 automated PCB assembly lines for both prototype and mass production. Advanced SMT ensures precise component placement and quality. Skilled technicians provide efficient THT assembly and RoHS-compliant lead-free soldering.
STHL PCB fabrication service produces high-quality, reliable printed circuit boards from simple singles to complex multi-layers, from flex PCB to rigid-flex PCB, we use premium materials and controlled processes to meet precise specifications.
STHL offer global electronic component sourcing and supply chain solutions. Our vast supplier network and expertise ensure access to genuine, certified parts, mitigating risks of counterfeits, allocation, and long lead times to secure your production schedule.
With the precision manufacturing of cable assembly components including handles, retention systems, connectors, and shielding in a wide range of materials and finishes, we have performed many successful cable assembly for many customers from various industrial applications.
Making your projects at STHL from SMT assembly to box build assembly is very cost-effective and fast to market. Covering everything from putting a PCBA into the enclosure with all functions testing to a complete product assembly packaged and ready for delivery to your customers, we can supply the full support.
STHL conducts functional testing (FCT) to verify product performance, preventing defects such as circuit issues, missing or incorrect components. This ensures delivered products are stable and fully qualified.
Operating under rigid global oversight to qualify assemblies for aerospace, medical diagnostic, and automotive control systems.
Automotive Grade Quality Systems
Medical Devices Standard
Quality Management Systems
Lead-Free & Green Materials
High reliability starts with component validation. In our raw materials storage, environmental conditions are managed using dry cabinet storage systems, preventing oxidation or moisture absorption on moisture-sensitive devices (MSDs). Our SMT lines use stencil printers with automatic inspect setups to check paste deposition before components are placed, avoiding errors during the mounting stage.
For complex structures, X-Ray imaging is essential. Under standard validation protocols, we verify voiding ratios, solder fillet heights, and micro-cracking hidden beneath high-density array pins. Thermal profiling is continuously updated for each board layout to ensure uniform reflow conditions without overheating sensitive components.
The transition toward electrification, automated driving, high-speed telecommunication networks (5G/6G), and edge-AI controllers continues to drive component density higher. These complex boards require precision printing, placement, and inspection. As packages continue to shrink down to 008004 components, reflow processes must prevent oxidation and tombstones on micro components.
STHL is adapting its manufacturing processes to meet these changes. By using AOI systems driven by AI classification and offline automated X-ray analysis, our QA teams catch defects before final testing. This focus on reliability ensures high-yield performance for mission-critical industrial applications.
Continued product lineup spanning safety controllers, environmental monitors, power storage, and imaging systems.
Answers to technical, logistics, and compliance questions commonly asked by global procurement directors.
STHL uses strict component sourcing methods to manage supply chain risks. We source components through franchise distributors (such as Arrow, Avnet, and Future) or directly from component manufacturers. When using independent suppliers for hard-to-find components, parts must pass rigorous testing. This includes visual checks, marking analyses, and X-ray testing to verify internal dies and leadframes before they go to production.
We manage BGA voiding by adjusting reflow profiles and choosing the right chemistry. Using inline 3D SPI ensures consistent solder paste deposits, while our reflow ovens use nitrogen (N2) environments to lower surface tension and prevent oxidation. We monitor voiding rates using high-definition 2D/3D X-Ray systems, keeping them within IPC-A-610 Class 3 specifications (typically below 10-15% total voiding in critical joints).
Yes. Our PCB fabrication capabilities support multi-layer designs using high-performance substrates like Rogers, Taconic, Nelco, or high-TG FR4. We adjust oven temperatures to match the specific thermal properties of these materials, ensuring clean trace geometries, minimal signal degradation, and strong layer bonding under extreme temperatures.
We use a structured NPI (New Product Introduction) workflow. During prototype assembly, our engineers run DFM (Design for Manufacturing) checks to find potential assembly problems. Once the prototype is verified, we document the process parameters, stencil designs, and thermal profiles. This information is transferred to our high-volume automated lines to ensure consistency during large runs.
Our facility operates under an ESD protection program that matches ANSI/ESD S20.20 standards. SMT lines use anti-static flooring, ionized air fans, grounded workstations, and continuous wrist strap monitors. Components and assemblies are stored and moved in ESD-safe shielded bags or containers to prevent damage from electrostatic discharge.
We work with customers to create custom testing fixtures using pogo-pin interfaces. These test setups simulate actual operating conditions by applying power, inputs, and monitoring outputs. In critical applications, like flight controllers or ADAS units, we use automated testing programs to verify firmware load cycles, sensor readings, and signal paths, ensuring defective boards do not leave the factory.
STHL holds key quality certifications, including IATF 16949 for automotive electronics and ISO 13485 for medical device manufacturing. These standards require strict quality control, detailed documentation, and traceabilities, ensuring our processes meet the requirements of safety-critical industries.
Yes. Our two box-build assembly lines handle mechanical installation, wire routing, final assembly, and packaging. We provide complete backend logistics support, including custom packaging, labeling, and direct shipping to global distribution centers or end customers.
STHL PCBA
