Our AC/DC Power Adapters — Desktop & Wall-Mount quality control system

This page provides a detailed explanation of the quality control system for AC/DC power adapters — desktop & wall-mount and switching power supplies. As a manufacturer of AC/DC power adapters — desktop & wall-mount and switching power supplies, we conduct thorough management at our own factory.

What is Quality Control

According to the “JIS Z 8101 Quality Control Terminology,” the definition of quality control is stipulated as follows.

“Quality Control”: A system of methods used to economically produce products or services of a quality that meets buyer requirements. Quality control is sometimes abbreviated as QC. Modern quality control often adopts statistical methods, and is therefore referred to as Statistical Quality Control or Statistical Process Control.

To effectively implement quality control, the participation and cooperation of all company members—from management, supervisors, operators, and across all enterprise activities such as market research, R&D, product planning, design, production preparation, purchasing and outsourcing, manufacturing, inspection, sales, after-service, finance, human resources, and education—is necessary. Such quality control is called company-wide quality control or total quality management.

In other words, quality control is a system that

1. Fully grasps the quality required by customers and society
2. Economically produces products that meet these quality requirements and delivers them to the market
3. Efficiently improves and maintains quality across all business divisions with the aim of achieving customer and societal satisfaction

That is what quality control is about.

Our Quality Control System

Below is an outline of our quality control system.

Regarding “Fully grasping the quality required by customers”

The following initiatives are in place:

• Our Japan office and China factory hold discussions with customers about technical specifications
• Drafting of product specifications
• Evaluation using Engineering Samples (ES) and identification of issues
• Reliability evaluation using Customer Samples (CS) and identification of issues
• Design verification carried out from a third-party perspective by the Quality Assurance Department (QA Dept.), not just the design department
• Implementation of design reviews
• Submission of CS to customers
• Obtaining approval for product specification documents

Regarding “Economically producing products that meet these quality requirements and delivering them to the market”

The following initiatives are in place:

• Incoming inspections for all purchased parts based on ANSI/ASQC Standard Z1.4
• RoHS hazardous substance content inspections for all purchased parts using fluorescent X-ray equipment
• Daily lead content inspections of solder in wave soldering baths using fluorescent X-ray equipment
• Inspection of transformers by disassembling to check number of turns and winding method (loose/tight), insulation tape method and number of wraps
• Inspection of soldering quality for DC cords (plug, USB, core) by disassembling
• Creation of QC process charts and Standard Operating Procedures (SOP) based on Process FMEA, and construction of production lines
• When a defect is detected on the production line, the operator presses an alarm button to alert the line supervisor, who quickly feeds back the defect information to the preceding process
• Before starting and after each two-hour break, line supervisors share the latest defect data and work precautions with the team
• QA department’s In-line Process QC (IPQC) conducts regular patrols to check if operators are working in accordance with SOP, and inspects matching of delivered parts with BOM, soldering iron temperature, torque driver values, and various tool settings
• For shipment inspections, lots are split per pallet and inspections are conducted in accordance with ANSI/ASQC Standard Z1.4 to ensure detailed inspection

Regarding “All departments in the company efficiently improving and maintaining quality to achieve customer and societal satisfaction”

The following initiatives are in place:

• At the beginning of the year, all departments set targets and work toward achievement; management reviews are held monthly to review progress and point out areas for improvement
• Daily quality improvement activities include post-shift discussions among line supervisors and QA to share nonconformance information and prevent recurrence
• For market complaints, QA analyzes the issue—if the cause is process-related, updates SOP and improves jigs/tools; if part-related, provides feedback to part supplier (including process audits); if design-related, incorporates changes into design standards to prevent recurrence

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