Example of Quickly Solving Peak Current Issues of AC/DC Power Adapters — Desktop & Wall-Mount with Semi-Custom Solutions

The power repeatedly shut down during startup, and the cause was unknown… What was happening with the commercially available third-party AC/DC power adapters — desktop & wall-mount — used by the customer? This article concisely summarizes how we addressed the issue from both procurement and technical perspectives, based on a real case where we resolved a customer's challenges. It offers valuable insights for companies considering peak current countermeasures. We hope you find it helpful.


Case Study: Solving Power Issues Caused by Online-Sourced Products

This article summarizes a real-world case where a customer faced overheating, shutdowns, and compliance issues in a short period due to the use of third-party generic AC/DC power adapters — Desktop & Wall-Mount purchased from online stores. These issues were resolved using our semi-custom power supply.

In addition to essential information for adoption decisions (cost, lead time, compliance, mass production risks), the article also briefly introduces the replacement procedure and key points for compatibility evaluation.

Customer Challenges and Background

During production runs, the customer's equipment experienced repeated voltage drops and recoveries due to inrush current at startup when using existing AC/DC Power Adapters — Desktop & Wall-Mount (third-party DC6V2.8A units). Internal layout changes in these third-party adapters raised concerns over fluctuations in the overcurrent protection (OCP) threshold. The customer approached us to resolve these issues.

Our Solution

Key Points of Our Approach

ItemCurrent SituationNotes/Considerations
Peak Current

4.2A instantaneous (measured)

Need to ensure alignment with OCP threshold

OCP Setting

Third-party product: Estimated 2.8A

A buffer setting helps prevent malfunctions

Response Process

  1. Customer Requirement Hearing

Confirmed symptoms, occurrence timing, and usage environment

  1. Cause Analysis and Real-Unit Measurement

Measured current waveform and estimated overload protection operating point

  1. Design Review and Prototyping

Optimized settings using the UV324 series and developed a semi-custom specification

  1. Evaluation and Verification

Conducted functionality check, safety tests, and long-term operation testing

  1. Integration into Mass Production

Updated BOM, finalized manufacturing procedure, and built quality control system

  1. Customer Report

Shared response results, effectiveness, and future supply structure

 

[Point] Optimized overcurrent protection created a robust power supply utilizing existing series

Based on the hearing,we identified overcurrent protection activation as the cause of power failures. Using ourUV324series, we developed a semi-custom specificationthat prevents protection from activating up to4.2A MAX. This allowed us to offer a solution balancing cost with development speed.

Results After Implementation

  1. Defect symptoms were resolved; no more power drops or restarts occurred
  2. Identifying the root cause secured confidence in both procurement and technical areas
  3. Optimized overload protection ensured stable operation during peak current loads
  4. Semi-custom solution successfully scaled to mass production in a short time
  5. Confirmed continued use policy and established stable supply framework

Customer Feedback

"The defect disappeared, and confirming the root cause brought us great peace of mind. We would like to continue using Unifive products going forward."

─ Development Representative, Wastewater Treatment Equipment Manufacturer

For Customers Facing Similar Challenges

When matching products with adapters, devices that use motors, amplifiers, etc., may experience momentary current surges exceeding the rated value, which could cause operational issues.

If you are using adapters with such devices, please feel free to consult us. We offer advice and propose optimal custom or semi-custom solutions.