August 2025 Testing Partial Discharge and Isolation Voltage of Digital Isolators with the HT9464M

Project Profile:

In August 2025, EUTTEST Shenzhen provided a manual test version of HT9464M digital isolator certification test system to a customer in Shanghai. This marks the growing demand for digital isolator certification testing in China, and represents the beginning of the country's emphasis on and research and development of new optocoupler replacement products - digital isolators. We took some photos with the customer's consent, and prepared this document "Testing Partial Discharge and Isolation Voltage of Digital Isolator with HT9464M" for the customer, which describes in detail the operation methods and instructions from placing the test samples to obtaining the test results, and provides post instruction service for the customer to use the HT 9464M. This document provides detailed information on the operation and instructions from placing test samples to obtaining test results, providing customers with post instruction services for using the HT 9464M.

Based on the user confidentiality system, this program will not disclose specific user information and will only show relevant pictures and descriptions of the entire test training process.

Imprint:

This example illustration applies to high voltage testersHT 9464M,HT 9464It is also suitable for technical professionals who are preparing to carry out product development of digital isolators.

This example applies to the manual version of the test instructions, when you purchase the automated version which includes a sorter, please contact us for an additional introduction to the operation of the sorter, as with the addition of the sorter the test host will need to communicate and work in co-ordination with the sorter, so the introduction to the test host for the automated version is slightly different to this document.

We can train our customers in Mandarin or English.

Test Sample:

This customer provided the following four packages of digital isolator sample chips.

• SOIC-16 (300mil) - 5 pcs.
• SOIC-8 (300mil) - 4 pcs.
• SOP-16 (150mil) - 5 pcs.
• SOP-16 (150mil) - 5 pcs.

Sample testing process:

Placement of samples:

EUTTEST guides the customer to place the DUT - Digital Isolator onto the HT9464M's test box, which has a customized chip package test fixture built-in by EUTTEST for the customer, and only needs to cover the cover plate after placing the fixture.

Placement of the Sample Under Test-Digital Isolator onto the HT9464M's test box

Modify the HT9464M test configuration:

According to the VDE 0884-17 test waveform requirements shown below

VDE 0884-17 Test waveform requirements for isolation voltages and partial discharges

Combined with the HV and PD limits required by the customer, we need to define the following parameter settings on the front panel of the device:

• HV Test Voltage: 6840V; Minimum Detected Leakage Current: 2.4μA
• PD test voltage: 1880V; minimum detectable PD charge: 0.1pC

Setting HV and PD limits for digital isolator samples

Using our complimentary external keyboard, you can quickly enter a variety of numbers and English characters into the device's host computer software;

HT9464M can be entered using the keypad

Start testing:

Once the parameters are set and the sample is installed, press the "START" button to complete the T1 (isolation voltage) and T2 (partial discharge) tests.

HT9464M starts T1 and T2 testing

Test results:

When the test is completed and use the software to open a test report, we can see from the test report for each chip after the implementation of T1 and T2 test results are "PASS" or "FAIL".

Test Report

One of the sample chips using the SOIC-16 package passed the HV (6840V) and PD (0.1Pc) test requirements, as shown below:

Sample chip in SOIC-16 package passes test

The other sample chip in the same package did not pass T1's HV test. Comparing the top and bottom two images, you can see that HT9464M supports Ramp climbing mode, which simply means that the HV increases from 0 all the way up to 6840V, and if the voltage leakage occurs in the middle of the process, leakage current will be generated, and we can see the sensitive voltage value, which is similar to theFinding Sensitivity Values for Immunity Voltages in EMCSimilar. The test result of our sample shows a sudden avalanche increase in leakage current when the HV increases to 1.3kV, which indicates that this sample cannot pass the HV-6840V certification test requirement at all.

Sample chips that did not pass the HV test

This is the complete digital isolator sample isolation voltage and partial discharge certification test procedure.

Training Summary:

Since the HT9464M training has been completed, the client side also gains the following specialized skills:

• Customers can use the HT9464M alone to perform the complete test process.
• Customers can change the samples of different packages to perform the test process independently.
• Popularize the importance of the "Ramp" mode for the development and design of digital isolators.
• Customers can propose new chip packages
• In the future, customers can install the HT9464M on the chip sorter provided by EUTTEST.