
Testing the insulation resistance of smartphone touchscreens
In the field of consumer electronics , especially in a time when smartphones and other electronic devices are widespread, the insulation resistance of a device (the resistance value measured by applying a defined voltage to the insulating part) is directly related to the safety of the device itself as well as the safety of the user.
In addition to insulation resistance, other properties of the coils in mobile devices must also be precisely tested, including:
- Resistance
- Inductance
- Short circuits between winding layers
- other electrical properties
The resistance measurement must achieve a high degree of accuracy down to the milliohm range .
Tonghui Electronics has developed a comprehensive testing solution for manufacturers of smartphone coils that meets all the important requirements for manufacturing and quality control.

Solution details
Test object:
Single-phase coil
Test requirements:
Resistance:
13 mΩ – 100 mΩ
Inductance:
50 μH – 150 μH
Dielectric strength test:
AC 500 V – 800 V
1 s
0.5 mA
Coil winding test:
800 V
List of instruments
- TH2518A
- TH2829AX-24
- TH2883S4-5
- TH9320S4







