This application note describes a new layout method which meets the electrical insulation requirement specified by IEC950 standard.
This document addresses new security rules regarding insulation measurements in telecommunication systems, specifically referencing the IEC950 standard. It describes a test circuit where a 2 kV voltage is applied between lines and ground to ensure current limits are not exceeded.
To comply with these requirements, STMicroelectronics proposes an adapted input/output arrangement for the THBT series. The proposal involves isolating inputs from outputs and connecting only specific ground pins on components with four ground pins to withstand surge currents.
A voltage of 2 kV is applied between the lines and ground.
The current flowing in the test circuit shall not exceed 10 mA.
Only two ground pins are enough to withstand the maximum surge current capability.