Zero Volt Operation with an Electronic Load

Due to the so-called RDS-ON of field effect transistors, electronic loads have a specific and unavoidable minimum internal resistance which causes a certain minimum DC input voltage in order for the load to be able to sink its full rated current.

Below this minimum voltage, the available voltage will decay on a linear scale. However, to be able to perform applications such as testing individual battery cells, for example, a 3.6V lithium battery, the electronic load must operate with a greater range. This is made possible with the support of a laboratory power supply.

This technical note from EA Elektro-Automatik  discusses areas of application, validity, auxiliary power supply requirements, test application setups, and provides a specific application example.

---