A microload is a load that is switched with a circuit current of a few milliamperes. Microloads are used for signal pulses to input to electronic devices such as those used in microcomputers.

1. Switches for Microloads

For a microload, there is not sufficient energy to destroy the film on the contact surfaces that results from oxidation and sulfurization. This makes contact failure a problem.
We recommend the use of switches for microloads that use contact materials that resist the influence of films (e.g., gold) or that use crossbar contacts, which also resist the influence of films.
They are included in the main models of basic switches.

2. Microload Application

To prevent contact failure, confirm the current-voltage application range that is specified for the switch.

  • For example,

    a switch rated for 0.1 A for 30 VDC with a minimum applicable load of 1 mA at 5 VDC would be used within the trapezoidal area.

    The minimum applicable load is the N-level reference value (JIS C5003).
    This level indicates only one random failure caused by unstable contact resistance for every two million operations.

When you use a switch for a microload, confirm that the application conditions are within the application range.
Install CR circuits or other absorption circuits to prevent noise and incorrect pulses due to bouncing and chattering.
For loads that cause inrush current during switching, insert contact protection circuits because the durability of the switch will be reduced.