Protect your circuit from noise and surges! Introducing PhotoMOS (semiconductor relay) with protection function

PhotoMOS semiconductor relays provided by Panasonic have more than 400 product numbers and are used in a variety of applications. In this article, we introduce our company's original PhotoMOS with protection function.

PhotoMOS (semiconductor relay) – a component that lies concealed inside industrial and automotive devices (Vol.1)

What are the protection function and its benefit?

• Protects the circuit from overcurrent
• The protection function built into PhotoMOS protects PhotoMOS itself and the circuits after PhotoMOS from unexpected overcurrent.
• Can be used repeatedly, for example, a fuse can be used only once, but PhotoMOS can be used repeatedly.

In what applications and situations are the protection function useful?

To protect circuits from external noise, surge current, and overcurrent caused by miswiring, the protection function is useful in a wide range of applications such as measurement and inspection equipment, production equipment, robots, and communication equipment. The following are typical examples.

Case 1. Inspection equipment for parts (Application: Surge protection from outside)

Traditionally, poly switches have been used to protect against surges from the outside. However, by adopting PhotoMOS with a protection function, which has a faster response time, the safety of the equipment has increased.

Case 2. Controller I/O section of production equipment (Application: Countermeasure against incorrect wiring)

Peripheral parts were broken every time a worker of the factory misconnected the wiring of the production equipment. However, we were able to prevent misconnection by adopting PhotoMOS with short circuit protection function.

Customer Feedback:

Each time the output side was short-circuited, the board had to be replaced.

The use of short-circuit protection type contributes to reducing running costs.

Panasonic offers the following three types of PhotoMOS:

• With Current Limit Function
• Latch Type with Short Circuit Protection
• Non-Latch Type with Short Circuit Protection

Maximum absolute rating (measuring conditions: ambient temperature 25 °C)

We hope that our lineup can be considered according to our customer's application and circuit configuration. For the Protected PhotoMOS, please review the Cautions for Use.

Related Articles:

• Application Note – PhotoMOS® with Protection Circuits
• PhotoMOS (semiconductor relay) – a component that lies concealed inside industrial and automotive devices (Vol. 1)
• PhotoMOS (semiconductor relay) – a component of great importance that lies concealed inside industrial equipment and automotive devices (Vol. 2)