Semiconductor relay device

A semiconductor relay device comprising:

• a conversion circuit configured to receive an input signal from outside, and pass a first current to a first node based on the input signal;
• an overheat protection circuit provided between the first node and a second node and configured to short the first node to the second node while a temperature in the semiconductor relay device is higher than a predetermined temperature;
• and
• a transistor having a gate coupled to the first node, wherein
• the overheat protection circuit includes:
• a zener diode having an anode coupled to the second node and a cathode coupled to the first node;
• a resistor coupled between the second node and a third node;
• a number n of diodes that are serially coupled, wherein an anode of a diode at a first end of the n diodes is coupled to the first node, and a cathode of a diode at a second end of the n diodes is coupled to the third node, where n is a natural number larger than or equal to 2;
• and
• a thyristor having an anode coupled to the first node, a cathode coupled to the second node, and a control terminal coupled to the third node.