P1803UALTP

P1803UALTP Application Field and Working Principle

P1803UALTP is a 3-A Fast Recovery Thyristor. It is a silicon-controlled rectifier (SCR), specifically a unidirectional voltage-sensing thyristor, and is mainly used in relay protection and energy control systems for current limitation, surge absorption and overvoltage protection. It is suitable for applications in various control and protection functions, such as electric emergency power off, electric motor and lighting overvoltage protection, etc.

Application Fields

• Home appliances (air conditioners, refrigerators, microwaves, etc.)
• Industrial control (electro-welding, electric furnace, power control consoles, etc.)
• Energy control system (power stations, power assurance systems, etc.)
• Relay protection (surge absorption, overvoltage protection, etc.)

Working Principle

When a small trigger voltage is applied to its gate (G), the P1803UALTP thyristor can be switched on, conducting current between its anode (A) and cathode (K). Also, when the current between A and K reaches a certain value, the thyristor will automatically switch off. The switching characteristic of the P1803UALTP is determined by its turn-on voltage, turn-off voltage, and current ratings.

At turn-on, the gate voltage must be higher than the cathode voltage plus the gate-cathode turn-on voltage (VGT). The gate current (IGT) must also be greater than the gate turn-on current (IGT) for the thyristor to be successfully switched on. Once it is on, the P1803UALTP is able to carry up to 3A of current, and will be able to remain in the on state until the current through the thyristor is reduced to below the turn-off current (ITO). The turn-off voltage is determined by the voltage drop across the load.

The P1803UALTP thyristor is relatively robust and offers a variety of features that make it an attractive choice for many applications. It has a low gate current requirement, high surge capacity, excellent turn-off performance, and a wide operating temperature range. It is also RoHS compliant.