VCAS06LC18X500DP Circuit Protection

TVS – Varistors, MOVs

The VCAS06LC18X500DP is a voltage-dependent varistor for peak energy or voltage transient suppression particularly suitable for consumer electronics, automotive, communications and industrial applications.

Application field

VCAS06LC18X500DP varistors can be widely used in many fields where AC surges, DC transients and electrostatic discharge (ESD) protection is needed. These range from consumer electronics, automotive, communications and industrial applications, such as overvoltage protection of power MOS transistors, inductive loads, small motor drives, relays, contactors, over-temperature sensors and light dimmers.

In consumer electronics like smart phones, tablets, laptops and gaming consoles, VCAS06LC18X500DP can be used to protect power Line EMI filters, ESD protection of PCBs, mechatronics and small appliances, so as to avoid catastrophic overvoltage caused by spark discharges, lightning, power surges and ESD.

For automotive applications, VCAS06LC18X500DP is useful in protecting from electrical short circuits and ESD related to airbag launches, short circuit protection and EMI Filters for ECU and control systems and battery isolation.

In communication systems, such as LAN, HDMI/DVI sockets, coaxial interfaces and window transceivers, VCAS06LC18X500DP can be used as a specialized type of surge protector.

Working Principle

The working principle of the VCAS06LC18X500DP relies on its voltage-dependent characteristic, which causes the varistor voltage to increase with the applied voltage, thus limiting the peak voltage reaching the protected device. This characteristic is produced by a combination of PTC ceramic and zinc oxide, thus forming varistors.

Once the varistor voltage is reached, the varistor device will conduct a large current proportional to the input voltage, thus providing a typical diverting effect that transfers the surge from the protected circuit. Depending on the type of application, the varistor can be configured in several ways to optimize the protection provided.

In applications such as ESD protection, the varistor can be used to limit transient peaks that generate huge current pulses, as the varistor will quickly reduce the current amplitude with its disruptive effect.

In surge protection applications, the VCAS06LC18X500DP varistor can be connected in a series or parallel arrangement, making it suitable for multiple protection strategies, while static discharge can be controlled by connecting it in series with a resistor.

Finally, the VCAS06LC18X500DP also offers low leakage current and low clamp voltage, making it suited for sensitive applications.