TDK Combines Varistor and Gas Discharge Tube into One Component

TDK Corporation introduced the G series of surge protection components, comprising the G14 (ordering code: B72214G) and the G20 (B72220G). 

Integrating a metal oxide varistor (MOV) and a gas discharge tube (GDT) into a single hybrid design and connecting them in series leverages the strengths of both elements.

This configuration reduces leakage current to virtually zero, extends the lifetime of the whole component, and provides superior surge protection compared to using either element separately in parallel.

These new components are commonly used in power supplies, chargers, appliances, surge protection devices, and communication systems that demand both efficiency and reliability.

Innovation through series hybrid design:

• Zero standby leakage current: With the GDT isolating the MOV during normal operation, leakage currents are virtually eliminated, maximizing efficiency.
• Extended MOV lifetime: The MOV is only engaging when the GDT has fired, drastically reducing stress and aging.
• Reliable surge handling: When fired, the GDT quickly becomes low resistive and acts as the “first line of defense.” Meanwhile, the MOV clamps residual voltages, absorbs remaining energy, and eliminates follow-current to prevent the GDT from reigniting.
• Compact integration: A single hybrid device simplifies design and reduces board space compared to discrete solutions.

The G series is available in two leaded versions: G14 and G20, which refer to MOV disk diameters of 14 mm and 20 mm, respectively. G14 models support AC operating voltages from 50 V to 680 V, while G20 versions extend this range to 750 V. The maximum surge current capability for a single pulse (8/20 µs) is 6,000 A (G14) and 10,000 A (G20), absorbing up to 200 J (G14) or 490 J (G20) of energy. Their operating temperature range is specified as -40 °C to +105 °C.