Raleigh, N.C. Stackpole Electronics Inc. has developed a broad line of leaded and surface-mount, single and multi-layer varistors for the automotive industry. Designated the AV series, these devices are designed for 12-volt, 24-volt and 42-volt automotive systems.
Providing bi-directional transient voltage protection for sensitive automotive electronics applications including anti-lock brakes, direct ignition, airbag controls and windshield wiper motors, the new AV devices offer high maximum current capabilities and superior ratings for automotive V jump test and load dump energy requirements, said the company.
The multi-layer varistors meet the requirements for automotive circuit protection because they are volumetrically efficient and fast reacting, yet are still able to withstand large amounts of current and energy, said the company.
The chip-style, surface-mount multi-layer AV series is available in 0805 to 3225 case sizes, with single-pulse peak currents from 120 to 2,000 amps (8/20 microsecond waveform) and single-pulse transient energy spikes from 0.3 to 17 joules (10/1000 microsecond waveform). The company said the surface-mount version requires significantly less space and provides greater response times than typical silicon TVS diodes.
In comparison, the through-hole style uses round and square-shaped designs to achieve superior transient energy absorption due to improved internal energy distribution. Depending on the WLD (load dump) requirements, the AV series is available in single layer (for >50 joules) and multi-layer (>50 joules) components, in disc sizes from 6 mm to 40 mm. The AV series offers single-pulse peak current from 400 to 2,000 amps (8/20-microsecond waveform) and single-pulse transient energy spikes from 1.6 to 76 joules (10/1000-microsecond waveform). The company said the through-hole devices offer better electrical characteristics in a much smaller size compared with typical round automotive disc varistors.
Pricing for the surface-mount and through-hole AV series devices is $0.25 and $0.35 each, respectively, in quantities of 1,000.
Stackpole Electronics Inc., 1-919-850-9500, www.seielect.com