Malvern, Pa. In addition to reducing component count, these positive temperature coefficient (PTC) thermistors from Vishay Intertechnology Inc., can reduce the board space required to implement overload protection in telecommunications applications by up to 65%, according to the company.
The Vishay BCcomponents 2322 673 xxxxx twin vertical surface-mount PTC thermistors integrate two PTC thermistors into a single surface-mount package. The devices are constructed from a ceramic disc and reflow soldered to a lead-frame. This physical construction results in a flat pick-up area of 30 mm², which facilitates automated assembly.
Maximum voltage rating for the devices is 240 V, and components are available in variants with maximum trip times between 1.2 seconds and 4.0 seconds and maximum current ratings ranging from 2.5 A to 4.0 A.
Fully compatible with automated pick-and-place assembly, and suitable for use in lead (Pb)-free soldering processes, the new components also help to reduce assembly time by providing pre-matched pairs of thermistors within the same package. This eliminates the need for resistance matching.
The use of ceramic PTC technology confers high stability, fast response and recovery times, and the ability to sustain several trip cycles. This in turn allows the devices to conform to the more stringent requirements of the ITU K20-21-45 Edition 2003 specification for overvoltage and overcurrent protection for telecommunications equipment.
All of the new devices are rated to function across the industrial temperature range of -40°C to +85°C. In addition to the standard products, Vishay can produce custom versions based on the PTC technology, on request.
For more information, readers can contact Lyle Fette at (972) 871-1852 or visit: www.vishay.com