TT electronics has introduced a comprehensive range of wirewound resistors offering what it claims offers the industry’s highest surge energy ratings from 2W to 7W.
Suitable for a wide range of pulse applications, the WHS series flameproof resistor is aimed, particularly, at designers of power supplies requiring a line input resistor for inrush limiting and protection.
Optimized surge performance derives from the special winding design of these resistors, in which a high-purity ceramic substrate is assembled with interference fit end-caps welded to the terminations. The resistive element is then wound on the substrate and welded to the caps. Its ability to withstand the high surge conditions associated with switch-on, discharge or external surge events results in improved reliability, savings in PCB space and reduced need for additional components.
The WHS2, rated at 2W, is the smallest resistor of its type on the market and provides surge energy ratings of 0.9 to 5.8J, according to the company. Models are available rated 3, 5 and 7W, in resistance values up to 330Ω and taking energy ratings up to 60J. In addition, a 10W model is under development. Moreover, designers have greater flexibility with the additional options of radial, goalpost, lancet and SMD Z-form leads.
All the new resistors benefit from UL94-V0 flameproof protection and operate over a wide -55º to +155ºC temperature range. Delivered in tape-and-reel format as standard, they are RoHS compliant with lead-free terminations.
The full range of WHS resistors is available globally from TT electronics’ distribution channel partners:
Mouser and Premier Farnell