Glenrothes, Scotland, TT electronics BI Technologies SMT Division has developed a series of planar heaters with ratings up to 50 W for military, computing, telecommunications, medical and commercial applications.
Available in surface mount, through-hole and custom versions, the planar resistive heaters are available in a power rating range of 2 to 50 W. These devices can be used to target heat where it's needed to maintain optimum operating temperatures of electronic systems. The company also noted that the through-hole planar heaters (3 to 50 W) can be placed adjacent to individual modules. "This targets the heat, rather than heating the complete inside of enclosures, making this method of heating much more energy efficient," according to Jim Rieley, sales director for BI Technologies SMT Division.
The company also provides profiled heaters for outdoor computer accessories such as keypads, LCD displays, disk drives, card readers and various drive mechanisms. The planar-screened cermet heaters feature fast heat-up and recovery response characteristics, which ensures temperature stability at the point of use, said the company. "These significantly outperform PTC heaters, whose relatively slow time to temperature and recovery time could, in certain circumstances, result in thermal cycling of the electronics, thereby shortening operational life," stated Rieley.
Thermal measurement components may be placed directly onto the substrate-heating element to provide an accurate interface to the control electronics to deliver precise temperature profiling. Applications include military systems, parking meters, medical equipment, telecom repeaters, external cameras, drive mechanisms and printers.
Printed on ceramic substrates, the heaters are less expensive than most available products, said the company. They are available with resistance values from 0.1Ω to 100 KΩ, with tolerances to ±1%, and temperature coefficient of resistance (TCR) values to ±100 ppm/°C. The operating temperature range is -55°C to 155°C. The maximum operating voltage for the heaters is 250 V.
Most of these products are semi-custom devices. The basic 3-watt heater is priced at approximately $0.35 and the 10-watt heater is priced at about $0.65. The heavy-duty 30-watt version costs around $2.85 each. Evaluation samples are available.
TT electronics BI Technologies SMT Division, +44-1-592-662200, www.bitechnologies.com/power