Low-Resistance, High-Current Reflowable Thermal Protection (RTP) Device

TE Circuit Protection announces the RTP200R060SA device, the latest in the series of Reflowable Thermal Protection (RTP) devices that offer a convenient, cost-effective alternative to typical thermal fuses. RTP devices help protect against thermal-runaway damage caused by MOSFETS, capacitors, ICs, resistors and other power components that can crack and fail.

The new RTP200R060SA device provides a lower 0.6mOhm (typical) series resistance than the initial RTP device offerings, as well as high-voltage capacity (32VDC) and high-current DC-interrupt ratings of 200A at 16VDC. These characteristics make it suitable for automotive applications such as HVAC, ABS, power steering modules, DC/DC converters and PTC heaters. The device also helps protect power components in IT servers, telecom power, LED lighting systems and appliance electronics.

Unlike radial-leaded thermal fuses, which must be installed after reflow, the RTP device allows use of standard surface-mount production methods, obviating the need for special assembly procedures and their associated costs. The RTP device's 200°C open temperature helps prevent false activations, particularly in automotive environments, where a "must not trip" requirement exists for temperatures of 175°C.

To allow it to open at 200°C in the field, the RTP device utilizes a one-time electronic activation process to become thermally sensitive. Before activation, it can withstand three Pb-free solder reflow steps (260°C peak) without opening. Arming can be implemented during system test, or in the field.

"In terms of manufacturing efficiencies, the surface-mount RTP device offers important benefits over radial-leaded thermal fuses," said Faraz Hasan, Global Marketing & Business Development Manager for Appliance/Industrial/Lighting. "Thermal fuses may also be unsuitable for harsh environments. In comparison, the RTP device is resistant to shock, vibration, temperature cycling and humidity exposure, and is tested to meet or exceed some of the strictest automotive AECQ environmental and life-testing requirements."

The RTP device is Pb-free, halogen-free, RoHS compliant and allows for conformal coating.