TE Circuit Protection's New RTP Devices Offer Reflowable Thermal Protection in Low-Temperature AC and DC Designs
The AC-rated RTP140R060S device features 0.7mOhm (typical) series resistance, high-voltage capacity (250VAC) and high-current AC-interrupt ratings of 80A at 120VAC. This device is useful for helping to protect against damage from over-temperature events in low-temperature AC industrial applications such as lighting dimmers. Because they are embedded in the wall, lighting dimmers may have difficulty dissipating heat, which can lead to thermal events. Moreover, MOSFETs employed in this type of design can fail in resistive mode, generating heat and resulting in a thermal runaway condition. To overcome space and heat challenges, the RTP140R060S device can be installed on the PCB in close proximity to the MOSFET it protects.
The DC-rated RTP140R060SD device helps provide MOSFET protection against thermal events in low-power DC applications such as battery power tools, monitoring electronics and automotive designs. Similar to the AC-rated device, the RTP140R060SD device offers 0.7mOhm (typical) series resistance and a 140°C degree temperature open value that helps prevent false activations. Additionally, the device's high-voltage capacity (32VDC) and high-current DC-interrupt ratings (200A at 16VDC) make it especially well-suited for providing robust thermal protection in DC applications that must maintain high levels of reliability and safety.
TE Circuit Protection's RTP technology utilizes a one-time electronic activation process to become thermally sensitive, allowing the device to open at 140°C in the field. Before activation, an RTP device can withstand up to three Pb-free solder reflow steps (260°C peak) without opening. Arming can be implemented during system test or in the field.
Unlike radial-leaded thermal fuses that must be installed after reflow, the RTP device permits the use of standard surface-mount production methods, obviating the need for special assembly procedures. The device can also be installed on double-sided PCB's.
"The new low-temperature AC- and DC-rated RTP devices are an important enhancement to our RTP portfolio," said Faraz Hasan, TE Circuit Protections Global Marketing & Business Development Manager for Appliance/Industrial/Lighting. "The new devices are available in the same form factor as our existing RTP200 devices yet activate at even lower temperatures."
The RTP devices are Pb-free and halogen-free, RoHS compliant and allow for conformal coating. UL testing is currently underway.