TDK's new L860 NTC thermior chip can be embedded directly into the power module and used for sintering and AI heavy wire bonding. Its properties correspond to the ordinary MELF-R/T curve, with R100 being 493 ohm. Lead-free chips are suitable for a wide temperature range from -55C to +175C, with sizes of 1.6mm x 1.6mm x 0.5mm.
For electric bonding, the product is mounted on the bottom and has a Ni/Ag thin film electrode on the DCB board of the power module for sintering. Unlike traditional SMD NTC chips, lead-free NTC chips are mounted horizontally. In contrast, the upper electrode includes a Ni/Au thin film electrode for aluminum wire bonding. No welding process is required.
The efficiency of a power module is usually highest near its power limit; However, precise temperature control is critical to operating within these limits. Typical operating temperatures are in the 100C range, but may rise slightly to 175C. Compared to other technologies, the solution demonstrates excellent thermal coupling between the NTC chip and the power module, resulting in extremely short response times and high precision temperature measurement and control.
Therefore, the device is very suitable for integration into IGBT and IPM modules.
