TDK has qualified its new B3272*A/G/T series of DC-link film capacitors for continuous operation at case temperatures of up to +135 °C, with no derating required up to +105 °C. The company positions the parts at automotive and industrial power electronics where under-hood temperatures keep climbing — xEV traction inverters, on-board chargers, automotive DC-DC converters, industrial drives and high-end power supplies.

The thermal gain comes from the dielectric. TDK uses its EPN material, a blend of polypropylene (PP) and cyclic olefin copolymer (COC), in the new series. The same dielectric already ships in the company's ModCap UHP power capacitors. According to TDK, EPN gives DC-link designs for demanding automotive and industrial applications greater thermal headroom than conventional PP film alone.

Standard polypropylene film capacitors typically constrain inverter layout because engineers must either derate capacitance and voltage at high temperature or route cooling to keep the capacitor bank cooler than the surrounding silicon. A 135 °C rating with full performance to 105 °C relaxes that constraint, which matters in traction inverters where the DC-link bank sits close to IGBT or SiC power stages.

The series spans five case types with rated voltages from 800 V to 1200 V and rated capacitance from 1.0 µF to 60 µF:

Type	Rated voltage VR [V]	Rated capacitance CR [µF]	IRMS,max (+85 °C, 10 kHz) [A]	Pins	Lead spacing [mm]	Case height [mm]
B32724A	800 … 1200	1.0 … 12.0	3.5 … 13.5	2	27.5	19.0 … 36.5
B32726A	800 … 1200	2.0 … 12.0	4.3 … 10.0	2	37.5	22.0 … 32.5
B32726T	800 … 1200	2.7 … 9.0	5.2 … 8.0	2	37.5	15.0 … 19.0 (low profile)
B32726G	800 … 1200	6.0 … 40.0	9.0 … 24.0	4	37.5	37.0 … 48.0
B32728G	800 … 1200	20.0 … 60.0	16.5 … 24.0	4	52.5	45.0 … 50.0

The lineup covers several mechanical variants. Two-pin versions suit conventional through-hole layouts; four-pin versions (B32726G, B32728G) improve mechanical stability and current distribution in high-ripple applications. The B32726T offers a low-profile case of 15.0 to 19.0 mm for designs with tight height budgets.

Beyond the temperature rating, TDK lists a high CV product in a compact footprint, good self-healing properties, overvoltage capability, and low losses combined with high current capability — the IRMS,max figures reach 24 A at +85 °C and 10 kHz across the range. The company specifies a useful life of 100,000 hours at rated voltage and +85 °C, a figure that directly addresses lifetime requirements in automotive qualification programs. The parts carry AEC-Q200E qualification and are RoHS-compatible.

For design-in support, TDK supplies SPICE model libraries for the B3272*A/G/T series along with its web-based Capacitor Life And Rating Application (CLARA) tool, which lets engineers estimate capacitor lifetime under application-specific thermal and electrical stress.

With xEV platforms moving to 800 V bus architectures and higher-power density invertors, the 800 V to 1200 V voltage range of the series aligns TDK's film capacitor portfolio with the current generation of SiC-based traction designs, where the company expects dielectric thermal headroom to decide how tightly capacitor banks can be packed next to power semiconductors.