TDK's new DC-link film capacitors rated to +135°C

TDK Electronics has introduced the B3272*A/G/T series of DC-link film capacitors, qualified for continuous operation at case temperatures of up to +135°C, with no derating required up to +105°C. The series uses an EPN dielectric, a blend of polypropylene and cyclic olefin copolymer that TDK says has already been proven in its ModCap UHP power capacitors.

The company positions the series for on-board charging units, xEV traction inverters, automotive DC-DC converters, industrial drives and high-end power supplies, where rising power density, confined mounting space and higher ambient temperatures increase thermal and electrical stress on passive components.

Voltage, capacitance and pin variants

The series covers rated DC voltages from 800 to 1200 V and rated capacitance from 1.0 to 60 µF, across five type variants with three lead spacings:

• B32724A: 1.0-12.0 µF, 2-pin, 27.5 mm spacing, case height 19.0-36.5 mm
• B32726A: 2.0-12.0 µF, 2-pin, 37.5 mm spacing, case height 22.0-32.5 mm
• B32726T (low profile): 2.7-9.0 µF, 2-pin, 37.5 mm spacing, case height 15.0-19.0 mm
• B32726G: 6.0-40.0 µF, 4-pin, 37.5 mm spacing, case height 37.0-48.0 mm
• B32728G: 20.0-60.0 µF, 4-pin, 52.5 mm spacing, case height 45.0-50.0 mm

Rated RMS current figures are quoted at +85°C and 10 kHz, ranging from 3.5 to 24.0 A depending on type and capacitance. TDK says the 4-pin G-type variants support low-inductance busbar interfaces and help reduce parasitic loop area in fast-switching inverter stages, while the low-profile T variant targets height-constrained assemblies.

Qualification and design support

The flame-retardant plastic case and epoxy resin sealing comply with UL 94 V-0, and the series is AEC-Q200E qualified and RoHS-compatible. TDK quotes a useful life of 100,000 hours at rated voltage and +85°C. SPICE model libraries and TDK's web-based Capacitor Life And Rating Application (CLARA) tool are available to support device selection and lifetime estimation for the series.