Despite the automotive sector slowing down in 2020, the long term growth in ADAS is expected to increase significantly, CAAGR 15.5% (2019-2024), according Electronics Supply Report Prismark in June 2020. The polymer automotive grade capacitor represents an opportunity for miniaturization and cost of overall solution reduction. This an important capacitor technology in continuous concerns regarding board space and high volumetric efficiency. KEMET is now expanding the maximum capacitance in the T598 (125ºC) 3528-21 case size to 150 µF 6.3 V.
KEMET Automotive grade products were released to market in 2015. Since then, several extensions have been added to the portfolio. In order to support critical miniaturization, reliability, and high volumetric efficiency ADAS requirements, KEMET is now releasing the EIA3528-21 case size 100 µF and 150 µF 6.3V (See Figure 1).
Figure 1: T598 (125ºC) Polymer Automotive Grade – New CV Extensions
Polymer SMD capacitors are solid state capacitors that demonstrate no wearout mechanism when operated within their recommended guidelines. While they can be operated at full rated voltage, most circuit designers seek a minimum level of assurance in long term reliability, which should be demonstrated with data. A voltage derating can provide the desired level of demonstrated reliability based on industry accepted acceleration models. Since most applications do require long term reliability.
KEMET recommends that designers consider a voltage derating, according the Table 1 maximum steady state voltage. The new extended capacitance 6.3 V rated voltage capacitors are well suitable for usage in 3.3 V voltage line in applications up to 125ºC and in 5 V voltage lines in applications limited to a maximu temperature of 105ºC.
Table 1: Derating T598 (125ºC) and T59(150ºC) – Typical application voltage
The new capacitance offerings are qualified according AEC-Q200 and show electrical stability beyond standard requirements. Figure 2 shows the ESR (equivalent series resistance) performance at 125ºC, 0.67 Ur up to 2,000 hours for the T598 B 3528-21 150 µF 6.3 V with 45 mΩ specification limit. The automotive design and manufacturing process reveals exceptional stability.
Figure 2: Probability Plot – T598 (125ºC) B 150 µF 6.3 V 45 mΩ – Life Test 125ºC/0.67 Ur – up to 2,000 hours – ESR (IL – Initial Specification Limit 45 mΩ, PL – Acceptance criteria post test 2xIL)
In addition to the long term life stability under harsh conditions, the ESR performance in frequency also reveals an extended range at low values, as shown in Figure 3.
Figure 3: Frequency Scan – ESR and Impedance – T598B157M006ATE045 (Green line IL 45 mΩ)
The new capacitance extensions in KEMET Polymer Automotive grade portfolio offer potential solutions to automotive designers where space board saving, high volumetric efficiency/miniturization and reliability are required. Please contact a KEMET sales representative to support you in your actual challenge!
