Tough capacitors show their range

Called MLSH Slimpack, the hermetic products are based on Cornell’s non-hermetic Flatpack series, which it has been supplying to military and aerospace customers for more than two decades.

Slimpack capacitors have “no dry-out mechanism and high capacitance retention at low temperatures”, said Cornell, which is why it claim they can replace banks of wet tantalum capacitors.

“MLSH Slimpack, measuring 1.0inch x 1.5inch x 0.5inch [25 x38x13mm] will weigh less and will have more capacitance than a parallel bank of three or more wet tantalum capacitors as at -55°C,” said Cornell. “High capacitance at low temperature is a key requirement for power supplies used in military and aerospace applications. And the technology is expected to have a significantly lower cost than a comparable bank of wet tantalum capacitors.

Since its announcement in June, Cornell has already increased the voltage rating of capacitors available in MLSH Slimpack up to 250Vdc. 5,000 hours life is claimed for nine values of capacitance, from 120 to 3,200µF, with ratings up 250Vdc. “The new high-voltage MLSH Slimpacks eliminate the need for series banking,” said Cornell.

Operation goes as low as -55°C and up to 125°C. The cases are stainless steel and they have a vibration rating of 80gravity. Suppliers include Digi-Key, Mouser and TTI.

Vishay

Vibration resistance was also the aim of Vishay when it created five new series of aluminium capacitors through its BCcomponents operation.
Surface-mount 260 CLA-V, 246 CTI-V, and 250 CRZ-V; and radial 246 RTI-V and 250 RMI-V combine their high-vibration performance with low impedance, high ripple current, and long life for automotive and industrial applications.
The surface mount and radial devices offer vibration resistance up to 30 and 50gravity respectively.

AEC-Q200-qualified (for automotive) capacitors feature impedance down to 1mΩ at 100kHz (for filtering) and ripple current to 3.5A – and 10,000 hour life in both ‘250’ forms. Components range across 150 to 10,000µF and 6.3 to 100V.
The SMD capacitors are offered in six-pin versions and meeting JEDEC J-STD-020 soldering guidelines for severe reflow conditions.

The radial parts have cylindrical aluminium cases with pressure relief insulated with a blue PET sleeve.

“All capacitors are charge- and discharge-proof, so there is no peak current limitation,” said Vishay, adding that the capacitors have non-solid, self-healing electrolytes. Use in smoothing, filtering, and buffering in switch-mode power supplies and dc-dc converters is expected.

All parts work down to -55°C, and maximum temperature is +105 (‘250’ series), 125 (‘246’s) and even 150° (‘260’).

Murata

High temperature operation – at up to 125°C – is the key parameter in a new series of 1210 size (3.2 x 2.5mm) monolithic ceramic capacitors from Murata, and the range includes a 10µF part.

Rather that military and aerospace, Murata has increased operating temperature for emerging networking and telecoms applications.

“With more advanced and multiple functions being incorporated into electronic equipment, the operating temperatures have become higher, and the need for a higher guaranteed operating temperature and larger capacitance in capacitors has grown,” said Murata.

High reliability is still a design goal. “High-reliability monolithic ceramic capacitors are often used in the power supply circuits of network equipment and base stations, and the required capacitance has to date been ensured by using two or more 2.2μF and 4.7μF capacitors,” said Murata. “The 10μF capacitor that we have currently introduced to the market allows the number of required capacitors to be reduced, and helps in making equipment more compact and more reliable.”

The 10µF part is rated at 100V. “The power supply circuits of network equipment and base stations are often used on 48V lines, prompting calls for capacitors with a rated voltage of 100V,” said Murata. “This new monolithic ceramic capacitor is the first of its kind at 1210 size with a guaranteed operating temperature upper limit of 125°C, rated voltage of 100V, and capacitance of 10μF.”

GRM32EC72A106KE05, as the 10μF is known, has X7S characteristics, K (±10%) tolerance, and is 2.5mm thick.

Kemet

Kemet is another company creating high-temperature ceramic capacitors, this time operating up to 200°C for harsh industrial environments, such as down-hole oil exploration, automotive engine compartments, and engine bay avionics.
In EIA 2824, 3040, 3640, and 4540 case sizes, the parts are in the firm’s ‘HV-HT’ multilayer ceramic capacitor product line and follow COG temperature curves. The case sizes allow for up to 150nF, and their characteristics suite them to wide bandgap semiconductor (SiC, GaN) power converters, said Kemet, where there is a trend for increased voltage, frequency, and temperature.

Foreseen applications include critical timing and tuning circuits requiring low loss, as well as high-power pulse, switching and PSU circuits. “These devices exhibit low inductance and ESR with respect to application frequency, allowing for very high ripple current capability,” said the firm.
As ratings go up to 2kV, applications in high voltage coupling, DC blocking, and voltage multiplication are also envisaged.

HV-HT capacitors were developed under Kemet’s ‘base metal electrode’ (BME) dielectric platform, which is 100% Pb-free, RoHS and REACH compliant without exemptions.

Taiyo Yuden

Moving to the other end of multi-layer ceramic capacitors in several ways, Taiyo Yuden has created what it claims is the “the world’s thinnest 0603-size [600×300µm] multilayer ceramic capacitor, achieving a thickness of 0.11mm maximum height value”.
Dubbed JMK063 BJ104ML, the 0.1μF X5R 6.3V part is aimed at power supply decoupling in phones and wearables and is ~27% thinner than its conventional product (0.15mm 0603 JMK063 BJ104MH).

Thickness has been reduced to allow the capacitors to be mounted inside integrated circuit package, or on the back of them, as well as conventional PCB-mounting.