RNU1A100MDS1 – The Benefits of MLCC Capacitors Part I

MicroCrystal RV-8803 – A Really Accurate RTC June 17, 2019- RTC chips traditionally were the domain of Maxim and NXP. Switzerland-based MicroCrystal recently made quite a buzz with its RV-8803, which offers simple integration, an I2C interface and extreme accuracy. Let us start out by looking at a system overview. Figure one shows how this I2C RTC is made up internally – interested observers note […]
Analog Devices’ LTM2887 – If a Digital Bus Needs Galvanic Isolation June 15, 2019- In theory, digital buses are intended to connect things to one another. Sadly, one sometimes wants but a logical connection – in many cases, galvanic isolation helps out. Should you ever feel like isolating very fast buses, definitely give the LTM2887 a chance. From a technical point of view, Linear Technologies attempt at entering the […]
AVAGO APDS-9008 or APDS-9005-020 – Keeping an Eye on Ambient Light June 14, 2019- Recent times saw quite a bit of interest for part numbers such as the APDS-9008 or APDS-9005-020 – they are a very interesting type of ambient light sensor. One of the oldest questions in regards to light sensors involves their spectral sensitivity. If a part is to output but one voltage level, the conversion between […]
STMicroelectronics’ LIS2DH12 – Low Power Motion Sensing June 12, 2019- Apple’s iPhone introduced gyroscopic sensors to a wider range – before that, accelerometers were not commonly found in consumer hardware. STM sells excellent parts which, however, get little media attention – time to take a look at the LIS2DH12. Integrating the part into your circuit as an MPU6500 alternative or MPU9500 alternative is not difficult. […]
Panasonic AMG8833 – FLIR for cheap June 7, 2019- FLIR made infrared thermal sensors cool – sadly, their parts are all but cheap (and suffer from export control problems). Panasonic’s Grid-EYE family is a low-resolution alternative which comes at significantly lower cost. From a technical point of view, Panasonic’s image sensor could not be simpler. We are looking at an 8×8 sensor with an […]
DipTronics DTS-62R-V – Small Switch, Very Big (and Very Cheap) June 5, 2019- When yours truly was but a lowly cadet, various US manufacturers produced (pricey but quite reliable) switches. Chinese vendors recently started to catch up – seeing the DTS-62R-V top our customer interest list shows that the run stage of the crawl-walk-run cycle is reached. DipTronics has been around the Asian switch market for ages, exhibiting […]

Casual observation would claim that the main job of a parts search engine like OEMsecrets involves…

Casual observation would claim that the main job of a parts search engine like OEMsecrets involves finding cheaper sources for expensive parts. Recently, relatively low-priced MLCC capacitors have taken the lead in terms of search interest – let us tell you what this means for your daily work as a designer…

First of all…

Electrolytic capacitors are not the most desirable of products; they are heavy, large, and tend to fail early. Just a quick look at the various test equipment repair forums returns stories about expensive pieces of gear which croaked because some electrolytic capacitor decided to belch out it’s electrolyte.

Some years ago, a designer at a third-class German electronics trade show introduced the idea of trying to go electrolyte capacitor free. This can be achieved in two ways; firstly, by replacing classics such as the LM2576 with a higher frequency part such as the ACT4065 – they are not only cheaper, but also permit the use of smaller coils and smaller filtering capacitors. Remaining filtering capacitors which are still required are then chosen from MLCC families, paralleling multiple ones if necessary.

The inductor used for a 52KhZ switching regulator is much much bigger…

…than it’s counterpart on the 210KhZ design.

At first glance, opting for MLCC is a miracle. Let us compare the GRM21BR61A106KE19L to an electrolytic capacitor from a well known brand – by going through hole or by switching to a lesser brand, the electrolytic capacitor would of course become a bit cheaper…


Taking a look at the actual specifications of the capacitor reveals the situation to be less rosy. The figure, taken directly from Murata’s datasheet, shows that the capacitance of the component decreases significantly as the applied voltage raises.

Actually getting this information can be tricky; whilst first-rate vendors usually provide this data themselves, designers working with cheaper parts can often find themselves forced having all oscilloscope and using the good old RC discharge curve to find out more.

As if this was not enough…

Recent news stories also point to shortages in the MLCC capacitor supply chain. Most distributors now provide warnings about manufacturing delays, with some parts having lead times of up to 38 weeks.

Whilst this might not be a problem for a large vendor such as Apple or Samsung, a smaller company with small order volumes will likely find itself on the short end of the stick if push comes to shove.

In short, MLCC capacitors do provide benefits, but are not a silver bullet for all capacitor-related problems. Tune in soon for the second part of our story, which looks at the various ways designers can handle the stock shortages in the MLCC capacitor market using OEMsecrets tools and a bit of ingenuity.