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 […]
SMD resistors are seen as a component which “just exists”. Designers are usually not willing to give the part more attention – unless one fails or becomes unaccurate due to overheating or environmental problems.
Vishay’s TNPW family, represented here by family member TNPW120614K3BEEA, is an excellent candidate for all situations where high amounts of reliability are needed in a SMD package. The resistors most outstanding feature is its incredible insensitivity to moisture and heating. The datasheet claims that the parts keep their value even at 85°C and when confronted with a humidity of 85%.
Vishay prides itself on offering a wide variety of value and heat dissipation options, most of which are outlined in the table.
The TNPW family is available in various case sizes…
Let the OEMsecrets team share an old hint here: designing resistor values very close to the maximum allowed amount of power dissipation is a real anti-pattern. Especially when working in automotive or motor control scenarios, spikes will crop up – in many cases, using a resistor with a sufficiently large power dissipation capability is enough to neutralize them.
Finally, developers planning to use the parts in their project are well advised to contact their distributor. Vishay is willing to send lots consisting of parts in a single date code, which – in theory – should reduce the spread of the individual parts even further.
However, it is not sure whether this is even needed. Vishay claims that every single part is optimized using a laser trimming process known from traditional precision resistors. Furthermore, parts are tested on the one by one basis, which means that that promised accuracy should be met without issues.