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 […]
Two-terminal diodes are among the best-known components in electrical engineering: electronics 101 cannot be passed without them – BAV99 and BAS16. Combining multiple diodes reduces part count and assembly cost.
Candidate number one is the BAS16: a classic diode with 100V of reverse voltage capability and a decently fast switching time of about 4nS. It I s interesting mainly due to the VV and VY families, whose configuration is shown in the image:
With the BAS16, it takes three to tango (Source: NEXPERIA)…
This arrangement makes the parts ideally suited to attenuators: if a series of similar elements must be protected from reverse voltages, a BAS16VV reduces the number of components the pick and place machine must touch.
Sadly, the BAS16 family is extremely wide: in addition to the three diode parts, single diodes can also be had (albeit in the larger SOT23 form factor). Keep an eye when ordering, as mess-ups lead to production delays.
Tango to Two…
Classic four diode bridges usually come as four diodes or a dedicated rectifier pack. Vishay’s BAV99 combines two diodes in series and provides an additional middle tap output as shown in figure two.
…the middle tap makes good use of SOT23 housing’s three pins
Obviously, two BAV99s make for a great rectifier – a job hampered by their relatively low reverse voltage resistance which is in the area of 70V. Another interesting application involves separating “areas of concern” – if a process computer pulls an attenuator down, adding a diode chain provides a small additional buffer for other recipients.
Nexperia’s version of the BAV99 is even more advanced – as shown in figure three, they even offer a housing with two of these diode assemblies combined.
The BAV99S contains four diodes…
Should we tango?
From an economic point of view, simplifying boards almost always makes sense. When deciding for and against these diodes, do not limit yourself to price and space factor-based models. While the two parts mentioned in this story are quite available and have been on the market for some time, always keep in mind the incre