MicroCrystal RV-8803 – A Really Accurate RTC

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 that we are looking at a real time clock IC with an integrated crystal. This is beneficial in that the amount of space on the PCB is limited – the smallest component, after all, is one which does not need to be placed at all.

MicroCrystal provides an integrated crystal in its RTC IC

The housing of the chip is calibrated via a thermal sensor which permanently monitors the ambient temperature. MicroCrystal uses this technology to achieve impressive degrees of accuracy – in the range from -40 to 85 degrees celsius, a timing accuracy of but 3ppm is to be observed. As thje part does not, however, use a heater, it can make do with but 240nA of current.

Users of the Epson RX-8803SA/LC families will be happy to find out that the part shown in figure two is a second source – its register set is completely compatible with this once-famous Japanese real time clock. Furthermore, a clock output lets third-party ICs “parasite” away from the high accuracy signal generated inside the part.

While the pinout is simple, the housing is very small

Sadly, keep in mind that the housing of the part is extremely small and can not (really) be hand soldered. However, various developer and evaluation kits are available – they are available from various sources.

One interesting aspect of MicroCrystal involves the nomenclature – with them, a datasheet is but two pages long. The actual datasheet information goes by the name application manual, and can be found by visiting here.

Recent Articles
The Hitchhiker’s Guide to PCB Design
Want to create a solid, manufacturable PCB the first time? Get the only eBook you will ever need to upgrade your PCB knowledge and launch your... Read Article
Secure your supply with Future Electronics
Find what you need faster Hundreds of thousands of components. Three strategically-located Distribution Centers. ONE global IT infrastructure. Find what you need faster with access anywhere,... Read Article
Save 10% on Orders $500 or More
Promo code is valid for saving 10% on orders of $500 or more. Offer does not apply to products from Adafruit, DEEPWAVE DIGITAL, FTDI Chip, NVIDIA,... Read Article
Create Smaller, More Power-Efficient USB-C and USB-C Power Delivery Designs
Maxim Integrated’s extensive portfolio of ICs for USB-C and USB-C Power Delivery designs provide high levels of integration and flexibility that engineers need to create compact,... Read Article
Latest Solutions from CUI & Digi-Key
Read Article
Why Standard Products from ST are the right choice for your design projects!
Standard products matter! They are in virtually every design and you just need them right away with no fuss, no hurdles: just there.   Together with Farnell,... Read Article