Tell me more ×
Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It's 100% free, no registration required.
up vote -1 down vote favorite

I'm tasked with getting analog data off various instruments (no more than ten analog signals) on a weather station.

I need help choosing a single chip (preferably SOIC or DIP) that can do this. I don't need particularly high frequency nor high bit resolution.

Can anyone more experienced than me suggest something?

Many thanks in advance,

share|improve this question
Can you define a bit better what is "high frequency" and "high bit resolution"? Maybe 100kS/s and 12 bit or 50 kS/s and 8 bit or something else? – AndrejaKo May 30 '12 at 18:14
1  
Can you clarify the serial stream you're looking to get out of this chip? What's the intended destination? What's the signal path? Wireless, wired, serial, ethernet? Is any of that defined? If you don't care where it ends up, a single microcontroller with an integrated A/D may be your best bet. If you need to send the data over some distance, and don't have a defined protocol for doing so, we can make suggestions for that as well. – Remiel May 30 '12 at 18:26
10 bits should be fine. Ten samples per second should be fine. – Eamorr May 30 '12 at 18:32
This weather station will be kept outdoors. Therefore, it needs to be battery/solar powered... However, there is a building right beside where the station is going, so I'm thinking of Zigbee'ing the data to the building and GSM'ing the Zigbee data on to my web server. – Eamorr May 30 '12 at 18:33

closed as not a real question by Olin Lathrop, Kevin Vermeer May 30 '12 at 21:11

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, see the FAQ.

1 Answer

up vote 1 down vote accepted

My best suggestion would be to put a microcontroller on your sensor board, and then send the data via serial to a dedicated wireless node of whatever form you settle on. I'd start with the Microchip part selector: https://www.microchip.com/maps/microcontroller.aspx

If the app is a weather monitoring station, you'll probably want a chip with an extended temp range. Since you specify SOIC or DIP, I'd guess you're soldering by hand, and that DIP is preferable. All that, plus ten twelve-bit A/D channels, limits you to a few dozen active parts. Out of those, I've personally used the dsPIC 30F4013 in a number of applications. It supports SPI, CAN, UART, I2C, and has many spare pins that could be used for a parallel interface.

If you use this chip, I suggest that when configuring the A/D converter, you use the Vref+ and Vref- pins as your references, instead of the AVdd and AVss pins. It eats two of the thirteen available A/D pins, but the AVdd and AVss pins have an ~50 mV result floor. Below that, you don't get anything out of the converter.

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.