Keysight 34470A and Texas Instruments DAC8734EVM - Review

Table of contents

RoadTest: Keysight 34470A and Texas Instruments DAC8734EVM

Author: peteroakes

Creation date:

Evaluation Type: Independent Products

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: Tektronix 7.5Digit DMM, other vendor DAC modules, already evaluating the actual DAC8734 device, just not hte EVM

What were the biggest problems encountered?: The DAC8723EVM Module relies on the evaluator having a means to connect a SPI enabled development board to control the DAC. One was not provided. In my case this was not an issue as I have plenty of Arduinos, Launchpads and Raspberry PIs among others to choose from but other road testers may not be so fortunate

Detailed Review:

This is the start of a multi post / video road test on the Keysight 34470A 7.5 Digit Truevolt DMM and the Texas Instruments DAC8734 Quad channel DAC Evaluation board

Keysight Link: - http://www.keysight.com/de/pd-2520154-pn-34470A/digital-multimeter-7-digit-performance-truevolt-dmm?cc=DE&lc=ger

Texas Instruments Link: - http://www.ti.com/tool/dac8734evm


Thank you Element 14, Keysight and Texas Instruments for selecting me for this road test, I am pretty excited to be doing this one

 

First up is the unveiling, and quick tour of the DMM, I will just perform a couple of quick tests on the DMM to see how easy it is to drive...

 

I will test the Ohms range using my Precision Vishay Bulk Film Resistance Standard, Remember this: -

This is the first time I have had a meter even remotely accurate and precise enough to check the standard, and the 34470A does not disappoint, here is a link to the Vishay Resistor Standard post: so you can see what it is - http://www.element14.com/community/groups/test-and-measurement/blog/2015/01/05/vishay-precision-resistor-standard--how-the-pros-made-one-for-me

 

I will test a couple of the volts ranges using a precision voltage standard designed by and sent to me by Ian Scott Johnston: - https://www.youtube.com/user/IanScottJohnston. Thanks Ian. Here is how he made it if you’re interested:-

https://www.youtube.com/watch?v=2Ssg05oFCbk

https://www.youtube.com/watch?v=z5Pnw9Xr2ME

Ian also has a bunch of other videos you may be interested in, so check them out while you’re there

 

OK, back to business, Unbox then a quick look at the Meter is all I will do in part 1.

 

 

I will review the DAC8734EVM module and other features of the DMM in the next few videos and posts including some more obscure features like measuring current and volts at the same time which the DMM technically cannot do but with a little remote programming and utilizing the Reference / Dual measurement capability it can be made to work. Also on the agenda is looking at the logging features and the digitizing and advanced triggering features.

I won’t bore you with looking at the basic range checks and verifying the accuracy of the meter as I have nothing better than this meter in the LAB so it would be more of a check of my other lab equipment. But I am sure you’re interested in seeing how it can be used for real world scenarios so if you have some ideas, add it to the comments

 

What is on the agenda is the following

The BAT Signal…., TBC If you’re curious see a previous post here: - http://www.element14.com/community/groups/test-and-measurement/blog/2014/05/10/33622a-arbitrary-waveform-generator-helps-batman-with-a-new-bat-signal

Characterize LIPO's and possibly other batteries using SCPI programming, Logging, the Keysight 33622A AWG and my Analog DC Load

Fast Signal capture using the Digitizer and advanced triggering

Measuring the Low power characteristics of a few micro-controllers and other devices like a Raspberry PI to trend power usage under various scenarios

I have already started reviewing the DAC8734 chip prior to the Road test on a breadboard using a Raspberry PI and windows 10, An Arduino UNO and a TI Launchpad… well a few actually, if you’re interested in that then you can also check out these posts. http://www.element14.com/community/community/designcenter/ti_launchpad/blog/2015/08/07/ti-launchpads-and-how-to-drive-the-dac8734-from-ti-aka-the-dac8734evm-road-test-board

http://www.element14.com/community/groups/arduino/blog/2015/07/28/arduino-and-how-to-drive-the-dac8734-from-ti-aka-the-dac8734evm-road-test-board

http://www.element14.com/community/groups/arduino/blog/2015/07/28/arduino-and-how-to-drive-the-dac8734-from-ti-aka-the-dac8734evm-road-test-board

More to come real soon

 

The DAC8734 Module is a great example of TI engineering and it has a lot of possible uses in my projects. My disappointment was that it did not come with a means to drive it. While this is not an issue to me, the other road testers may be left in the lurch without a suitable RPI, Arduino or Launchpad. Now there is a lack of sample code for the DAC8734 too so that was the reason I started playing with the chip way before the road test started and if you’re a reviewer or just someone wanting to play with the DAC8734, check out my other posts linked above, they all have the code provided and your welcome to use it.

 

Oh, if you’re wondering why the rating for the Demo categories are poor, well, there are rather lacking.

When it comes to BenchVue the 34470A DMM demos are all pretty standard (Lacks a WOW factor) but the demos that I have looked at on YouTube etc. so far are way out of date and in a lot of cases contrived scenarios and simply allude to what could be done, the programming ones have not been updated in many cases since 2005.


I am already working on several sample apps using windows 10, Visual Studio 2015 and a combination of USB, Ethernet and Serially connected devices (Battery testing scenario for example) that should demonstrate how easy it is to communicate with the 34470A and other instruments remotely and capture their data or control them. It really is not hard to remotly manage many instruments using almost any language that can talk to a com port, just vendors seem to make it look hard ?

Anonymous
  • I will have a look at the stability of the DAC over time, maybe even get the hot air gun on it too for checking temp stability.

     

    The 34470A is now the best (Accuracy and Precision) device in my lab so it will be the reference to check everything else

  • Hi Peter,

     

    Good start.

    The meter does look impressive.  Have you figured out how to verify its readings?

    Are you planning to look at long time stability of the readings?

    I am curious if the values change overtime due to the circuit or due to the meter.

     

    Thanks

    DAB

  • The two boards was a typo

     

    I mean the instrument and the board Sorry.

     

    Enrico

  • This road test has one evaluation board and one 34470A DMM so im not understanding the reference to two boards. This does not really lend itself to testing an oscilloscope ?, can you elaborate ?

  • Hello Peter!

     

    Very well done review. I like it and now I see that in my review (there was less things to show and speak about) one things I have nos spent too much time was about the first impact. Also a video is always a very good idea.

     

    Also interesting the idea to start a different road test for every part of the kit. In this specific case frankly I have understood that the two boards was something helpful to test the oscilloscope.

     

    Enrico