Dave Young of Young Circuit Designs is publishing a series of articles and videos on element14 every other week to describe his experience in upgrading from his trusty Tektronix TDS2024B to a new Tektronix MDO3104. See his other articles in the series:
(a) Tek MDO3104 Scope Upgrade Series #1: The 70% Test with a Tek MDO3000
(b) Tek MDO3104 Scope Upgrade Series #2: Digital Decoding and Triggering for Analog Analysis
(c) Tek MDO3104 Scope Upgrade Series #3: Trace Persist and Analog Triggering
(d) Tek MDO3104 Scope Upgrade Series #4: Computer Connectivity and Remote Control
Some people like to say that technical aptitude in the digital domain is a sufficient condition for understanding electronics based on the direction of the exciting technology that exists. As an analog engineer and educator, I can't say that I agree with that. However I do concede that at least a working knowledge of digital technique has become a necessary condition in working with electronics. Building the most beautiful analog circuit has much less relevancy if it can't connect with an iPhone. Sorry, Widlar.
I took this reality as a guide when looking beyond my 70% test for my review series of the Tek MDO3104 . Digital buses are a big part of my demo board life. I recently evaluated a temperature and pressure sensor that output directly to I2C. In order to see how accurate the sensor was, I needed some microcontroller code to get the data out.
Uh-oh.
This is exactly the type of situation that leads to 'Blame Badminton' between digital and analog engineers. One engineer presents data to knock the 'shuttlecock blame bomb' over the net to the other engineer's territory, which is similarly returned, continuing as a verbose volley until the real problem is found. What if the code is sending the wrong bits? What if the parasitic RC of the circuit is causing a questionable datastream?
In my video review below, I look at analyzing the system with both my Tek TDS2024B and the new Tek MDO3104. How does the mixed-domain performance do? Would I prefer to just have my old analog-domain scope instead of the fancy digital analysis offered by the MDO?
The results showed that the MDO absolutely killed it in this use case, which is good since I'm pretty sure Tek was considering this exact scenario when designing the MDO series. I was impressed with how well it could handle both analog and digital domains at the same time. The search function, which seemed like a total gimmick, turned out to be immensely helpful when trying to zero in on a collection of instances within one trigger event. The TDS on the other hand did a great job only of looking at the analog signal, and only as much as the memory depth allowed. I'm pretty good at setting up a solid trigger condition, but having gobs of memory depth is so much more elegant when trying to find one specific instance. I would have had to set up a logic analyzer with an external trigger to get the same information that the MDO offered in a few minutes and requiring no additional connections.
To sum it up, I wouldn't say I'm disappointed in my trusty TDS scope, but the extra functionality offered by the MDO certainly saved some time here. While a new MDO scope isn't cheap, this is one feature that makes spending the money and pulling the trigger now on a scope upgrade is worth it.
Dave Young of Young Circuit Designs is publishing a series of articles and videos on element14 every other week to describe his experience in upgrading from his trusty Tektronix TDS2024B to a new Tektronix MDO3104. See his other articles in the series:
(a) Tek MDO3104 Scope Upgrade Series #1: The 70% Test with a Tek MDO3000
(b) Tek MDO3104 Scope Upgrade Series #2: Digital Decoding and Triggering for Analog Analysis
(c) Tek MDO3104 Scope Upgrade Series #3: Trace Persist and Analog Triggering
(d) Tek MDO3104 Scope Upgrade Series #4: Computer Connectivity and Remote Control