When you need to buffer the output of an R-2R ladder or an RC filtered PWM signal, an op-amp is a single chip option. Unlike a discrete NPN transistor like a 2n3904, there is a lot going on inside of an LM741—or any op amp for that matter.
What if you could look inside of the op-amp? Wouldn’t it be cool to see how many transistors make up these small chips?
At the core, this is a soldering kit. You get an oversized PCB, all of the necessary parts, and a few mechanical pieces. For the record, I also built up the Three-Fives. That is a giant 555 chip it.
Every electronics geek owes it to themselves to have one of these on their bench. Not only are the designs functional, but they also look so cool.
Clean silk-screen identify each section of EMSL’s XL741 op-amp, which I like. So if you wanted to understand how operational amplifiers work, you could easily start poking around and see how different sub-circuits operate.
For my testing, I decided to build a simple voltage-follower. My intention was to buffer the output of an Arduino Pin, with the future intention of buffering the output of an RC-Filter.
Then I was suddenly hit with why there is one LM741 in my electronics kit and a bunch of LM358’s.
Notice something? Yeah, it doesn’t go all the way down to zero volts. So why is this 741 not going from 0 to VCC? Well, Here’s a scope capture of a real LM741.
Yup. That’s right, now I remember. LM741s suck as single-supply op-amps. For reference here is an LM358.
Regardless, the XL741 is performing much like the LM741.
Is the EMSL’s XL741 Worth it?
Discrete components crammed on a circuit board are no match for a single piece of silicon, in terms of performance. The kit is easy to build with clear instructions, labeled components, and a very highly quality printed circuit board (PCB).
The finished build is nothing short of gorgeous.
No question asked: 5 out of 5 LEDs.
Let’s Build the XL741
For Episode 16 of AddOhms, I remixed a Periscope live build of my XL741. Here’s what it looks like to build one: