I’m behind schedule, so this week we will have 3 chips (from the same family). Instead of reviewing some fancy shmancy ASIC, we’re going to get back to basics with a nice, cheap opamp set.
Cause sometimes you just want an opamp. Nothin’ crazy, just want to add some voltages, maybe amplify something a bit. Possibly do some filtering, or interface to a sensor, or some audio stuff.
Well, my friend, the TL08x’s are your bread & butter.
4 MHz gain bandwidth (internally compensated)
Not rail-to-rail so 8V rail is minimal, a split +-15 is great but even +- 5 is good to go
Input offset voltage is
Input bias current
JFET input stage so you’ve got a ridiculous 10^12 (1 Mega-Mega ohm!) input resistance
13V/us slew rate
noise figure: 25nVrtHz
Lets compare it to the ye olde favorite, the LM741:
1 MHz bandwidth
Input offset voltage:
Input bias current:
Transistor input stage, >300Kohm input resistance
0.5V/us slew rate
noise figure: 30 nVrtHz
So the worst case offset voltage is better on the ‘741, but the gainbandwidth, the input resistance, input bias current and the slew rate sucks in comparison to the ‘081. And the 081 is a little less noisy too.
The dual in 8DIP is a mere $0.64 from digikey, mouser has them from STMicro for $0.37. Thats cheaper than a cup of coffee!
So, when you want to have a stash of opamps for prototyping, these are your best bet. I especially like just having the duals and quads around, and then swapping out a better specified opamp later on in the project if it’s called for.
The offset voltage usually isn’t so horrid, of course, although I still suggets coupling AC if you’re cascading gain stages. Congratulations, TL082, you are the Chip of the Week!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, or even use Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for MakeCode, CircuitPython, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Python for Microcontrollers — Python snakes its way on the SparkFun SAMD21 Mini, Hackaday.io, 10k thanks, and Tim’s magazine #Python #Adafruit #CircuitPython @circuitpython @micropython @ThePSF @Adafruit
Get the only spam-free daily newsletter about wearables, running a "maker business", electronic tips and more! Subscribe at AdafruitDaily.com !