Greetings,
I am currently a first semester junior and would like a little more understanding for a lab I am working on. We're currently learning about Schmitt Triggers and building them in lab to see their effects on switch bouncing. But at the end, we had to build a unity-gain inverting amplifier. No big deal; built it fairly quickly but was surprised at the end result. Here's the schematic:
We were required to input a 100 mV sine wave at specific frequencies and measure the output (5 kHz, 50 kHz, 500 kHz, and 5MHz), verifying that the gain was, in fact, constant. And for the most part it was. Once I started venturing into the ~500 kHz range, the output began to drift more and more out of phase. By the time I had gotten to 5 MHz, it had driven to zero. Even stranger, we also supplied an 8V / 30 us (~33 kHz) sine wave and it output a sawtooth wave! The following thumbnails are my outputs at 5 kHz, 50 kHz, 500 kHz, 5MHz, and 8V / 33 kHz, respectively.
Obviously this behavior is a desired outcome of the lab but I am having difficulty finding material to understand this behavior. I feel like I want to understand unity gain amplifiers at high frequencies, but the last waveform seems to contradict that considering it was only 33 kHz. I did notice the drastic chance in the supplied amplitude between the 100 mV and the 8V. As usual, I am certainly not asking for direct answers; I love reaching the ah-ha moments with as little help as possible. However, is there a general direction someone could point me in as far as reading material or theory?
I am currently a first semester junior and would like a little more understanding for a lab I am working on. We're currently learning about Schmitt Triggers and building them in lab to see their effects on switch bouncing. But at the end, we had to build a unity-gain inverting amplifier. No big deal; built it fairly quickly but was surprised at the end result. Here's the schematic:
We were required to input a 100 mV sine wave at specific frequencies and measure the output (5 kHz, 50 kHz, 500 kHz, and 5MHz), verifying that the gain was, in fact, constant. And for the most part it was. Once I started venturing into the ~500 kHz range, the output began to drift more and more out of phase. By the time I had gotten to 5 MHz, it had driven to zero. Even stranger, we also supplied an 8V / 30 us (~33 kHz) sine wave and it output a sawtooth wave! The following thumbnails are my outputs at 5 kHz, 50 kHz, 500 kHz, 5MHz, and 8V / 33 kHz, respectively.
Obviously this behavior is a desired outcome of the lab but I am having difficulty finding material to understand this behavior. I feel like I want to understand unity gain amplifiers at high frequencies, but the last waveform seems to contradict that considering it was only 33 kHz. I did notice the drastic chance in the supplied amplitude between the 100 mV and the 8V. As usual, I am certainly not asking for direct answers; I love reaching the ah-ha moments with as little help as possible. However, is there a general direction someone could point me in as far as reading material or theory?
