1. ponas.jonas

    Force Sensitive Resistor Design Question

    Hi everyone, I wanted to post in this forum to ask a question regarding a PCB I have designed. I have just received my PCB and am trying to program it, but I am not getting any values, so I immediately thought that something is wrong with my electronics... I am using a force sensitive resistor...
  2. M

    Question on how to improve my analog audio amplifier circuit

    Hello everyone! My original intention was to sample analog audio via the analog pin of the Arduino Uno Microcontroller. For testing purposes I used my phone as the audio source and plugged in a 3.5mm AUX cable I extracted from some old phone headphones. Then I used the R speaker audio wire to...
  3. Dominator008

    Creative Inspire T3030 Subwoofer No Sound

    Hi, I have a Creative Inspire T3030 2.1 speaker system of which the subwoofer isn't working. The two satellite speakers and volume control are working, as well as the headphone jack. Very unfortunately there is no schematic for this particular product online. The only references are schematics...
  4. N

    Resistors connected to op-amps

    Hello everyone! I'm trying to solve this assignment and I'm not sure what to do with all those resistors. Should I calculate an equivalent resistance for each group? And how do the resistors connected between the terminals of the op-amps influence the circuit?
  5. T

    Schmitt Trigger vs RC Low pass Filter for signal conditioning

    If I have an application where I don't need to sample a sensor fast at all, and I include an analog LPF, such as an RC filter, does a Schmitt Trigger serve any purpose? Conversely, could I use a Schmitt Trigger instead of the RC LPF and achieve the same results?
  6. U

    How to use transistor as a variable Regulator?

    I'm designing a variable power source from 5V to 30V with 600mA. Input voltage is VIN = 36V. I tried the below circuit. VREF is given from microcontroller DAC. I tried using N-MOSFET, P-MOSFET, NPN, PNP (with modifications). I set a the output voltage as 20V. This circuit works fine with no...
  7. L

    Square-Triangle generator project - variable frequency

    I'm working on a project for school where we must generate a square and triangle wave from fixed supplies in a lab using only RC components as well as a specific list of active components: We are also NOT allowed to use variable capacitors or ganged potentiometers. The circuit must have...
  8. Tiago Rocha

    LM741 Op Amp not working

    So, i want to use an Op Amp with inverting topology to invert -3,3v into 3.3v (gain of -1). when i simulated it as in the figure i've used single power supplies and it worked (even with 5v in simulation). But in the practice i've tried 5v,12v and 15v single power supplies and none of them made...
  9. MrsssSu

    Maintain constant voltage across a variable load (op-amp)

    Hi readers :), Vin is fed with the PWM signal coming from an op-amp to be amplified and fed into the load R1 (1 Ohms). The purpose I design this is I want the voltage source to be a constant 5V which is independent of the load (1 Ohms or 100 Ohms). So basically, this circuit has an op-amp which...
  10. R

    Simple non inverting op-amp circuit to amplify mic sound don't work

    Hi all Considering this simple circuit When I connect it as shown the sound became amplified for 2 seconds then it stops. So I have to connect the jack to pin 3 instead of pin 1 .. how to fix this Thanks a lot.
  11. C

    TL072 op-amp voltage follower acts weird

    Hi All, I hope that I am posting to the right forum. After days of searching, reading, experimenting, I still have not been able to find a proper solution which I can tailor to my issue, so it is time to ask you guys. I made a voltmeter which consists of an Arduino microcontroller and an...
  12. Alex_Khan

    Demodulator design for differentially modulated signal.

    Hello, I am demodulating differential signal using LPF based demodulator. The schematics of the entire system is attached which include diff modulator, coupling capacitors, and demodulator. A modulated signal of 17 Mhz is demodulated. For the demodulator, I designed a 2-stage differential...
  13. R

    Oscillations on output of loaded LM675 for all positive voltages.

    Hello, I'm trying to use an LM675 power op-amp IC as an output buffer for a signal generator. For stability, I've configured this IC as a non-inverting amplifier with a gain of 11 as per the circuit diagram below. As also recommended in the datasheet, I routed separate ground returns for the...
  14. P

    OPA657 Op-Amp oscillating for unknown reasons

    Greetings, I am working on a Lidar system for a senior project and am running into issues I am unable to solve with my circuit. The project requires the use of an amplification and comparator circuit in order to take the detector output up to a level that will trigger a TDC controlled by a...
  15. S

    Op-Amp buffer Enable/Disable

    I am designing an electric veichle controller for a University project. The motor driver receives an analog signal (0-12V) to adjust the speed. I use a digipot followed by a buffer to convert the digital signal of the controller to ana analog one. Now I need some way to enable an disable each...
  16. Mohsin Anees

    Debugging Constant-Current source

    What I'm trying to do? I'm making a constant-current source based off an existing design. The specs of the existing design are: Existing Design The design is of a constant current source capable of outputting 4-20mA output current from an input voltage of 0-2V. The Problem The problem is...
  17. stn_93

    Need Help Comrades! - Dark sensitive led flasher circuit

    Hi Guys, hope all's well. I was designing a dark-sensitive LED blinking circuit for myself and need some help. Following is all about my little project. Scenario I want to switch on my LED bank automatically in the dark. There are 150 LEDS in my LED bank. The attachment includes my design...
  18. A

    Using a unipolar DAC as a bipolar DAC

    Hello, I'm currently working on a project that requires the use of an MCP475 DAC. Currently, it is being powered from the 3.3V source from on a Raspberry Pi and hence works in the range of 0V to 3.3V. I need it to work in the range of -3.3V to +3.3V. By reading the spec sheets I found that I...