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  1. 2

    Inverting input greater than non-inverting input = positive voltage?

    Hello, With the rails at +/- voltages, I was always under the assumption that when the voltage value at the inverting input is greater that the voltage value of the non-inverting input of an opamp, the output would be a negative voltage! OR With the rails, Vcc to positive voltage and...
  2. 2

    AC/DC Power supply with no neutral ???

    Hello, I am working on a home automation device where I need low powered electronics within the electrical box of a household switch. Typically we have the line and the neutral wires available in the box. Therefore a small AC/DC power supply would use the existing 120VAC line as the input to a...
  3. 2

    MRF24WB0MA schematic ?

    Is it possible to find the schematics for such a part: MRF24WB0MA Or is there a replacement circuit that does the same thing? 24V
  4. 2

    MOSFET question?

    Hello, In attachment below, the amp meter reads 4.78ma. I always figured that when R2 would drop to 20 ohms, the current would increase. But it simply stays the same!!! Why?? Wouldn't lowering the resistance allow more current through the circuit?? In other words, the current is...
  5. 2

    high IR led power?

    Hello, I would have a quick question about the TSAL6100 IR LED: http://www.vishay.com/docs/81009/tsal6100.pdf In the absolute maximum ratings section of the data sheet, it says that this led's forwards current is 100ma. But then it also says that the peak forwards current is 200ma...
  6. 2

    Tsop fails on extreme lighting intensities!

    Hello, I am using the Tsop4838 ir sensor and I am able to sense objects at different distances. I then tried to detect those same objects but with a flash light directed right on the tsop sensor. To my dismay, the sensor completely died off producing NO signal at all!!!! Is this...
  7. 2

    max44000

    hello, I have achieved a proximity sensor circuit with the tsop4838 ir sensor. I just ran into this part: http://catalog.gaw.ru/project/download.php?id=39995 Now, I would like to know if anyone used the max44000 part for proximity sensing ???? And can anyone tell me what is the maximum...
  8. 2

    Has anyone heard of Mikroelektronika?

    hi, has anyone ever used mikroelektronika products such as their compilers and so forth ??
  9. 2

    Can this be done using a JFET?

    Hello, Please view attachment OPAMP1. Here is a circuit that works exactly as I need it. This circuit was kindly provided to me by some fellows from this site. The last piece of the puzzle is I need to control R5 from my MCU. I would like to know if R5 can be replaced with a JFET as shown in...
  10. 2

    BJT Ramp?

    Hello, I am pretty new to trasnsistors and lately I had calculated a ramping circuit using a simple Pn2222 transistor. When the input was 2.0VDC at the base, Vc was 1VoltDC. As the input to the base voltage ramped up towards 3.3 VDC, Vc ramped down to 0.5VDC. Therefore, this circuit had a gain...
  11. 2

    TLC7226 data sheet?

    Hello, A problem I have is interpreting what the spec sheet is really saying... please consider the following!!!! Referring to the TLC7226 part and its spec sheet at: http://www.ti.com/lit/ds/symlink/tlc7226.pdf If you go to p.4 of the data sheet and look for: ri(ref) Reference input...
  12. 2

    Emitter bias feedback with REE?

    Hello, I have been experimenting with emitter bias feedback method for biasing a transistor. Please locate in the following link: When I did the circuit and calculated it with the typical values as shown in attachment T2-EBF-A.png (left side), the Ie calculated value was 0.101 ma but when...
  13. 2

    Kernel or Off the shelf OS?

    Hello, I am facing a crutial decision. If you are an experienced programmer or a project manager for a big IT/Electronics firm, your feedback would be very appreciated. Let's say your firm is developping a product with a *similar potential* of sales as the Iphone. However, the product I am...
  14. 2

    Power factor

    -------------------------------------------------------------------------------- Hello forum, I have been reading some lectures in this site and I have a question about obtaining the apparent power, true power, reactive power and the power factor of an actual AC circuit. Basically I am...
  15. 2

    General question about storing graphics!

    Hello, I have a quick question about storing graphics in external flash memory. I have my own GL which is able to retrieve text, icons or pictures from an 8MEG flash and displays them on either a 1.5 " or 2.0" color LCD. Here's the thing though, when I am using the 1.5" LCD and I display a...
  16. 2

    Looking for a 1.5" color LCD!

    Hello, Does anyone know where I can find a 1.5" color LCD (approximate resolution 176 x 132) with built in controller with MCU interface capabilities. I will interface this LCD with a PIC 32. I had found one from Optrex, but they told me that it is obselete. Any other suggestions is...
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