E absolute maximum ratings at 25°C free-air temperature (unless otherwise noted)†. Input-to-output peak voltage (8-ms half sine wave): 4N kV. standard single channel phototransistor couplers. These families include the 4N35, 4N36, 4N37, 4N38 couplers. Each optocoupler consists of. Cosmo 4n35 optoisolator for DC voltage measuring. Hi all, I’ve encountered a problem. I’ve tried to set the input current to the opto by using 5V.
|Published (Last):||25 September 2015|
|PDF File Size:||2.69 Mb|
|ePub File Size:||6.37 Mb|
|Price:||Free* [*Free Regsitration Required]|
Cosmo 4n35 optoisolator for DC voltage measuring. Cosmo 4n35 optoisolator for DC voltage measuring Hi all, I’ve encountered a problem. I’ve tried to set the input current to the opto by using 5V and ohm resistor, resulting less than 10mA input current. On the output side, I have put the voltage cosmmo 5V and resistor as 1k. It outputs fine, however, when I decrease the input voltage the output voltage increases.
Is the opto reverse biased? Cosmo 4n35 optoisolator for DC voltage measuring I can only guess at your circuit. I assume the phototransistor has a 1k collector load to 5V. So, when you reduce the input voltage the LED current will reduce so the collector cowmo will increase because the 43n5 drop in the 1k will reduce due to the reduced collector current. If that doesn’t make sense then maybe it will help to post your circuit, Keith. Cosmo 4n35 optoisolator for DC voltage measuring Hi Keith, here is my circuit, Post added at Cosmo 4n35 optoisolator for DC voltage measuring Cozmo, that is what I thought.
In which ccosmo my description which I guess didn’t make sense! If you reduce the input voltage the output voltage will increase. So you circuit 4m35 working correctly – although maybe not how you want it to. Cosmo 4n35 optoisolator for DC voltage measuring How do I improvised it to be directly proportional, Keith? I don’t mind if the output voltage is not same as the input, but if it’s proportional, I can mend the voltage reading by inserting a constant in the microcontroller.
Not only does it invert but the LED will be completely inoperative at low voltage and the linearity graph will look like a cross section of the Himalayas.
4N35 Optcoupler | 4N35 Datasheet
Cosmo 4n35 optoisolator for DC voltage measuring What you have will be inversely proportional which would be fine – it can be sorted out in software – except that if you were hoping to measure input voltage in that way you will fail because of the non-linear relationship between the LED current and voltage.
Cosmo 4n35 optoisolator for DC voltage measuring Hurm But it is quite expensive at 11usd per unit. I need to use 8 pieces lol. I guess there’s no substitute for the hcpl eh?
Is there any cheap optoisolator that you guys can recommend? Thanks Post added at Cosmo 4n35 optoisolator for DC voltage measuring You can convert the input voltage to frequency and then you can fosmo a opto for isolation. A simple timer can convert the voltage to frequency is a cheaper alternate.
Cosmo 4n35 optoisolator for DC voltage measuring I see. But I think it would be complicated as I would need 8 timer and 8 4n35 for my project. 4n3 think I will just let the ADC port get the signals directly from the contacts. It’s just a prototype. The reason I wanted to put optoisolators because the project will interface with a 11kV switchgear.
Stepped down to 5V of course! Cosmo 4n35 optoisolator for DC voltage measuring What voltage range are you trying to measure? Originally Posted by Iman Originally Posted by keithrs. Originally Posted by nandhu If you feel 4m35 timers and 4n35’s too much, you cismo use one timer and an opto and multiplex the input of timer. Another option is to use a micro which has 8 adc inputs measure it and send it thro the opto.
I am not sure it cpsmo be much simpler than using a to turn it into a pulse train though. A crude option if you just want a rough voltage measurement would be to correct the measured value.
In other words, plot the output voltage against input voltage and use the micro to correct for it. It will only work for input voltages high enough to turnt he LED on and it will be temperature sensitive though, so it is a very crude option. Cosmo 4n35 optoisolator for DC voltage measuring If you have a high voltage available to drive the LED then the accuracy will improve although you will dissipate more power in the LED drive resistor.
HOT IC 4N35 F4N35 4N 35 COSMO DIP6
It would be useful to know what you are trying to measure – where the source voltage comes from. If you have a high voltage available to drive the LED then the accuracy will improve although you will dissipate more power in cozmo LED drive resistor. Similar Threads use of a optoisolator in a power supply 4N35 fairchild 2.
Opto 4n35 for voltage sensing? Looking for a sensor for measuring V AC 9. Part and Inventory Search. AF modulator in Transmitter what is the Cosjo What is the function of TR1 in this circuit 3. Losses in inductor of a boost converter 9. Turn on power triac – proposed circuit analysis 0. Choosing IC with EN signal 2. Measuring cosjo gap of a magnetic core for home-wound inductors and flyback transformer 7.
Hierarchical block is unconnected 3. Digital multimeter appears to have measured voltages lower than expected. PV charger battery circuit 4. How reliable is it? Equating complex number interms of the other 6. CMOS Technology file 1. ModelSim – How to force a struct type written in SystemVerilog? Input port and input output port declaration in top module 2.
PNP transistor not working 2. Distorted Sine output from Transformer 8. How can the power consumption for computing be reduced for energy harvesting?
Dec 242: How do you get an MCU design to market quickly? Dec 248: Heat sinks, Part 2: Synthesized tuning, Part 2: The time now is