Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

How to reduce voltage of 30mV to 10mV?(im a beginner)

Status
Not open for further replies.

garygothic

New Member
Hi there.Im a beginner in electronic stuff. May I know what are the options that I can do to reduce a very low voltage of 30mV to 10mV?Can I use resistor?or voltage regulator?If yes,what type of resistor/voltage regulator can I use?for your information,im doing a project on reading sensor output voltage.
 
Last edited:

Nigel Goodwin

Super Moderator
Most Helpful Member
Just two resistors, called an 'attenuator' or 'potential divider'.

Values depend on the source and load impedances, which is why your question is far too vague.
 

garygothic

New Member
Im using two sensors to run a sequential step motor: sensor1 and sensor2. Sensor1 produce Vout (voltage output) ≈ 30mV for every 1% increase meanwhile sensor2 produce Vout of =10mV for 1C increase. Im planning to lower the sensor1 voltage so that it will have almost the same Vout as sensor2. Your help is very much appreciated.
 

garygothic

New Member
Maximum humidity percentage is 100% and maximum temperature value is 125C.Im using pic16f917 microcontroller and Im using this demo board to run my motor. Im planning to run humidity sensor using the demo board (Replacing the light sensor) but the Vout for humidity sensor is different compared to light and temperature. So the only way I can run the humidity sensor is by lowering down the Vout .
 

garygothic

New Member
The value for humidity are not accurate when it is shown on the demo board.A value from 120 to 255 keeps popping out.It is suppose to be a value from 0 to 100 only.Unlike temperature and light,the demo board will shows both sensor's value that I wanted.
 

Gayan Soyza

Active Member
To show the humidity 1% you have to wait 30mV.But the problem is your hardware gives 10mV increments.To show humidity wait 3 times the 10mV increments.Or divide the AD reading by 30.

Ex:if AD reading 75mV then show = 2.5% (75/30)
 

garygothic

New Member
May I know how to divide using assembly language?My converted value would be taken from ADRESH and move to w (movf ADRESH,w) then I will show it on the LCD.
 

garygothic

New Member
No. I did not used division codes in my program. I just found out that the pic16f917 can read the analogue voltage from the humidity sensor.I can manually compute the humidity value using this formula: %RH = ((Vout/5)-0.16)/0.0062 But now I'm having problem with the Vout from the humidity. Since the Vout value are not steady,the output value from ADC displayed on the LCD keeps fluctuating up and down (random numbers from 0-255). By the way,I'm using this formula to compute the value that are displayed on the LCD = (Vout/5)*255. So now I'm planning to make the ADC to read one value at an interval times and convert it but do not know how to do this. Someone told me to use sample-and-hold,other told me to use RC circuit.I have a very little knowledge on these terms and usage. Anyone can help me on this?
 
Status
Not open for further replies.

EE World Online Articles

Loading
Top