Hello Guys,
I am supplying the voltage 3.3 to the ADC from raspberry pi.
Gain = 1 mean (4.09V)
My question is
is it possible for me to measure the signal greater than 3.3V upto 4.09V on any channel????
I have read, its not possible to measure the signal greater than the supplied voltage to the ADC, which is in my case 3.3V
ADS1115 16 bit ADC
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- adafruit_support_bill
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Re: ADS1115 16 bit ADC
No. It is not possible to measure signals greater than VDD. And any voltage higher the VDD + 0.3V is likely to cause permanent damage to the device.is it possible for me to measure the signal greater than 3.3V upto 4.09V on any channel????
(See section 7. Absolute Maximum Ratings)
https://www.ti.com/lit/ds/symlink/ads11 ... e.com%252F
- sj_remington
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Re: ADS1115 16 bit ADC
You can use a voltage divider to reduce an input voltage to the allowable range.
- AsifSaeed
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Re: ADS1115 16 bit ADC
If i apply 5V to the ADC, then i can measure the signal on any channel upto 5V. right????adafruit_support_bill wrote:No. It is not possible to measure signals greater than VDD. And any voltage higher the VDD + 0.3V is likely to cause permanent damage to the device.
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: ADS1115 16 bit ADC
Yes. However now the i2c signals will be pulled up to 5v also, so you will need an i2c level-shifter to protect the signal pins on your Pi. https://www.adafruit.com/product/757
The voltage divider solution suggested by sj_remington is a bit simpler.
The voltage divider solution suggested by sj_remington is a bit simpler.
- AsifSaeed
- Posts: 10
- Joined: Wed Mar 24, 2021 6:48 am
Re: ADS1115 16 bit ADC
adafruit_support_bill wrote:Yes. However now the i2c signals will be pulled up to 5v also, so you will need an i2c level-shifter to protect the signal pins on your Pi. https://www.adafruit.com/product/757
The voltage divider solution suggested by sj_remington is a bit simpler.
great . Thank you for suport
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Talk about Adafruit Raspberry Pi® accessories! Please do not ask for Linux support, this is for Adafruit products only! For Raspberry Pi help please visit: http://www.raspberrypi.org/phpBB3/
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