Pages: [1]   Go Down
Author Topic: What is arduino Uno's ADC input Current Min and Max?  (Read 2103 times)
0 Members and 1 Guest are viewing this topic.
Offline Offline
Full Member
***
Karma: 0
Posts: 213
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

What is arduino Uno's ADC input Current Min and Max? Is the input min 40mA?
Logged

Newcastle, England
Offline Offline
Sr. Member
****
Karma: 3
Posts: 489
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

The inputs all have a very high resistance, so it will only draw a very small current. In order to draw more current, it must be at a higher voltage. Anything above 5V and it will be damaged.

Onions.
Logged

My website: http://www.harryrabbit.co.uk/electronics/home.html Up and running now! (Feel free to look round!) smiley-grin

Washington
Offline Offline
God Member
*****
Karma: 38
Posts: 790
Firefox & Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

They are high impedance input and will draw only uA.
Logged

Avoid throwing electronics out as you or someone else might need them for parts or use.
Solid state rectifiers are the only REAL rectifiers.
Resistors for LEDS!

South Texas
Offline Offline
Edison Member
*
Karma: 8
Posts: 1024
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

The ADC inputs are voltage sensing, and not current sensing. They are high impedance and will put little load on a circuit. The do not sink, they just sense. They do not draw any current, they sense voltage.

They have a MAX of 5V DC. If you need to sense a higher voltage you will need to make a voltage divider using a couple resistors in series.
Logged

Austin, TX
Offline Offline
Faraday Member
**
Karma: 71
Posts: 6141
Baldengineer
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

What is arduino Uno's ADC input Current Min and Max? Is the input min 40mA?

Min is about 0V and max is about whatever VCC is set to.

Analog in and probably tolerate 40mA.  However, since AnalogIn is a voltage measurement, the question of why such high current needs to be asked.
Logged

Capacitor Expert By Day, Enginerd by night.  ||  Personal Blog: www.baldengineer.com  || Electronics Tutorials for Beginners:  www.addohms.com

Washington
Offline Offline
God Member
*****
Karma: 38
Posts: 790
Firefox & Arduino rocks
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Also the analog pins can source/sink current if set as output in software.
Code:
pinMode(A1, OUTPUT);
In such case, their current capacity is the same as the other digital pins, 40ma absolute max <30ma recommended.

Logged

Avoid throwing electronics out as you or someone else might need them for parts or use.
Solid state rectifiers are the only REAL rectifiers.
Resistors for LEDS!

Manchester (England England)
Offline Offline
Brattain Member
*****
Karma: 604
Posts: 33432
Solder is electric glue
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
What is arduino Uno's ADC input Current Min and Max?
The minimum current is 0uA the maximum is 1uA as specified in the data sheet Section 28 under input leakage current.
Logged

Pages: [1]   Go Up
Jump to: