My Arduino Uno has Problem when works with ULN2003a Module and 7-segment Module

I make something for Optical Product with Arduino. But, My Arduino has a Problem when it works with ULN2003A and FND module.

ULN2003A is used to run relay, FND module is used to display the state of relay.

I use Arduino with 12V/1.5A DC Adapter and the relay consume 88mW

The Problem is My Arduino is reset when works with ULN2003A(includes relay) and FND module.

Curiously, it works normally when run separately.

I checked the awareness of the short circuit problem and confirmed that it was a power shortage problem.

but, those were not Problem.

One strange thing is that the regulator on Arduino is hot.

but, I know that 7~12V is recommended input voltage. so, I think it isn't problem.

Then, What should I check to solve this problem?

Hi,
Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html . Then look down to item #7 about how to post your code.
It will be formatted in a scrolling window that makes it easier to read.

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

You are drawing too much current through the 5V pin of the Arduino, this is causing the regulator to overheat and when you operate a relay, the 5V drops and resets the controller.

What model Arduino are you using?

Thanks.. Tom... :slight_smile:

"FND module" What is that? Is it the same as "7-segment module" ?

Please provide full details on all the hardware you mention, we need to know this.

Note that you only can draw <=100mA from (any pin of) an Uno when the Uno is powered with 12volt.
If the power for the FlexibleNumericDisplay and/or relay is coming from the 5volt pin, then that could be the problem.
The 5volt regulator on the Uno will overheat and shut down (or release the magic smoke).
Try powering the Uno with a 5volt cellphone charger, connected to the USB socket.
Leo..

MarkT:
"FND module" What is that? Is it the same as "7-segment module" ?

Please provide full details on all the hardware you mention, we need to know this.

Yes, "FND module" is 7-Segment Module.

Wawa:
Note that you only can draw <=100mA from (any pin of) an Uno when the Uno is powered with 12volt.
If the power for the FlexibleNumericDisplay and/or relay is coming from the 5volt pin, then that could be the problem.
The 5volt regulator on the Uno will overheat and shut down (or release the magic smoke).
Try powering the Uno with a 5volt cellphone charger, connected to the USB socket.
Leo..

How can I know that Arduino can be draw <=100mA when the Uno is powered with 12volt?

Is it calculated value? then, How can I calculate?

Please let me know. Please...

Hi,

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Thanks.. Tom... :slight_smile:

TomGeorge:
Hi,

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?

Thanks.. Tom... :slight_smile:

Here is My Circuit.

Thank you :slight_smile:

Hi,
Thanks for the schematic.
Ops diagram.


Are all the 5V devices using the 5V pin of the Arduino?

Are the relays using the 5V supply?
If so 88mW will need;
P = V * I
0.088 = 5 * I
I = 0.088 / 5
I = 0.0176 A
I = 17.6 mA. per relay.

What are the specs on the FND module, can you post link to data/spec or where you purchased it thanks?
Note that some of the I2C modules are 3.3V.

Tom.... :slight_smile:

TomGeorge:
Hi,
Thanks for the schematic.
Ops diagram.


Are all the 5V devices using the 5V pin of the Arduino?

Are the relays using the 5V supply?
If so 88mW will need;
P = V * I
0.088 = 5 * I
I = 0.088 / 5
I = 0.0176 A
I = 17.6 mA. per relay.

What are the specs on the FND module, can you post link to data/spec or where you purchased it thanks?
Note that some of the I2C modules are 3.3V.

Tom.... :slight_smile:

Yes, The Relay consumes power in Arduino. Arduino are supplied power with 12V/1.5A Adapter.

I'm using 7 segment below

*Shop
: http://mechasolution.com/shop/goods/goods_view.php?goodsno=249&category=052004008

*Datasheet

The product I bought will be the same as the one below.

As I know, 7 segment comsumes about 80mW.

And it operates on 2.4~6.0V and 6.9~14.1mA.

Hi,
What model Arduino are you using?
Can you post a picture of your project so we can see your component layout please?

Thanks.. Tom.. :slight_smile:

TomGeorge:
Hi,
What model Arduino are you using?
Can you post a picture of your project so we can see your component layout please?

Thanks.. Tom.. :slight_smile:

I'm using Arduino UNO.

I'll post block diagram of my project, instead of picture. Because, It's too messy.