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Topic: MicroSD drawing too much current? (Read 300 times) previous topic - next topic

ddesousa

Nov 23, 2017, 12:51 am Last Edit: Nov 25, 2017, 12:37 am by ddesousa
Hi there,

I am using the microSD module by adafruit and am encountering some issues.

First of all, I noticed that the module can draw up to 100 mA of current at a point. In my application this module is tied to the same 3V3 rail as other sensors, a display and a Bluetooth module.

When using this module, it looks like my data coming from the Bluetooth HC-06 module becomes corrupted and I am unable to interpret any data.

Both modules work independently. Is there anyway to fix this?

A subpar picture of the hardware:  https://drive.google.com/file/d/1bgggXI ... sp=sharing

Daniel


PaulS

Quote
Is there anyway to fix this?
What is the problem? The card NEEDS up to 100mA (or sometimes more) of current. You MUST provide a power supply capable of supply that much current. The onboard 3.3V regulator is NOT.
The art of getting good answers lies in asking good questions.

Wawa

#2
Nov 23, 2017, 01:21 am Last Edit: Nov 23, 2017, 01:21 am by Wawa
First of all, I noticed that the module can draw up to 100 mA of current at a point.

In my application this module is tied to the same 3V3 rail as other sensors, a display and a Bluetooth module.

A subpar picture of the hardware
The module runs on fumes (74HC4050), but the CARD could use up to 150mA.

Why don't you use the module's onboard 3.3volt voltage regulator.

Which Arduino do you use, and where is your code.
Link does not work.
Leo..

ddesousa

A copy of my code: https://drive.google.com/file/d/1z2jQqirSWXDxySJKcdbpqYY_Mt41-2t7/view?usp=sharing

Photo of my hardware: https://drive.google.com/file/d/1bgggXIS9Jj7m-M9eRnkdNELz6hzqKNJ-/view?usp=sharing

I am using a:
SAM D21 mini breakout (sparkfun)
0.96 " OLED Display (adafruit)
MAX30102 Heart Rate Sensor (Maxim Integrated)
HC-06 Bluetooth
MPU6050 Acceleromter (DFRobot)

I brought up this problem as I have noticed that my Bluetooth module cuts off some information when I recieve it and this has been happening ever since I implemented the SD Reader.

Something like a time will go from 11:20;23 PM to 1:20:23 PM.

Thanks

Wawa

I think I see badly soldered pins on the micro board, and some pins not soldered at all.

Don't know these micro boards, but the schematic diagram shows that "V-in" (pin1) is USB supply through a backflow protection p-channel mosfet. This (naming) is different from regular Arduinos.

The HC-06 modules I know must be powered from 5volt, because they have their own 3.3volt regulator.
I think I see that you power the HC-06 from the V-in pin.
But why power the SD from the 3.3volt pin of the micro (with a tiny onboard 3.3volt regulator), when the SD card has it's own regulator. Just power the SD card (5volt pin) also to the V-in pin of the micro.
Don't know which MPU6050 you have (post links).
Leo..

ddesousa

Hi Wawa,

Thanks for your questions.

Quote
I think I see badly soldered pins on the micro board, and some pins not soldered at all.
I can confirm all the pins are soldered properly. The devices work just not together.

Quote
Don't know these micro boards, but the schematic diagram shows that "V-in" (pin1) is USB supply through a backflow protection p-channel mosfet. This (naming) is different from regular Arduinos.
The HC-06 module is being powered by VIN as it disrupts the rest of the module when connected to 3v3. The modules data sheet says it is rated for supply anywhere between 3.6 and 6 V

Quote
But why power the SD from the 3.3volt pin of the micro (with a tiny onboard 3.3volt regulator), when the SD card has it's own regulator. Just power the SD card (5volt pin) also to the V-in pin of the micro.
This is a 3V3 based application. In the end, I will be using a 3.7 V battery to power the mcu and regulate the 3v3 voltage using the on board regulator.

Quote
Don't know which MPU6050 you have (post links).
SAM D21 mini breakout https://www.sparkfun.com/products/13664
0.96 " OLED Display
MAX30102 Heart Rate Sensor https://www.maximintegrated.com/en/design/reference-design-center/system-board/6300.html
HC-06 Bluetooth
MPU6050 Acceleromter  https://www.dfrobot.com/wiki/index.php/6_DOF_Sensor-MPU6050_(SKU:SEN0142)

Note: When I remove the heart rate algorithm, everything seems to work fine. Could the algorithm be taking up too much processing time?

Dan

TomGeorge

#6
Nov 24, 2017, 03:30 am Last Edit: Nov 24, 2017, 03:35 am by TomGeorge
Hi,

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.

Some platforms and members, do not like going off forum to get code or images.

Thanks.. Tom... :)
Everything runs on smoke, let the smoke out, it stops running....

wvmarle

The HC-06 module is being powered by VIN as it disrupts the rest of the module when connected to 3v3. The modules data sheet says it is rated for supply anywhere between 3.6 and 6 V

This is a 3V3 based application. In the end, I will be using a 3.7 V battery to power the mcu and regulate the 3v3 voltage using the on board regulator.
I see two problems here.
First: the voltage of your battery will most of the time be lower than 3.7V so you're really at or under the specified limit for the HC06 module. You better find a Bluetooth module that's designed for 3.3V.

Second: I doubt the regulator on your board has that low a minimum drop-out. I think there are some regulators that indeed do 0.4V but most are above that, and anyway the moment your voltage drops below 3.7V even that 0.4V drop-out gets you below 3.3V.
Quality of answers is related to the quality of questions. Good questions will get good answers. Useless answers are a sign of a poor question.

TomGeorge

Hi,
To quote the adafruit site;

https://www.adafruit.com/product/254

Quote
  • Onboard 5v->3v regulator provides 150mA for power-hungry cards

Tom... :)
Everything runs on smoke, let the smoke out, it stops running....

ddesousa

Quote
First: the voltage of your battery will most of the time be lower than 3.7V so you're really at or under the specified limit for the HC06 module. You better find a Bluetooth module that's designed for 3.3V.
Okay I agree but I am currently powering the Bluetooth module with USB power anyways which is currently about 4.3 V

Quote
Some platforms and members, do not like going off forum to get code or images.
Sorry Tom but my code was too long and I wanted to provide the people in the forum with the full code.

Quote
To quote the adafruit site;
Good point. I have noticed that the SD might not be the problem. When I do not use my new heart rate module (MAXREFDES117), everything seems to work and the time and date display properly. Now , theres a complex peak detection algorithm going on in the background. Could this be disrupting the UART interface between the mcu and BT
Library: https://github.com/sparkfun/SparkFun_MAX3010x_Sensor_Library

TomGeorge

#10
Nov 24, 2017, 04:18 pm Last Edit: Nov 24, 2017, 04:26 pm by TomGeorge
Hi,
If your code won't post to tags, attach it to the post.

How are you powering your project at the moment? Off the PC USB?

If so then what ever you have connected to Vin on the nano will not be receiving proper regulated supply.

HC-06 should be connected to 5V, as you have said it will work on 5V.

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

Tom... :)
Everything runs on smoke, let the smoke out, it stops running....

ddesousa

H Tom,

Thanks for the reply. I have attached the code to OPa.

I am powering off of USB but I have tried off a constant power supply and I obtain the same results.

Again, I do not think this is a hardware issue as both systems work independently.

I believe the HR algorithm I currently have is taking too much processing or something related to my code. Please take a look.

Thanks,

DD

TomGeorge

Hi,

Quote
constant power supply and I obtain the same results.
How is the constant power supply connected, via USB or Vin and gnd?

Tom... :)

Everything runs on smoke, let the smoke out, it stops running....

ddesousa

Hi Tom,

I used a power supply found in my lab, powering the entire module at 5 V.

DD

TomGeorge

Hi,
Through the 5V pin or through the Vin?
It should  be 5V pin..

Thanks.. Tom.. :)
Everything runs on smoke, let the smoke out, it stops running....

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