MSP-EXP430G2 Launchpad

SIDDHARTH MOHAN

Hi all , i have MSP-EXP430G2 Launchpad, i want to increase temperature rise of a SMT resistor by varying the power through it, any suggestions on how can this be achieved using this launchpad?

is it possible to use a - resistor already present on this board?

over 9 years ago

0 Dennis Eichmann over 9 years ago

Guru 74080 points

To get a better understanding I would be interested in your application - is it only heating up a resistor or is there something behind it?

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks, i want to check the temperature rise for SMT resistors when the power through them is varied. I want to perform analysis on MSP430 launchpad because i think it has a ground plane. If not then kindly let me know

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

Well I do not really see the requirement for a microcontroller here. A power supply with current limiting function is all you need. Connect the (low value) resistor to the power supply and increase the current to increase the power dissipation in the resistor.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

the boundary conditions matter a lot to me while performing this experiment hence i need a proper board with a ground or power plane. So can you pleas suggest some means to use an onboard resistor for this? can PWM be used for varying the power?

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

The LaunchPad is not made for heating up resistors, so this might not be the right way. PWM can be used, yes. This is a job the MSP could do - driving an external MOSFET that switches the current for the resistor. But there is no resistor on the LaunchPad for doing so.

What power are we talking about? And what does "heating up" mean in numbers?

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks, heating to get 40 Degree rise above ambient. so i need to check how much power is required for getting this temperature rise on a standard FR4 board with thin traces.
Also could you please confirm how mosfet switching can be used to control the current assuming that the MCU will either turn on or off the mosfet but how will it vary the current?

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

When using PWM it can handle the power dissipation, but the current is on/off. Or you generate an analog voltage by low pass filter the PWM and use a circuit like this:

Here you can control the current. But I would prefer a FET instead of the NPN.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks i couldn't understand by low pass filter the PWM? Could you please share the link of the circuit you sent for current control?

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

PWM DAC

For the circuit you can google for "dummy load", it is pretty much the same.

But before now starting with this approach...is this what you want? There was so little information, I just threw in a few things that came to mind.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

i actually want to use MSP430 boards as can't bring up a new board for this experiment which has 8mil traces . I have only this with me as of now. So using an ob board resistor will be helpful . There are many resistors on launchpad can any of those be used ?

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

How do you want to regulate the current through a resistor that sits in a circuit.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

any means which can help to incrementally increase the power will be fine, like say inreasing the voltage across the resistor linearly

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

Sure increasing the voltage across the resistor will increase the power dissipation, but how do you want to raise the voltage on a resistor that is included into a running circuit?

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

that is what i am requeting for -if there is any such resistor acorss which voltage can be varied?

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

No, there isn't.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

Hi can anyone let me know what is the trace width of the trace connecting R32 to LED2 on MSP-EXP430G2 Launchpad.

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

You can download the design files of the LaunchPad on the product website.

It is 12 mil.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

ok thanks and how can i get the copper thickness used on the board i mean how many ounce ?

0 SIDDHARTH MOHAN over 9 years ago in reply to SIDDHARTH MOHAN

Genius 3205 points

any feedback on the copper thickness used on msp430 exp430g2 board

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

I would guess it is 1oz standard thickness, but I don't know for sure. Maybe MikeS knows?

Dennis

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks how can i check what is the copper pad size used for R26 smd 0402 after opening the .brd file in eagle? i tried using dimension command but that is not letting me select the pad properly for getting its size

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

You can export a library from the design files. There is an ULP for this: exp-project-lbr.ulp

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

so i need to search for exp-project-lbr.ulp on web as i don't have it ?

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

It is included in EAGLE.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks i tried to search but couldn't find exp-project-lbr.ulp in either ULP folder or under the Eagel installation folder , can you please confirm the path

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks for the details but as i mentioend in my last comment i tried to search but couldn't find exp-project-lbr.ulp in ULP folder, could you please share the same? regards

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

exp-project-lbr.zip

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

thanks

0 MikeS over 9 years ago in reply to Dennis Eichmann

TI__Expert 7125 points

Yes this is 1 oz thickness

0 SIDDHARTH MOHAN over 9 years ago in reply to MikeS

Genius 3205 points

THANKS Mike, i think there are no separate GND & Power planes on msp-exp430g2 launchpad board? There are only 2 layers on the top & bottom where the copper pour is connected to GND
is it correct?

0 MikeS over 9 years ago in reply to SIDDHARTH MOHAN

TI__Expert 7125 points

Yes this is correct. Just GND pours on the top and bottom layers

0 SIDDHARTH MOHAN over 9 years ago in reply to MikeS

Genius 3205 points

thanks Mike can you please also confirm the thickness of this board? is it FR4 or FR5 pcb substrate?

0 MikeS over 9 years ago in reply to SIDDHARTH MOHAN

TI__Expert 7125 points

It is FR4

0 SIDDHARTH MOHAN over 9 years ago in reply to MikeS

Genius 3205 points

thanks 1.5 mm or 1.6mm FR4? also i would request your advise over " how to increase temperature rise of a SMT resistor by varying the power through it, any suggestions on how can this be achieved using this launchpad? it would be nice if that SMT is on the board itself"

0 MikeS over 9 years ago in reply to SIDDHARTH MOHAN

TI__Expert 7125 points

I am unsure of which FR4 it is. I couldn't even tell you if it is the same across all G2 LPs or not unfortunately.

In terms of your specific end goal, I am afraid I don't have any good suggestions. It might be easier for you to purchase a separate resistor so you know all the detailed specs of it. You may also want to purchase a resostor that has a lower power rating so the temperature will increase easier. What is the reason for increasing the temperature of the resistor?

0 SIDDHARTH MOHAN over 9 years ago in reply to MikeS

Genius 3205 points

can anyone please let me know the make of R26 & R32 on MSP-EXP430G2 Launchpad. i need to get its datasheet . regards

0 SIDDHARTH MOHAN over 9 years ago in reply to SIDDHARTH MOHAN

Genius 3205 points

Request feedback from anyone over the previous query

0 MikeS over 9 years ago in reply to SIDDHARTH MOHAN

TI__Expert 7125 points

We allow our manufacturers to change out parts to mostly equivalent parts, so whatever is in the BOM online may not necessarily be the exact resistor on the PCB. That is why I recommend you purchase your own resistor to populate so you know the exact specifications.

If you just have a general inquiry to the specs, visit ti.com/tool/msp-exp430g2 for the hardware design files.

0 SIDDHARTH MOHAN over 9 years ago in reply to MikeS

Genius 3205 points

thanks for the reply but the make of the SMT resistors is not mentioned in the BOM hence requesting to let me know the make for R26 & R32

0 Dennis Eichmann over 9 years ago in reply to SIDDHARTH MOHAN

Guru 74080 points

As Mike already mentioned, parts like resistors or capacitors are often chosen by the manufacturer of the board. As long as they meet the specifications given by the customer, the used parts can be different for every order of new boards. The manufacturer will take the parts that are the cheapest ones at the moment of the order or he will take parts that he has in stock himself.

0 SIDDHARTH MOHAN over 9 years ago in reply to Dennis Eichmann

Genius 3205 points

can anyone please share or let me know how to generate the IDF file for launchpad pcb. i need to use it in solid modeling.

0 SIDDHARTH MOHAN over 9 years ago in reply to SIDDHARTH MOHAN

Genius 3205 points

Request feedback over the below -

can anyone please share or let me know how to generate the IDF file for launchpad pcb. i need to use it in solid modelling.

0 SIDDHARTH MOHAN over 9 years ago in reply to SIDDHARTH MOHAN

Genius 3205 points

can someone please let me know from where can i get the .lib / .emp / file for launchpad

0 SIDDHARTH MOHAN over 9 years ago in reply to SIDDHARTH MOHAN

Genius 3205 points

Hello All, i need to know what is the plating thickness of the via on launchpad board on trace connected to R14 resistor, attached image

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