Drain a 3V coin battery with Labview to test the lifetime of the battery?

[blade2008]

I want to simulate/measure the lifetime of a 3V coin battery. This is the circuit which will give the burst to the battery: http://img339.imageshack.us/img339/8206/schematicpicturev2.png The burst is controlled with the CTRL1 and CTRL2 lines with some timing rquirements. One burst is:                 ARM    TX   RX     TX      RX   TX CTRL1           L      H    H      H       H    H CTRL2           H      H    L      H       L    H Length (ms)     3.72   2.6  0.84   4.04    0.8  1 H = 10 V L = 0 V Now I want to drain the battery by applying one Burst gap one Burst gap etc.. The gap should be variable. First I want to use 10 seconds as a gap. I want to draw the battery characteristic. I wanna simulate for example 5 years which should be 1.2 days in the simulation. I have the NI PCI 6221 (37 pin) DAQ card. Can somebody help me to make a VI for this project. The bursts should be in a loop which I should be able to control how long it should run (i.e. 1 day, or 1.5 days) And how I can apply 10 V or 0 V to the CTRL1 and CTRL2 lines in Labview? Thanks in advance.

[aeastet]

Do you have a real time operating system? With the numbers that you supplied you are going to need a real time operating system. You have one of the time less than 1 ms. That would require a real time operating system. That might change how you do the coding a little. Can you confirm the numbers that you have in the image are ms and not seconds. We will also need to know what system you are using to try to simulate the battery life test.

[johnsold]

You might not need a real time operating system if you can program the pulses into a timed digital output.  I do not know whether your device has that capability.  You would only use software timing for the gaps which you indicated were on the order of seconds.

I would change the circuit to put the FET sources on the common line and switch to a FET which can be driven to full conduction with a standard logic signal.  Consider a 2N7000.  Cost is pennies. Drain current is 75 mA at VGS = 4.5 V.

Lynn

[blade2008]

I have Windows XP as my OS and the numbers are in ms not in seconds. My DAQ card is the NI PCI 6221 (37 pin). We can also round up the 0.8 and 0.84 ms to 1 ms. I just dont know how I should control the mosfets with the CTRL1 and CTRL2 lines in labview and how to the timing for the burst signals (ARM then TX then RX then again TX  gain RX and at the end TX). I will use Labview 2010

[blade2008]

Can somebody help me how to drive the CTRL1 and CTRL2 lines with the posted timings to get the burst signal to the battery.  The burst signal should be continuous (while loop I think) with a gap (which should be variable) between each burst signal. I hope somebody can help me because I am very new to Labview and this kind of prorgramming. Still in the learning phase

[Matthew_Kelton]

Your card has 2 clocked digital I/O lines (correlated IO).  You can use those to generate precion pulses.  The issue is they are 5V TTL lines.  So unless you can swap out your MOSFETs, you'll need to add circutiry to convert them to 10V.

Another option may be to use the analog outputs and generate the waveform as a digital line.  They can do 0 - 10V.  You'll need to be careful that you don't accidentally set them to -10V which is possible.

If you can swap out the MOSFETs, I would do that.

Either way, you'll need to setup your pulse, deliver it, and while you are waiting for the next pulse, set it up.  I am assumign that since you have large gaps in the seconds range, that you don't care if they are a little off, and you can get away with a few ms worth of error and just use the system clock or tick count to determine when the next pulse should start.

[blade2008]

Ok I will try to get news MOSFETs. But can you give me a guide how to do everything in Labview (how to program it). I have little knowledge about Labview. I am only into textbased programming languages like Java or C.

Thanks

[Coq_Rouge]

Some FET transistors are made to be TTL signal level compatible. I might compile a list for you if need it.

[wha_x]

Hello wireworkers,

I would like to inform you, that it looks like a lazy student has the wonderful Idea that others will do his homework..................

look at following link in German LabVIEW - Discussion - Forum:

http://www.labviewforum.de/Spannungsmessung-einer-3-V-Batterie-in-einer-Schaltung-t17432.html

He got there  the same answers about the  FET's at wrong position in his schematic   etc.

At least he asks for support - "write the vi for me"  -  " I am a newbe in LabVIEW"  ..... it's your choice - do, whatever you want.

Regards

wha

[Coq_Rouge]

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@blade2008 wrote:

I want to simulate/measure the lifetime of a 3V coin battery. This is the circuit which will give the burst to the battery: http://img339.imageshack.us/img339/8206/schematicpicturev2.png The burst is controlled with the CTRL1 and CTRL2 lines with some timing rquirements. One burst is:                 ARM    TX   RX     TX      RX   TX CTRL1           L      H    H      H       H    H CTRL2           H      H    L      H       L    H Length (ms)     3.72   2.6  0.84   4.04    0.8  1 H = 10 V L = 0 V Now I want to drain the battery by applying one Burst gap one Burst gap etc.. The gap should be variable. First I want to use 10 seconds as a gap. I want to draw the battery characteristic. I wanna simulate for example 5 years which should be 1.2 days in the simulation. I have the NI PCI 6221 (37 pin) DAQ card. Can somebody help me to make a VI for this project. The bursts should be in a loop which I should be able to control how long it should run (i.e. 1 day, or 1.5 days) And how I can apply 10 V or 0 V to the CTRL1 and CTRL2 lines in Labview? Thanks in advance.

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This is a discussion forum. And students are also welcome to ask questions, and have dialog with more experienced people, or people who do know something that you do not know. It is a big difference in asking for help, versus asking for a completed project. But I think blade2008 should have told us this is a school project by him self. It is no reason to hide the fact that you are a student asking for help. Student or not we will still gladly give you push in the correct direction