TPS2384EVM - Capacitance Measurement is not happening

Jothiganeshan Mylsamy

Prodigy 80 points

Other Parts Discussed in Thread: TPS2384

I am having TPS2384 HPA109 evaluation module (EVM) and Running TPS2384 GUI in my laptop.

I am able to get proper result in GUI for all commands.

But "Capacitance" command is not working for me.

I am writing Capacitance command. Then, i am reading. Now "Volts Legacy" should have some value.

But "Volts Legacy" is not getting updated.

Note 1: All other commands are working as expected.

Note 2: TPS2384 is in Power managed mode.

over 14 years ago

0 Eric Wright over 14 years ago

TI__Mastermind 42795 points

We'll take a look at this

0 Eric Wright over 14 years ago in reply to Eric Wright

TI__Mastermind 42795 points

Please try this procedure on the EVM using the TI GUI:

1. Hook up the legacy PD to the EVM port under test. Alternatively, hook up a capacitor with a light load resistance of 5-10kohm across the port.

2. For the port under test (port 2 in this case), select the Capacitance function from the drop down menu, then click the appropriate port # to Write the function command.

3. Select the Ramp Up function from the drop down menu and Write the command. Click the Read button to refresh the port readings.

4. Volts running and volts legacy will be displayed along with voltage raw containing the legacy voltage count reading for the port under test.

5. Use the voltage raw reading (count) along with figure 13 in the TPS2384 datasheet to find the measured capacitance.

0 Jothiganeshan Mylsamy over 14 years ago in reply to Eric Wright

Prodigy 80 points

Yes, As per your procedure, i can able to measure capacitance.

But, why do we need to write Ramp Up function?

Because of Ramp Up function, My PD is powered.

I need to measure capacitance of PD without powering it.

0 Eric Wright over 14 years ago in reply to Jothiganeshan Mylsamy

TI__Mastermind 42795 points

I agree, you should be able to measure capacitance without ramp up. Our GUI engineer will look into this.

0 Eric Wright over 14 years ago in reply to Eric Wright

TI__Mastermind 42795 points

We believe that the EVM GUI (which you downloaded from the TI web site) is masking the correct operation of the capacitance function (IE the funtion worked properly but the result is not displayed in the GUI fields).

Please try the attached GUI update and follow the short instructions in the attached document. I am able to display the voltage fields when writing the "Legacy" function followed by a GUI Read.

Legacy capacitance calculation using TPS2384.zip

0 Jothiganeshan Mylsamy over 14 years ago in reply to Eric Wright

Prodigy 80 points

When i try to run "TPS2384 EVM 14-08-2006.exe" ,i am getting error message "TPS2384 EVM has encountered a problem and needs to close".

I think, you have to send "setup file" for installation.

0 Eric Wright over 14 years ago in reply to Jothiganeshan Mylsamy

TI__Mastermind 42795 points

Sorry for the problem. I just installed the TPS2384EVM GUI on a new PC and had to perform the following steps in order to get TPS2384 EVM 14-08-2006.exe to work.

1. Co-locate TPS2384 EVM 14-08-2006.exe in the same directory as TPS2384 EVM.exe (probably C:\Program Files\Texas Instruments\TPS2384 EVM). This assumes that you already ran the TPS2384EVM GUI setup.exe file when you downloaded the EVM GUI. The updated GUI can use the same system files as the EVM GUI

2. Co-locate the attached text file (TPS2384 EVM 14-08-2006) in the same directory with TPS2384 EVM 14-08-2006.exe (I did not give you this text file yesterday and that is what is preventing the GUI from working).

TPS2384 EVM_081406.zip