PGA411Q1EVM: Not connecting to GUI

Manuel Ahumada

Part Number: PGA411Q1EVM

Hi,

I am trying to connect the PGA411-Q1 EVM to the PGA41x-Q1 EVM GUI and there are a couple of things that I cannot seem to make it work. First, when I plug in the USB cable to my computer, the USB_RDY LED is constantly in a blinking state (I power on the device with 5VDC before I plug in the USB). There are random times when I can get the LED to stay solid, but when I do, the next problem happens; the GUI usually reads "Connection Status: connected" and "PGA41x-Q1 Device: Not Available." Based on the user manual, this makes me seems like the board isn't connecting. Every once in a while (totally random set of circumstances) the board will connect, and I get a status of "PGA41x-Q1 Device: Revision V111,11," which seems slightly odd. What can I do to make this work?

On top of that, when I probe the across the OE1 and OE2 pins, I don't see any excitation frequency.

If you have any advice, I would really appreciate it.

Thanks,

Manuel

over 5 years ago

0 Clancy Soehren over 5 years ago

TI__Mastermind 23810 points

Manuel,

There is a trick to the EVM.

If the USB_RD LED is blinking, press the MCU_RST button until the LED is solid
- It will take a couple of seconds after pressing the reset button until the LED will stay solid. It might take a couple of tries in some cases.
- If you wait too long, the LED will start blinking again.
Immediately after the LED is solid, launch the GUI.

You should be seeing Revision v11.1 for the "PGA41x-Q1 Device" and 2.6.5.53 for the "USB Firmware" field.

If you don't have a resolver sensor connected, then the PGA411 will report a fault condition and you will not see anything on OE1 and OE2. Try holding the FAULTRES button on the EVM while monitoring OE1/OE2. Once you have the GUI working, you can also control the FAULTRES pin from the main page or the "Pin Configurations" page.

0 Manuel Ahumada over 5 years ago in reply to Clancy Soehren

Prodigy 80 points

Hi Clancy,

What a trick! I'll give this a shot and report back. Just to be clear, if I don't have the resolver connected, I can hold the FAULTRES button and I should see the excitation frequency across OE1/OE2?

Side question: What current should the EVM board be drawing? I notice that the PGA411-Q1 chip immediately gets hot to the touch when I connect it to 5VDC. The board draws 0.98 Amps from my supply (seems high).

Thanks,

Manuel

0 Clancy Soehren over 5 years ago in reply to Manuel Ahumada

TI__Mastermind 23810 points

Manuel,

That current is much too high! It should be drawing less than 100mA if no sensor is connected. Can you double check that all of your jumper settings match what we suggest in the user's guide?

And yes, you can hold the FAULTRES button and you should see OE1/OE2 start to work. However, you should fix the high current draw problem before trying that.

0 Manuel Ahumada over 5 years ago in reply to Clancy Soehren

Prodigy 80 points

Clancy,

Yeah, 100 mA sounds way more reasonable... Yeah, the jumpers are in the correct positions per the user manual. Maybe a short? Any obvious place I can check for that?