UCD9090A: UCD9090ARGZT

Hi

It has nothing to do with GUI. 

How about the ADC accuracy on the voltage monitoring? 

Regards

Yihe 

Thanks for the quick response Yihe! Im not sure about ADC accuracy, I cannot monitor voltage rails when it is not set to correct I2C address.

Are you suspecting the 12-bit ADC that reads PMBUS address is getting wrong values? We have two 41.2K at PMBUS_ADD pins (65 Dec is the set address)

When it reads incorrect address through Fusion Digital Power Designer tool, we cannot monitor voltage rails because the configuration requires it to be at address 65 (Dec). These boards are in production and recently there was a failure with almost 10 units. 

Here is the part marking on some of the chips, if it helps:

UCD9090A TI 18I CKLK G4
UCD9090A TI 2AI C2P8 G4
UCD9090A TI 06I APPK G4
UCD9090A TI 19I C1NL G4
UCD9090A TI 2AI C2P8 G4
UCD9090A TI 2AI C2P8 G4
UCD9090A TI 24I C04N G4

Hi

I do not follow you.Why the address can limit the monitoring function.

your current/voltage signal is connected to the pin of UCD and it works regardless the address.

How do you program the device: i2C or JTAG?

Regards

Yihe

What I was referring to is we cannot establish I2C communication when chip is set to wrong address and hence we cannot read the values.

But I just measured voltage using Fusion tool, it is reading Address 52d, and ADC readings look normal. For Set voltage of 0.96VDC ADC readings are between 0.98 and 0.94, this is what I read on scope too. 

Hi

Fusion GUI reading is sufficient. You may need check the soldering of the resistor to ensure that they are all good.

Regards
Yihe

Thanks for the suggestion Yihe! 

I have double checked the resistor values, soldering etc, that all look good. 

Hi

How do you program the part, I2C or JTAG?

Regards

Yihe

I2C

Hi

does a ABA swap isolate the issue?

Do you have TI's EVM and it is worth to test the problem unit with it.

Regards

Yihe

Sorry, "ABA" stands for?

Hi

ABA swamp means to swap the ICs on different board to confirm the issue is on IC or board

Regards

Yihe 

Isolated problem with IC.

HI,

Do you use 1% resistor? can i get your schematics?

Could you please put the iC on the TI EVM?

Regards

Yihe

Here is the Schematics, we have been using same circuit in multiple product lines and is already in production for years. 

Part No of Resistor:  RK73H1JTTD4122F, Res, 41.2K, 1/10W, 1%, 0603, KOA

Hi

I would suggest to run the UCD Debug tool and share the result here.

Regards

Yihe

This is password protected, can you share the password?

HI

it is forestln

Regards

Yihe

1804430002.zip

1804430140.zip

Here are the captures from 2 boards (named per board serial no), see how 1804430002 is reading wrong address? 

Hi

Based on your test, the device shall be fine. but address 52d means that it detect the bin 4 instead of bin5.

Is this a brand new device or device has been running for a while?

Could you put the units at TI's EVM to further test?

Regards

Yihe

Sorry, didn't get this "52d means that it detect the bin 4 instead of bin5"

52d = 0x34 = 0b0011 0100

65d = 0x41 = 0b0100 0001

What is bin 4 and bin5?

This is a brand new device, production house assembled these 2 weeks back. 

What test do you suggest after putting it on TI's EVM?

Hi

Just put the IC to the EVM to see whether the EVM can get the correct address.

If it does not, we may need process FA to understand what happen.

BTW, did you purchase this from legal distribution channel?

Regards

Yihe

About the distribution channel; I'm waiting for a response from our assembly house about the purchase date code and supplier of chips. 

Will post an update on testing in EVM once the chips are removed and reworked at assembly house.

Thanks,

-Thomas