TL084: TL084 VOH with 5k Load

Collin Wells

Guru 62085 points

Part Number: TL084
Other Parts Discussed in Thread: TLV4172

Posting for FAE:

Hi Collins,

Could your team help provide the peak Output Voltage of TL084 with RL=5k ohm at full temp range like below? A simulation results or test results with RL=5k ohm can both be OK.

Customer is evaluating our TL084 to replace ADTL084. While, the Vom @ 2k ohm can’t meet the spec and the datasheet lacks 5k ohm spec. I tried to use the TINA spice model to do the simulation, but the result is much better than the load curve, which doesn’t match with each other.

If we can’t provide those data on TL084, I think TLV4172 can be an alternative, but the price goes higher. Look forward to your feedback sincerely, many thanks!

over 6 years ago

0 Ron Michallick over 6 years ago

TI__Guru*** 140136 points

Collin,

The image called "like below" didn't come through.

Are the a VCC values and Vout target known?

Here is 10k and 2k data from data sheet.

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ronald,

Thanks for your reply. We've seen the 10k & 2k load Vom curve at all temp range in datasheet.
1. Our customer wants to have the 5k load Vom curve at all temp range?
2. Are we able to provide short-output current?

Those two data can be provided by chip test or simulation.

thanks!
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

Do you have a full part number?
There are two TL084 die designs. There may be small differences.

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ronald,

The full part # should be TL084QDR, thanks!

Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

I recorded high and low drive for a TL084QID sample (VCC = +/-15V).

VOL with 5k load was -12.76V to -13.10V across temperature

VOH with 5k load was +13.49V to +13.59V across temperature

Short current while driving high was 21mA to 36mA across temperature

Short current while driving low was 42mA to 56mA across temperature

I attached the raw data with a few charts.

TL084Q VOL, VOH.xlsx

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ronald,

Thanks a lot for providing the data.

I have one question: how do you get the Vom and short current specs? From one TL084 sample test or by design simulation?

And could you help make a plot like the below curve, please? The plot in excel is not that explicit to read. Many thanks!

thanks,

Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

This was actual lab sample data.

VOH

VOL

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ronald,

Customer is satisfied with the test result. However, this is only from one sample.
To get an estimated data by probability calculation, customer hope we can provide more sample's test data. 6 units is the best.
Could you kindly help on this? Thanks a lot!

regards,
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

I could do five more units, but will not at this time. I don't know the application VOH requirement. If I don't know the reason behind the data request, I won't provide data that may be improperly applied. If a few mili-volts makes or breaks the application then it is time to stop. The data I provided assumes VCC+ is exactly 15V, if the 15V supply varies so will the VOH in a 1:1 ratio. If the application supply isn't 15V then the data is close but not correct. Is the load exactly 5k? Does it terminate to ground? Is there any other load (like feedback).

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ronald,

Totally understand your concern. Currently, I don't have the detailed application schematic of TL084 and I believe the Vom specs @5k is key to ctm. Other specs has already passed the review at customer side.

The Vom test data@5k you provided can also meet the spec, but still need to be more secured. The only one sample data may not be convincing if they take more strict review. Therefore, hope to get another 5 more samples. Let me know if there is other concern.

Many thanks!
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

I'll run 5 more however they will be from the same sample bag, so I expect high level of repeatability

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ronald,

I think it's OK. Really appreciate your help and look forward to your test data. Thanks!

regards,
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

Here is 6 samples from 2 lots. VOH with 5k load.

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ron,

Thank you so much for help providing the data. Just one question, do you have the data for VOL as well? Since I only see VOH plot this time.

I'll check with ctm, whether the plot would be enough. Thanks again!

regards,
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

Only VOH was recorded this time.

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ron,

Do we have the θjc[℃/W] for TL084IDR and TL084QDR? I only see RθjA in datasheet.

Many thanks!

regards,

Bell.

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

Theta JC, top 35.7 C/W (use this when heat sinks are used, almost never)
Theta JB 30.9 C/W
Psi JT 5.7 C/W (use this to get TJ by measurement of top of case temperature, very common)
Psi JB 30.6 C/W

Semiconductor and IC Package Thermal Metrics (Rev. C)
www.ti.com/.../getliterature.tsp

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ron,

Thanks a lot for your information.

By the latest status, customer think the temperature rise of the whole set can be controlled within 85°C, then the cheapest TL084I can also be considered. In that case, Vom and output short current of TL084I is needed.

Could you kindly help provide 6 samples data of Vom and output short current of TL084I like you did on TL084Q, please?

Thanks a lot and look forward to your feedback!

regards,
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

TL084I will have same performance as TL084Q, they are based on the same design.

0 Bell Ye over 6 years ago in reply to Ron Michallick

TI__Intellectual 1135 points

Hi Ron,

Got it. So, their only difference is the temp rating, but other performance like Vom and short current would be the same, correct?

regards,
Bell

0 Ron Michallick over 6 years ago in reply to Bell Ye

TI__Guru*** 140136 points

Bell,

Yes, correct!

Amplifiers

Amplifiers forum

TL084: TL084 VOH with 5k Load