UCD90160 and UCD90240

Igal Fridman

Other Parts Discussed in Thread: UCD90240, UCD90160, PTH08T250W

Hello,

We consider to use UCD90160 and UCD90240 devices as power supply controller, particularly sequencing and adjusting voltages power rails (with PTH08T250WAD power module) . The devices will be used to adjust power module voltage in closed-loop manner.

I would like to confirm the following question:

1. We have in our system outputs Sense+ and Sense- for 0.95V rail, which have to be monitored for closed-loop.

a. Do you have any proved of-the-shelf solution for monitoring differential signals w/ mentioned above parts? If yes please provide the suggested solution.

b. If the answer to previous question is "no" , Could you propose the part that can sense/monitor differential sense input?

c. What is the margining mode BW and how one can ensure stability of two control loops (one of power module and second UCD90*)?

2. Except extra pins of UCD90240 (vs. UCD90160) is there any other conceptual difference?

Thank you very much,

Igal

over 9 years ago

0 Zhiyuan Hu over 9 years ago

TI__Genius 9845 points

1. The margining signal must be connected to the FB pin of the controller, after the resistor divider. If there is resistor divider between Sense+/- pins and the FB pin (very likely that way, since the output voltage can go up to 3.6V), the margining method will not work.

2. UCD90240 is based on the same concept and has the same behavior as UCD90160, with enhanced functions, such as more rails, more fault logs, support of GPI fault to shutdown rails, configure monitor pins as voltage/current/temperature, etc.

0 Igal Fridman over 9 years ago in reply to Zhiyuan Hu

Prodigy 70 points

Thank you.

I did not understand the first answer. Could you elaborate? Do you have any examples?

0 Zhiyuan Hu over 9 years ago in reply to Igal Fridman

TI__Genius 9845 points

UCD90xxx sequencers do not have differential input. They are all single ended. I'm not aware of any digital sequencer from TI that has differential input.

The margining method of UCD90xxx likely does not work with the power module. Please refer to this document to see how margining work. The margining circuit must be connected to the FB node of the PWM controller.
www.ti.com/.../slva375b.pdf

Regards,
Zhiyuan

0 Igal Fridman over 9 years ago in reply to Zhiyuan Hu

Prodigy 70 points

PLease confirm, that UCD90xxx will not work with power module PTH08T250WAD.

0 Zhiyuan Hu over 9 years ago in reply to Igal Fridman

TI__Genius 9845 points

Do you have the internal circuitry of PTH08T250WAD? I can take a look.

0 Igal Fridman over 9 years ago in reply to Zhiyuan Hu

Prodigy 70 points

This TI product...
I expect you, as TI employee to have such documents.

1. What did you mean by saying "The margining method of UCD90xxx likely does not work with the power module" above?
2. What is the margining BW of UCD90xxx?

0 Zhiyuan Hu over 9 years ago in reply to Igal Fridman

TI__Genius 9845 points

1. As discussed in this document, www.ti.com/.../slva375b.pdf, the margining circuit must be connected to the FB node of the PWM controller. I believe the power module has a resistor divider after the Sense+/- pins, therefore connecting the margin circuit to the Sense+/- pins will not work. You will need to fly a wire to connect the margin R-C-R circuit and the FB node of the controller on the module.

2. The UCD90xxx adjusts the margin FPWM duty cycle once every 500us. The adjustment step is always 1LSB towards the object voltage level. It is not a filter so it is difficult to specify BW. But it is extremely slow.

0 Igal Fridman over 9 years ago in reply to Zhiyuan Hu

Prodigy 70 points

Hi,

We still need your help.

We expect from TI, as manufacturer of both devices (UCD90xxx and PTH08T250WAD), clear Yes/No answer if the devices are compatible for "Closed-loop margin PWM" operation.

If the answer is "yes", please provide with corresponding required interconnection, methodology, calculation.

Appreciate your help.

Thank you,

Igal

0 Zhiyuan Hu over 9 years ago in reply to Igal Fridman

TI__Genius 9845 points

The PTH08T250WAD cannot be used with UCD90XXX series.

Regards,

Zhiyuan

0 Tom Guerin over 9 years ago in reply to Zhiyuan Hu

TI__Mastermind 38230 points

PTH08T250W is not margin control compatible with UCD control IC.

Tom

0 Igal Fridman over 9 years ago in reply to Tom Guerin

Prodigy 70 points

Thank you.
Igal

Power management

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UCD90160 and UCD90240