TMP461-SP: current draw during conversion (Max & typ)

Michael T Schneider

Part Number: TMP461-SP
Other Parts Discussed in Thread: TMP461

Team,

I was looking at the TMP461-SP data sheet (and SMD). I don’t seem to be able to determine the Max/Typ. current draw of the part while converting.

Could you point me to this info?

It is needed for thermal analysis for a few of my designs.

I see the Remote sensor source current as well as the Quiescent current for Active conversion, local sensor/remote sensor but am having trouble putting it all together for a total current draw for the device.

Can you help?

over 6 years ago

0 Kirby Kruckmeyer96848 over 6 years ago

TI__Genius 17125 points

Hello Michael,

Since there is only one conversion path and the sensors are not read simultaneously, the worst case will be when the external diode is measured.

0 Michael T Schneider over 6 years ago in reply to Kirby Kruckmeyer96848

TI__Expert 3790 points

What is the worst case current draw for the TMP461 when doing a conversion on that path?

0 Kirby Kruckmeyer96848 over 6 years ago in reply to Michael T Schneider

TI__Genius 17125 points

If you are still asking about the space grade product, TMP461-SP, it is as shown at the bottom of page 5 of the datasheet.

Kirby

0 Michael T Schneider over 6 years ago in reply to Kirby Kruckmeyer96848

TI__Expert 3790 points

I see the Quiescent current for Active conversion remote sensor spec.

Is Quiescent current the wrong name for this spec? I am looking for total current consumption during full operation of the device.

In my understanding IQ is defined as the current drawn by the IC in a no-load and nonswitching but enabled condition. “No load” means that no current leaves the IC to the output.

Is this spec an oxymoron?

i.e. if I spec my board for typical 400uA max 600uA I should never see current higher than this under any condition?

0 Kirby Kruckmeyer96848 over 6 years ago in reply to Michael T Schneider

TI__Genius 17125 points

Hi Michael,

I agree with your comments. Coming from a power background, I would say that Iq isn't even applicable to this type of part. But the definition of Iq has been expanded within the industry and is sometimes even incorrectly used for some power products (in my opinion).

Probably the closest thing to Iq as you and I would define it would be the standby current.

Since this part only has a single supply and the output current is negligible compared to the total operating current, we really can only test and specify the total current of the part during conversion.

0 Michael T Schneider over 6 years ago in reply to Kirby Kruckmeyer96848

TI__Expert 3790 points

Perfect, Thanks Kirby! got confused on the nomenclature

0 Kirby Kruckmeyer96848 over 6 years ago in reply to Michael T Schneider

TI__Genius 17125 points

To me the issue with Iq, it is just like the common, industry wide misuse of "LDO" to denote any kind of linear regulator, even those with dropouts greater than 2.4V. When someone asks for an LDO, you then have to figure out if they really need low drop out or any type of reg will work.

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TMP461-SP: current draw during conversion (Max & typ)