Hi!

I have 4 questions about ADUM3223/4223.

I want to calculate the power consumption exactly

because our system 's power consumtion would be high

so we want to decide which to use ADUM3223 or ADUM4223.

(1)====================================================================

I made a document to calculate the power consumption.

Could you tell me the way to think about this are correct or not?

***I attach a document.***

And I also understand that the power consumtion at the control curcuit

will be low compared with driver part.

But I want to calculate power consumtion at the control curcuit too.

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(2)====================================================================

At the data sheet Rev.E,

IDDO=(IDDO(D) + (0.5) * CLVDDO) * (2f - fr) + IDDO(Q) from P.17

What is "CLVDDO"?

Is it typo?

Is it "CL * VDDO" ?

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(3)====================================================================

At the data sheet Rev.F P17,

What is RDSON_P and RDSON_N?

Is it the On-Resister at P-MOS and N-MOS in the ADUM3223?

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(4)====================================================================

At the data sheet Rev.F P17,

Why do you double the PDISS_IC?

Because ADUM3223 has two channel?

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Thank you.

Best regards.

Kawa

Hello Kawa,

(1) The internal quiescent power losses will usually be small compared to the switching of the external load, but it can be accounted for by looking at the quiescent current maximums in the datasheet. A conservative value is to add:

Idd1(q) * VDD1 (q) + IddA(q) * VDDA (q) +IddB(q) * VDDB (q)

To the total power dissipation.

(2) Yes, this should read CL * VDDO. The equations found in Rev E relate more to the data converters, and not the gate drivers. Those equations assume the output load is small, but for gate drivers, the overriding factor is the switch capacitance.

(3)RDSON_N is the NMOS resistance, and RDSON_P is the PMOS resistance when on. For the ADuM3223, the typical value is 1.1 Ω and 0.6 Ω. The maximums are written as 3.0 Ω, but this is a conservative value, and the actual values are probably less in application. Using 3.0 Ω will give a worst case scenario for power consumption.

(4) Yes, the power is doubled because there are two channels. If only one channel is being used, you can ignore the factor of 2.

RSchnell