Using of 2 ganged FBs ADD5211

Dear Sir/Madam,

Our customer is studying with your ADD5211 LED driver.

So I got a question.

1)

Our customer will design with 2FB gang of sink(open drain) pins.

Such as Fig-23 following.

And he will sink the current by FB1+FB2 and FB3+FB4.

Max sink current is 200mA per 1FB.

So in this case, FB1+FB2=200mA+200mA=400mA.

Also FB3+FB4=200mA+200mA=400mA.

Is this correct?

Otherwise should we think the derating as eg;360mA(90%) ?

2)

Can he drive this sink 400mA continuously no problem?

Of course I will comment to put enough heat sink pad on PWB for heat dissipation.

Another comment?

Thanks Kaos