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LM2841: Current limit compared to LM2840

user5994550
Prodigy 40 points
Part Number: LM2841
Other Parts Discussed in Thread: LM2840, LM2842

Hi,

we have implemented an inverting power supply design using the LM2840YMK-ADJ by following the guidelines in your application note SLVA317B. This circuit works fine. Our input voltage is +15V and we generate -15V. According to the calculations in the application note I end up with the following maximum output current:

Iclmin = 0.525 // A

Dmax = 0.81 // From datasheet (Y Option = 1.25MHz)

ILripple = 0.25*0.525 // (25% from app note. 30% is an example in the data sheet)

IOmax = (Iclmin - ILripple/2)*(1-Dmax)

IOmax = 0.087

=> Max output current will be 87mA

We are revising the design and want to increase the output current a notch. I am considering the LM2841 for this usage. I do not understand why the LM2841 can claim a higher output current than LM2840? (300mA vs 100mA). The cycle by cycle current-limit is 525mA for both the LM2840 and LM2841? Please explain?