Reference Adjustment Operation

voltage reference and feedback divider which do not require

a fast response. In some systems a small resistor (RTRO) in

series with CTRO can improve stability by introducing a zero

at high frequencies to increase the phase margin of the

current share loop.

It is essential that the VCC pins of all LM5080’s be tied to the

same point in this mode. Any mismatch in the VCC voltages

between LM5080’s will significantly contribute to current

share errors. The current sense resistors should be located

as close to the load as possible to minimize trace resistance

in series with the sense resistors which can also contribute

to sharing errors. In this mode, the best accuracy will be

achieved with lower VCC values since any mismatch in the

gain resistors internal to the LM5080 will affect the current

share accuracy.

The effective output current from the TRO pin can be multi-

plied to increase the current share loop gain if necessary. R1

should be at least 10k

Ω.

20157804

FIGURE 1. Reference Adjust Mode Implementation

20157805

FIGURE 2. LM5080 Showing the RSO Buffer Configured to Boost Transconductance

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