Load

Power

Converter

Sense-

GND

CSP

CS

Current Sharing

Amplifier

TRO

RSO

R

R

R

R

CS

M

CSO

Remote Sense

Driver

LM5080

10:

Sense +

10:

Vou

t

+

Vou

t

-

8R

+VRS -

VSNS

Load

Power

Converter

Sense-

GND

CSP

CS

Current Sharing

Amplifier

TRO

RSO

R

R

R

R

CS

M

CSO

Remote Sense

Driver

LM5080

10:

Sense +

10:

Vou

t

+

Vou

t

-

8R

+VRS -

VSNS

SHR

8R

NRND

LM5080

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SNVS387C – SEPTEMBER 2005 – REVISED MARCH 2013

Provided the current sharing is equal (VRS1=VRS2), the VSNS voltages will remain unchanged. However, any

difference between VRS1 and VRS2 will drive the VSNS1 and VSNS2 voltages in opposite polarities. As a result

the power converter output voltages will be adjusted to force VRS1=VRS2.

A capacitor from TRO to ground will compensate the differential amplifier as well as set the dominant pole of the

current share loop. CTRO should be at least 2 nF to insure stability of the differential amplifier. In some systems

a small resistor (RTRO) in series with CTRO will improve stability of the current share loop by introducing a zero

at high frequencies.

In the remote sense modes, it is essential the CSP pins of all LM5080’s be tied to the exact same location on the

PC board. Any mismatch in the CSP voltages between LM5080’s will contribute to current share errors. As in the

reference adjust mode, the current sense resistors should be located as close to the load as possible to minimize

trace resistance in series with the sense resistors. In the remote sense positive mode, VCC must be biased at

least 2V higher than the output regulation voltage to maintain CSP and CSM in the proper common mode range.

Figure 15. Remote Sense Negative Mode Implementation

Figure 16. Remote Sense Positive Mode Implementation

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