LP3873 Datasheet, PDF (13/16 Pages) National Semiconductor (TI) – 3A Fast Ultra Low Dropout Linear Regulators

Application Hints (Continued)
FIGURE 1. Error Flag Operation
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SENSE PIN
In applications where the regulator output is not very close to
the load, LP3876 can provide better remote load regulation
using the SENSE pin. Figure 2 depicts the advantage of the
SENSE option. LP3873 regulates the voltage at the output
pin. Hence, the voltage at the remote load will be the regu-
lator output voltage minus the drop across the trace resis-
tance. For example, in the case of a 3.3V output, if the trace
resistance is 100mΩ, the voltage at the remote load will be
3V with 3A of load current, I_LOAD. The LP3876 regulates the
voltage at the sense pin. Connecting the sense pin to the
remote load will provide regulation at the remote load, as
shown in Figure 2. If the sense option pin is not required, the
sense pin must be connected to the V_OUT pin.
FIGURE 2. Improving remote load regulation using LP3876
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