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The L99ASC03 current sense amplifier circuit

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The L99ASC03 current sense amplifier circuit

The L99ASC03 current sense amplifier consists of two stages. The first stage is a fixed gain

of 10 inverting amplifier. The second stage is a programmable gain inverting amplifier. The

10. This translates to system gain settings of 20, 30, 70 and 100 when considering both op-

amps.

Figure 1. L99ASC03 current sense amplifier circuit

Where:

•

As a result ratios stay fairly tight)

•

With both the CSI+ and CSI- pins available we can add a few resistors to the CSI- pin to

generate an appropriate offset to bring the CSO @ 0 A to close to 0 V.

Figure 2. L99ASC03 input offset circuit

GAPG2002140828MS