MCP39xx with Current Transformer (CT)

Is is possible to use the MCP39xx metering devices with a current transformer instead of a shunt resistor?

The MCP3901 evaluation board has footprints for current transformers. From the MCP3901 product page, select the "MCP3901 Low-Cost Power Monitor Reference Design User's Guide" under Documents > User Guides.

For MCP3905, see Figure 2-9 in "MCP3905A/6A Evaluation Board User's Guide" under Documents > User Guides.

For MCP39F501/MCP39F511, there are no examples with a CT because the MCP39F501 and MCP39F511 were designed for working with a shunt, which is a cheaper current sensor. Theoretically, a CT should work as well, provided that the correct resistor load is chosen and the voltage at the ADC inputs are kept within the specified limits. The phase error is usually larger for a CT than for a shunt, so this may pose a problem with the phase compensation if it is outside the limits (+/- 3.2°).

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