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LTC2992: no sensing current

Hello,

I connected a 0.5 Ohm shunt for measurement of small current (up to 0.1A) with a voltage up to 5V, following the figure  "4c: Derives Power from a Separate Low Voltage Supply" of the chip datasheet. As platform, I am using an ESP32 from Espressif and your lib https://github.com/analogdevicesinc/Linduino/blob/master/LTSketchbook/libraries/LTC2992/

I can read correctly the Sense1+ and Sense2+ voltages through i2c but not the current. Measuring with an amperemeter, the current is correct, but reading the current registers there is 0. I soldered another LTC2992 as replacement but the same problem occurs.

I am using continuous mode; here is the value for CTRLA:

#define CTRLA LTC2992_CONTINUOUS_SENSE_1_2 | LTC2992_OFFSET_CAL_EVERY | LTC2992_MODE_CONTINUOUS

Here is the manufacturing id and ctrla:

manufacturing id and ctrla

All registers settings (first line is ones digit, first column is tens digit):

registers

Here is reading the status (with a voltage of 1.5V on each sense and same current of 50mA):

- on one line the current1 raw registers are printed

- on the next line: adc status, current 1 code (current registers combined), current 1 in [A], sense 1 code, sense 1 in [V], current 2 code (current registers combined), current 2 in [A], sense 2 code, sense 2 in [V]

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