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# Current Sensing with LTC2945

Dear Sir I have questions about LTC2945. As the simplified schematic block shown in the data sheet, the delta-Vsense (current sensing) voltage is amplified by 20 and then is converted into digital bits which are stored in the register. The host MCU can read the register and obtain the digital bits, and then MCU needs a equation to convert this digital bits into a current value (current flowing in the external Rsense). However, I can't find this conversion equation in this data sheet. thanks a lot

Parents
• The LSB read back in delta-Vsense is 25uV. You don't need to compensate for the 20x internal amplification yourself, as it is already accounted for in the 25uV value of the LSB.

Current across the shunt can be calculated using Ohm's law: I=V/R.  So if you have 1A across the 0.02Ω shunt, the IC would measure 20mV for delta-Vsense. (delta-Vsense would be roughly 800 in this 1A example, read from IC in binary as 1100100000 and multiplied by 25uV to get the resulting 20mV).

• The LSB read back in delta-Vsense is 25uV. You don't need to compensate for the 20x internal amplification yourself, as it is already accounted for in the 25uV value of the LSB.

Current across the shunt can be calculated using Ohm's law: I=V/R.  So if you have 1A across the 0.02Ω shunt, the IC would measure 20mV for delta-Vsense. (delta-Vsense would be roughly 800 in this 1A example, read from IC in binary as 1100100000 and multiplied by 25uV to get the resulting 20mV).

Children
•  Dear mvrablic