JAJSRU9 October 2023 TMCS1133
ADVANCE INFORMATION
The zero current reference voltage, VREF, along with device sensitivity, S, and supply voltage, VS, determine the linear input current measurement range of the device as listed in the Device ComparisonDevice ComparisonDevice Comparison table. The maximum linear output voltage, VOUT,max, is limited by the exceptional near-to-supply output voltage swing, SwingVS, of the TMCS1133 as defined in the Electrical CharacteristicsElectrical CharacteristicsElectrical CharacteristicsElectrical CharacteristicsElectrical Characteristics table and shown in Equation 16.
The minimum linear output voltage, VOUT,min, is limited by the exceptional near-to-ground linear output swing, SwingGND, as is also defined in the Electrical CharacteristicsElectrical CharacteristicsElectrical CharacteristicsElectrical CharacteristicsElectrical Characteristics table and shown in Equation 17.
Overall maximum dynamic range can be optimized with proper device selection by referring minimum and maximum linear output voltage swing to minimum and maximum linear input current range by dividing output voltage by sensitivity, S (see Equation 18 and Equation 19).
where
As an example for determining linear input current measurement range, consider the TMCS1133A2A, TMCS1133B2A and TMCS1133C2A, all with 50 mV/A sensitivity as shown in the Device ComparisonDevice ComparisonDevice Comparison table. When used with a 5V supply, the TMCS1133A2A has a balanced ±48A bidirectional linear current measurement range about the 2.5V zero current output reference voltage, VREF, as shown in Figure 8-1. When used with a 3.3V supply, the TMCS1133B2A has a balanced ±31A bidirectional linear current measurement range about the 1.65V zero current output reference voltage. If used with a 5V supply, the linear current measurement range of the TMCS1133B2A can be extended from –31 A to +65 A as shown in Figure 8-1. The TMCS1133C2A with a 0.33V zero current reference voltage is intended for measuring unidirectional currents. When used with a 3.3V supply the TMCS1133C2A has a unidirectional linear current measurement range from –5 A to +57 A which can be extended from –5 A to +91.4 A when used with a 5V supply.