SBOSA23D May 2020 – September 2021 TLV9151-Q1 , TLV9152-Q1 , TLV9154-Q1

PRODUCTION DATA

- 1 Features
- 2 Applications
- 3 Description
- 4 Revision History
- 5 Pin Configuration and Functions
- 6 Specifications
- 7 Detailed Description
- 8 Application and Implementation
- 9 Power Supply Recommendations
- 10Layout
- 11Device and Documentation Support
- 12Mechanical, Packaging, and Orderable Information

- PW|14

- PW|14

The transfer function of the circuit in Figure 8-1 is given in Equation 1.

Equation 1.

The load current (I_{LOAD}) produces a voltage drop across the shunt resistor (R_{SHUNT}). The load current is set from 0 A to 1 A. To keep the shunt voltage below 100 mV at maximum load current, the largest shunt resistor is defined using Equation 2.

Equation 2.

Using Equation 2, R_{SHUNT} is calculated to be 100 mΩ. The voltage drop produced by I_{LOAD} and R_{SHUNT} is amplified by the TLV9151-Q1 to produce an output voltage of 0 V to 4.9 V. The gain needed by the TLV9151-Q1 to produce the necessary output voltage is calculated using Equation 3.

Equation 3.

Using Equation 3, the required gain is calculated to be 49 V/V, which is set with resistors R_{F} and R_{G}. Equation 4 is used to size the resistors, R_{F} and R_{G}, to set the gain of the TLV9151-Q1 to 49 V/V.

Equation 4.

Choosing R_{F} as 360 kΩ, R_{G} is calculated to be 7.5 kΩ. R_{F} and R_{G} were chosen as 360 kΩ and 7.5 kΩ because they are standard value resistors that create a 49:1 ratio. Other resistors that create a 49:1 ratio can also be used. Figure 8-2 shows the measured transfer function of the circuit shown in Figure 8-1.