ZHCSHE9J June 2010 – January 2018 TPS7A80
PRODUCTION DATA.
8.2.2 Detailed Design Procedure
The voltage on the FB pin sets the output voltage and is determined by the values of R1 and R2. The values of R1 and R2 can be calculated for any voltage using the formula given in Equation 2:
Equation 2. 
Sample resistor values for common output voltages are shown in Table 1. In Table 1, E96 series resistors are used, and all values meet 1% of the target VOUT, assuming resistors with zero error. For the actual design, pay attention to any resistor error factors. Using lower values for R1 and R2 reduces the noise injected from the FB pin.
Table 1. Sample 1% Resistor Values for Common Output Voltages
| VOUT | R1 | R2 |
|---|---|---|
| 0.8 V | 0 Ω (Short) | Do not populate |
| 1 V | 2.49 kΩ | 10 kΩ |
| 1.2 V | 4.99 kΩ | 10 kΩ |
| 1.5 V | 8.87 kΩ | 10 kΩ |
| 1.8 V | 12.5 kΩ | 10 kΩ |
| 2.5 V | 21 kΩ | 10 kΩ |
| 3.3 V | 30.9 kΩ | 10 kΩ |
| 5 V | 52.3 kΩ | 10 kΩ |