SBVS065L December 2005 – December 2024 TPS74301
PRODUCTION DATA
The TPS743 features a track pin that allows the output to track an external supply at start-up. While the TRACK input is below 0.8V, the error amplifier regulates the FB pin to the TRACK input. Properly choosing the resistor divider network (R1 and R2) as shown in Figure 7-3 enables the regulator output to track the external supply to obtain a simultaneous or ratiometric start-up. Once the TRACK input reaches 0.8V, the error amplifier regulates the FB pin to the 0.8V internal reference. Further increases to the TRACK input have no effect.
Figure 7-3 Various Sequencing Methods Using the TRACK PinThe maximum recommended value for R2 is 100kΩ. Once R2 is selected, R1 is calculated using one of the equations given in Figure 7-3.