SLVSEQ0A May 2019 – March 2020 TPS54A24
PRODUCTION DATA.
The voltage reference system produces a precise ±0.85%, 0.6-V voltage reference over temperature by scaling the output of a temperature stable band gap circuit. The output voltage is set with a resistor divider from the output (VOUT) to the FB pin shown in Figure 26. TI recommends using 1%-tolerance or better divider resistors. Start with a fixed value for the bottom resistor in the divider, typically 5.1 kΩ or less, then use Equation 1 to calculate the top resistor in the divider. If the values are too high the regulator is more susceptible to noise and voltage errors from the FB input current are noticeable. If the values too high and if switching stops after low-side reverse current limit trips or when in thermal shutdown, bias current out of the SW pin can charge up the output voltage. Using 5.1-kΩ bottom resistance or less prevents the bias current out of the SW pin from charging the output voltage above the set value. Larger resistance may be used if his bias current is accounted for. The minimum output voltage and maximum output voltage can be limited by the minimum on time of the high-side MOSFET and bootstrap voltage (BOOT-SW voltage), respectively.