ZHCSB85F November 2011 – October 2021 TPS62140 , TPS62140A , TPS62141 , TPS62142 , TPS62143
PRODUCTION DATA
The TPS6214x can be used as inverting power supply by rearranging external circuitry as shown in Figure 9-42. As the former GND node now represents a voltage level below system ground, the voltage difference between VIN and VOUT has to be limited for operation to the maximum supply voltage of 17V (see Equation 16).
Figure 9-42 –3.3V Inverting Power SupplyThe transfer function of the inverting power supply configuration differs from the buck mode transfer function, incorporating a Right Half Plane Zero additionally. The loop stability has to be adapted and an output capacitance of at least 22μF is recommended. A detailed design example is given in Using the TPS6215x in an Inverting Buck-Boost Topology Application Report.