JAJSMF7B april 2022 – june 2023 TPS25981
PRODUCTION DATA
Applications which need higher steady current can use two TPS25981xx devices connected in parallel as shown in Figure 9-10 below. In this configuration, the first device turns on initially to provide the inrush current limiting. The second device is held in an OFF state by driving its EN/UVLO pin low using the PG signal of the first device. After the inrush sequence is complete, the first device asserts its PG pin high and turns on the second device. The second device asserts its PG signal to indicate when it has turned on fully, thereby indicating to the system that the parallel combination is ready to deliver the full steady-state current.
Once in steady-state, both devices share current nearly equally. There can be a slight skew in the currents depending on the part-to-part variation in the RON as well as the PCB trace resistance mismatch.
The waveforms below illustrate the behavior of the parallel configuration during start-up as well as during steady-state.
Another way to increase current handling capability of the eFuse in steady-state is by connecting a TPS25981xx eFuse in parallel with a TPS22811x load switch as shown in Figure 9-6.