4 Conclusion

A practical approach to achieve longer hold-up time is proposed in this application report. As it has been confirmed with the actual application case (V_IN = 5 V, V_OUT = 3.3 V, L1 = 1.0 µH, L2 = 3.3 µH, F_S = 1.25 MHz), the solution operates properly having 5 ms longer hold-up time compared to the typical application case of the TPS62130, and a boost pre-regulator without an independent PWM controller is used for achieving longer hold-up time at a reasonable cost. This makes the solution more attractive in terms of the total solution cost. Since V_BOOST.OUT will be the input of the TPS62130, V_BOOST.OUT should be carefully reviewed in terms of its voltage level, and PCB layout is also critical to get the desired results.