ZHCSJQ0A may 2019 – july 2023 LM5108
PRODUCTION DATA
Some switching power supply applications are extremely noisy. Noise may come from ground bouncing and ringing at the inputs, (which are the HI and LI pins of the gate driver device). To mitigate such situations, the LM5108 offers wide input threshold hysteresis. If these features are not enough, then the application might need an input filter. Small filter such as 10-Ω resistor and 47-pF capacitor might be sufficient to filter noise at the inputs of the gate driver device. This RC filter would introduce delay and therefore need to be considered carefully. High frequency noise on bias supply can cause problems in performance of the gate driver device. To filter this noise it is recommended to use 1-Ω resistor in series with VDD pin as shown in Figure 8-1. This resistor also acts as a current limiting element. In the event of short circuit on the bias rail, this resistor opens up and prevents further damage. This resistor can also be helpful in debugging the design during development phase.