JAJSHS0C March 2019 – March 2021 TPS92682-Q1
PRODUCTION DATA
The input capacitor is required to reduce switching noise conducted through the input terminal and to reduce the input impedance of the LED driver. Equation 25 is used to calculate the required capacitance of CIN ≥ 10 µF to limit peak-to-peak input voltage ripple, ΔvIN(PP), to 20 mV.
Two 4.7-µF, 50-V ceramic capacitors are used in parallel to achieve the combined input capacitance of 9.4 µF. As shown in Figure 8-11, an additional 33-µF 50-V electrolytic capacitor and more ceramic capacitors are also used at the input terminal to further decrease the overshoot and undershoot of VIN during PWM dimming.