SLVSCV5E March 2015 – December 2024 ATL431 , ATL432
PRODUCTION DATA
Though the ATL43x is stable with no capacitive load, the device that receives the output voltage of the shunt regulator could present a capacitive load that is within the ATL43x region of stability, shown in Figure 5-14 through Figure 5-21. Also, designers can use capacitive loads to improve the transient response or for power supply decoupling.
Figure 5-14 through Figure 5-21 should be used as a guide for capacitor selection and compensation. It is characterized using ceramic capacitors with very-low ESR. When it is desirable to use a capacitor within the unstable region, higher ESR capacitors can be used to stabilize ATL43x or an external series resistance can be added. For more information and guidance on ESR values, see Designing with the "Advanced" TL431, ATL431 (SLVA685).
Unlike the TL431, the stability boundary is characterized and determined with resistors 250Ω and greater. Which is designed for low cathode current applications.