SBASAJ6B April 2022 – December 2024 AMC22C11
PRODUCTION DATA
The voltage on the REF pin determines the trip threshold of the comparator. The internal precision current source forces a 100μA current through an external resistor connected from the REF pin to GND1. The resulting voltage across the resistor (VREF) equals the trip threshold, see Figure 6-1. Place a 100nF capacitor parallel to the resistor to filter the reference voltage. This capacitor must be charged by the 100μA current source during power-up and the charging time can exceed the high-side blanking time (tHS,BLK). In this case, as shown in Figure 6-2, the comparator can output an incorrect state after the high-side blanking time has expired until VREF reaches the final value. See the Power-Up and Power-Down Behavior section for more details on power-up behavior.
The reference pin can be driven by an external voltage source to change the comparator threshold during operation. However, do not drive VREF dynamically across the VMSEL threshold during normal operation because doing so changes the hysteresis of the comparator and can lead to unintentional switching of the output.
Figure 6-3 shows a mode selection timing diagram.