ZHCSI25 April 2018 LMV7239-Q1
PRODUCTION DATA.
7.4.3.1 Inverting Comparator With Hysteresis
The inverting comparator with hysteresis requires a three resistor network that is referenced to the supply voltage V+ of the comparator as shown in Figure 18. When VIN at the inverting input is less than VA, the voltage at the noninverting node of the comparator (VIN< VA), the output voltage is high (for simplicity assume VO switches as high as V+). The three network resistors can be represented as R1//R3 in series with R2.
Figure 18. Inverting Comparator With Hysteresis
The lower input trip voltage VA1 is defined as:
When VIN is greater than VA, the output voltage is low or very close to ground. In this case the three network resistors can be presented as R2 // R3 in series with R1.
The upper trip voltage VA2 is defined as:
The total hysteresis provided by the network is defined as ΔVA = VA1 - VA2.
