SLVSL49 July 2026 LM2903L-Q1
ADVMIX
Configure the circuit as shown in Figure 7-2. Make R1, R2 and R3 each 100kΩ resistors. These three resistors are used to create the positive and negative thresholds for the window comparator (VTH+ and VTH–).
With each resistor being equal, VTH+ is 2.2V and VTH- is 1.1V. Large resistor values such as 100kΩ are used to minimize power consumption. The resistor values can be recalculated to provide the desired trip point values.
The sensor output voltage is applied to the inverting and non-inverting inputs of the two comparators. The two comparator outputs are Wire-OR'ed together.
The respective comparator outputs latches low when the sensor is less than 1.1V or greater than 2.2V. The respective comparator outputs are high when the sensor is in the range of 1.1V to 2.2V (within the "window"), as shown in Figure 7-3.
The CLR pin must be toggled high to low to high to reset the output and arm the window comparator.