ADCMP350/ADCMP354/ADCMP356

Rev. B | Page 9 of 12

APPLICATIONS INFORMATION

ADDING HYSTERESIS

To prevent oscillations at the output caused by noise or slowly

moving signals passing the switching threshold, positive feedback

can be used to add hysteresis to the noninverting parts

(ADCMP354 and ADCMP356).

For the noninverting configuration shown in Figure 20, two

resistors are used to create different switching thresholds,

depending on whether the input signal is increasing or decreasing

in magnitude. When the input voltage is increasing, the threshold is

The upper input threshold level is given by

(

)

PULLUP

CC

PULLUP

R

R2

R1

V

R

R2

R1

+

−

+

+

IN_HI

V

V

The lower input threshold level is given by

(

)

R2

R2

R1

V

V

REF

IN_LO

+

=

The hysteresis is the difference between these voltage levels and

is given by

PULLUP

R

R2

R1

+

=

∆

CC

IN

V

V

ADCMP354

OUT

R2

R1

Figure 20. Noninverting Comparator Configuration with Added Hysteresis

VOLTAGE DETECTOR

The ADCMP350/ADCMP354/ADCMP356 can be used to

monitor voltages, such as battery monitoring or threshold

detectors. Using a resistor divider at the input to select the

appropriate trip voltage, the comparator can be configured

to give a logic output when the input passes that threshold.

Figure 21 shows the typical configuration of the ADCMP354

for monitoring a supply to indicate that the voltage is above a

certain level.

ADCMP354

OUT

R1

R2

Figure 21. Voltage Detector Application