LPV7215MFX INTERSIL [Intersil Corporation], LPV7215MFX Datasheet - Page 16

• Manufacturer Part Number: LPV7215MFX
• Description: Micropower, CMOS Input, RRIO, 1.8V, Push-Pull Output Comparator
• Manufacturer: INTERSIL [Intersil Corporation]

www.national.com
Consider the output of Figure 10 to be high to analyze the
circuit. That implies that the inverted input (V
the non-inverting input (V
through R
the non-inverting input. The value of V
If R
At this point the comparator switches pulling down the output
to the negative rail. The value of V
If R
The capacitor C
V
parator switches again, bringing it back to the initial stage. The
time period is equal to twice the time it takes to discharge
C
the formula for the frequency is:
F = 1/(2·R
WINDOW DETECTOR
A window detector monitors the input signal to determine if it
falls between two voltage levels.
The comparator outputs A and B are high only when
V
where these are defined as
Others names for window detectors are: threshold detector,
level detectors, and amplitude trigger or detector.
C
1
REF1
decreases until it is equal to V
from 2V
1
1
= R
= R
< V
2
2
IN
4
= R
= R
4
, and the voltage V
·C
CC
< V
1
/3 to V
V
3
3
·ln2)
REF2
then V
then V
REF2
1
V
now discharges through R
REF1
= (R
CC
“or within the window.”
A1
A2
/3, which is given by R
= R
2
= 2V
= V
A
+R
). This causes the C
3
/(R
CC
3
)/(R
CC
1
/3
C
+R
/3
increases until it is equal to
1
A2
+R
2
A
+R
, at which point the com-
at this point is
2
+R
3
A
) * V
at this point is
3
) * V
4
+
, and the voltage
C
4
1
+
) is lower than
C
to be charged
1
·ln2. Hence
16
FIGURE 12. Window Detector Output Signal
FIGURE 11. Window Detector
20123647
20123648