MC34071,2,4,A MC33071,2,4,A
Figure 49. Low Input Voltage Comparator
with Hysteresis
VO
Hysteresis
R2
Vref R1
VOH
+
MC34071
–
VOL
Vin
R1
VinL = R1+R2 (VOL–Vref)+Vref
R1
VinH = R1+R2 (VOH–Vref)+Vref
R1
VH = R1+R (VOH –VOL)
Vin
VinL VinH
Vref
Figure 50. High Compliance Voltage to
Sink Current Converter
Iout
Vin
+
MC34071
–
Iout =
Vin±VIO
R
R
Figure 51. High Input Impedance
Differential Amplifier
R1
R2
R4
– 1/2
R3
MC34072
– 1/2
VO
+V1
+
MC34072
+
+V2
R2 = R4 (Critical to CMRR)
R1 R3
VO = 1
+ R4
R3
V2–V1 R4
R3
For (V2 ≥ V1), V > 0
Figure 53. Low Voltage Peak Detector
Vin
+
MC34071
–
VO = Vin (pk)
+
RL
VP 10,000 pF
Vin
VP
t
Figure 52. Bridge Current Amplifier
+Vref
RF
R
R
R = ∆R
R
–
VO
MC34071
+
∆R < < R
RF
RF > > R
VO
=
Vref
∆R RF
2R2
(VO ≥ 0.1 V)
Figure 54. High Frequency Pulse
Width Modulation
^ fOSC 0.85
RC V
+ IB
+
ISC
VP 0
t
t
–
Base Charge
Removal
– 1/2 R
MC34072
C
+
V+
100 k
100 k
47 k
Iout
+ 1/2
MC34072
– ±IB
VP
Pulse Width
Control Group
OSC
Comparator
High Current
Output
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