MC34071,2,4,A MC33071,2,4,A
Figure 49. Low Input Voltage Comparator
with Hysteresis
Figure 50. High Compliance Voltage to
Sink Current Converter
V
O
Hysteresis
I
out
R2
V
in
V
OH
V
ref R1
+
+
MC34071
–
MC34071
–
V
OL
V
in
V
in
V
V
inH
inL
V
R1
ref
V
inL
=
(V –V )+V
OL ref ref
R1+R2
R
V ±V
R1
in IO
V
inH
=
(V –V )+V
OH ref ref
I
out
=
R1+R2
R
R1
V =
H
(V –V
)
OH OL
R1+R
Figure 51. High Input Impedance
Differential Amplifier
Figure 52. Bridge Current Amplifier
+V
ref
R1
R2
R
F
R4
R
R
–
R3
1/2
–
V
O
–
V
O
MC34072
+
1/2
MC34072
MC34071
+V1
+V2
+
R
+
R = ∆R
R2
R1
R4
R3
∆R R
F
=
(Critical to CMRR)
V = V
ref
O
2
2R
(V ≥ 0.1 V)
R
F
∆R < < R
R > > R
R4
R3
R4
R3
V = 1
O
+
V2–V1
F
O
For (V2 ≥ V1), V > 0
Figure 54. High Frequency Pulse
Width Modulation
Figure 53. Low Voltage Peak Detector
0.85
RC
f
OSC
+
I
B
V
in
+
SC
V
I
+
V = V (pk)
O in
MC34071
V
P
0
–
t
–
Base Charge
Removal
t
+
I
out
R
L
V
P
10,000 pF
R
–
+
1/2
MC34072
1/2
MC34072
C
+
–
±I
B
V
in
V+
100 k
V
P
Pulse Width
Control Group
100 k
V
P
47 k
t
OSC
Comparator
High Current
Output
http://onsemi.com
14