UC3844B, UC3845B, UC2844B, UC2845B
V
V
in
CC
7(12)
5.0V Ref
+
−
7(11)
+
The addition of the RC filter will eliminate
instability caused by the leading edge spike
on the current waveform.
−
Q1
T
6(10)
5(8)
S
R
Q
3(5)
R
Comp/Latch
C
R
S
Figure 24. Current Waveform Spike Suppression
V
V
in
CC
I
B
7(12)
+
0
V
in
Base Charge
Removal
5.0V Ref
−
+
−
C1
+
−
7(11)
R
Q1
g
Q1
6(10)
T
6(10)
S
R
Q
5(8)
3(5)
5(8)
3(5)
Comp/Latch
R
S
R
S
Series gate resistor R will damp any high frequency
g
The totem pole output can furnish negative base current
for enhanced transistor turn−off, with the addition of
capacitor C .
parasitic oscillations caused by the MOSFET input
capacitance and any series wiring inductance in the
gate−source circuit.
1
Figure 25. MOSFET Parasitic Oscillations
Figure 26. Bipolar Transistor Drive
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