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Digital Electronics
Q 3
R 3
R 1
Q 2
Q 1
D 1
I OL
Q 4
+V CC
+V CC
I IL
Driving Gate
Driven Gate
(a)
Q 3
R 2
R 1
Q 2
Q 1
D1
Q 4
+V CC
+V CC
Driving Gate
Driven Gate
I IH
R 3
I OH
(b)
Figure 5.7 (a) Current sinking action and (b) current sourcing action.
5.3.1.2 Totem-Pole Output Stage
Transistors Q 3 and Q 4 constitute what is known as a totem-pole output arrangement. In such an
arrangement, either Q 3 or Q 4 conducts at a time depending upon the logic status of the inputs. The
totem-pole arrangement at the output has certain distinct advantages. The major advantage of using
Digital Electronics
Q 3
R 3
R 1
Q 2
Q 1
D 1
I OL
Q 4
+V CC
+V CC
I IL
Driving Gate
Driven Gate
(a)
Q 3
R 2
R 1
Q 2
Q 1
D1
Q 4
+V CC
+V CC
Driving Gate
Driven Gate
I IH
R 3
I OH
(b)
Figure 5.7 (a) Current sinking action and (b) current sourcing action.
5.3.1.2 Totem-Pole Output Stage
Transistors Q 3 and Q 4 constitute what is known as a totem-pole output arrangement. In such an
arrangement, either Q 3 or Q 4 conducts at a time depending upon the logic status of the inputs. The
totem-pole arrangement at the output has certain distinct advantages. The major advantage of using