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+V Dn Control, C +V nn Control, C

x ; — x : —

C(H) C(H) C(L)

X(L)-C| >0-X(L) X(H)-T>- X(H) X(L)

LV HV LV HV
x— — x . . x x^——x x— —
Disconnect Transfer Transfer Disconnect
(a) (b)

+V DD Control, C +V nn Control, C

C(H) C(H) C(L) C(L)

X(H) -T/Q- X(L) X(L) -CT>- X(H) X(H) ~Oo- X(L) X(L) -cH>- X(H)

LV HV LV HV
X — * — X • . [>o- X X • • £>c- X X- 1 -
Disconnect Inverting Inverting Disconnect
(0 (d)
FIGURE 3.8
CMOS tri-state drivers, conjugate circuit symbols, and ideal equivalent circuits, (a) Noninverting
tri-state driver with active high control, C. (b) Noninverting tri-state driver with active low control, (c)
Inverting tri-state driver with active high control, (d) Inverting tri-state driver with active low control.

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