Output circuit
First Claim
Patent Images
1. An output circuit comprising:
- an operational amplifier;
a current supply circuit which supplies current to said operational amplifier at rising and falling of an output signal from said operational amplifier; and
an impedance changing circuit which changes impedance between said operational amplifier and an output terminal.
4 Assignments
0 Petitions
Accused Products
Abstract
The output circuit is provided with an operational amplifier, a current supply circuit and an impedance changing circuit. The current supply circuit supplies current to the operational amplifiers at rising and falling of an output signal delivered by the operational amplifier. The impedance changing circuit changes the impedance between the operational amplifier and an output terminal.
67 Citations
15 Claims
-
1. An output circuit comprising:
-
an operational amplifier;
a current supply circuit which supplies current to said operational amplifier at rising and falling of an output signal from said operational amplifier; and
an impedance changing circuit which changes impedance between said operational amplifier and an output terminal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
at least one set of second operational amplifier, a bias circuit, a second impedance changing circuit, said second operational amplifier, said bias circuit and said second impedance changing circuit having similar constitutions as those of said operational amplifier, said bias circuit and said impedance changing circuit, respectively; and
a shorting circuit which short-circuits the output terminals of each set.
-
-
6. The output circuit according to claim 2, wherein a capacitive load of a liquid crystal display apparatus is connected to said output terminal.
-
7. The output circuit according to claim 6 further comprising:
-
at least one set of second operational amplifier, a bias circuit, a second impedance changing circuit, said second operational amplifier, said bias circuit and said second impedance changing circuit having similar constitutions as those of said operational amplifier, said bias circuit and said impedance changing circuit, respectively; and
a shorting circuit which short-circuits the output terminals of each set.
-
-
8. The output circuit according to claim 1, wherein said impedance changing circuit has a transfer gate switch connected between said operational amplifier and said output terminal.
-
9. The output circuit according to claim 8, wherein said impedance changing circuit has a control element which controls gate voltages of two field effect transistors constituting said transfer gate switch.
-
10. The output circuit according to claim 9, wherein a capacitive load of a liquid crystal display apparatus is connected to said output terminal.
-
11. The output circuit according to claim 10 further comprising:
-
at least one set of second operational amplifier, a bias circuit, a second impedance changing circuit, said second operational amplifier, said bias circuit and said second impedance changing circuit having similar constitutions as those of said operational amplifier, said bias circuit and said impedance changing circuit, respectively; and
a shorting circuit which short-circuits the output terminals of each set.
-
-
12. The output circuit according to claim 8, wherein a capacitive load of a liquid crystal display apparatus is connected to said output terminal.
-
13. The output circuit according to claim 12 further comprising:
-
at least one set of second operational amplifier, a bias circuit, a second impedance changing circuit, said second operational amplifier, said bias circuit and said second impedance changing circuit having similar constitutions as those of said operational amplifier, said bias circuit and said impedance changing circuit, respectively; and
a shorting circuit which short-circuits the output terminals of each set.
-
-
14. The output circuit according to claim 1, wherein a capacitive load of a liquid crystal display apparatus is connected to said output terminal.
-
15. The output circuit according to claim 14 further comprising:
-
at least one set of second operational amplifier, a bias circuit, a second impedance changing circuit, said second operational amplifier, said bias circuit and said second impedance changing circuit having similar constitutions as those of said operational amplifier, said bias circuit and said impedance changing circuit, respectively; and
a shorting circuit which short-circuits the output terminals of each set.
-
Specification