US 4,321,428 A · Acoustic monolithic power semiconductor integrated circuit and acoustic system using the same

Abstract

An acoustic monolithic IC, which is enabled by a simple modification of the external circuit thereof to realize either the amplification of the left and right channels of stereophonic signals or the application to a balanced transformer-less (BTL) amplifier circuit, is composed of first and second differential amplifier circuits each having non-inverting and inverting inputs and of first and second amplifier output circuits each having non-inverting and inverting inputs. The first differential amplifier circuit has its non-inverting and inverting inputs led as the first and second input terminals of the acoustic monolithic IC to the outside thereof whereas the second differential amplifier circuit has its non-inverting and inverting inputs led as the third and fourth input terminals of the acoustic monolithic IC to the outside thereof. The output signals of the first and second differential amplifier circuits are impressed upon the non-inverting inputs of the first and second amplifier output circuits, respectively. The inverting inputs of the first and second amplifier output circuits are led as first and second feedback terminals to the outside of the acoustic monolithic IC so as to determine the gains and output DC levels of those amplifier output circuits. The output terminals of the first and second amplifier output circuits are led as the first and second output terminals of the acoustic monolithic IC to the outside thereof.

Claims6

Dependent claims

An acoustic monolithic power semiconductor integrated circuit comprising:

a first differential amplifier circuit having non-inverting and inverting inputs led as first and second input terminals of said integrated circuit to the outside of the same, respectively;
a first amplifier output circuit having a non-inverting input supplied with the output signal of said first differential amplifier circuit within said integrated circuit and an inverting input led as first feedback terminal to the outside of said integrated circuit for determining the gain and output DC level of said first amplifier output circuit, said first amplifier output circuit having its output terminal led as a first output terminal of said integrated circuit to the outside of the same, and further comprising:
a second differential amplifier circuit having non-inverting and inverting inputs led as third and fourth input terminals of said integrated circuit to the outside of the same, respectively;
and
a second amplifier output circuit having a non-inverting input supplied with the output signal of the second-named differential amplifier circuit within said integrated circuit and an inverting input led as a second feedback terminal to the outside of said integrated circuit for determining the gain and output DC level of the second-named amplifier output circuit, the second-named amplifier output circuit having its output terminal led as a second output terminal of said integrated circuit to the outside of the same.

2 more elements

An acoustic monolithic power semiconductor integrated circuit comprising:

a first differential amplifier circuit having non-inverting and inverting inputs led as first and second input terminals of said integrated circuit to the outside of the same, respectively;
a first amplifier output circuit having a non-inverting input and an inverting input, said non-inverting input of said first amplifier output circuit being DC coupled with the output of said first differential amplifier circuit in said integrated circuit, said inverting input of said first amplifier output circuit being connected to a first feedback terminal through a first feedback resistor formed in said integrated circuit and connected to the output terminal of said first amplifier output circuit through a second feedback resistor formed in said integrated circuit, said first feedback terminal being disposed as one external terminal of said integrated circuit, said output terminal of said first amplifier output circuit being led as a first output terminal of said integrated circuit to the outside of the same;
a second differential amplifier circuit having non-inverting and inverting inputs led as third and fourth input terminals of said integrated circuit to the outside of the same, respectively;
and
a second amplifier output circuit having a non-inverting input and an inverting input, said non-inverting input of said second amplifier output circuit being DC coupled with the output of said second differential amplifier circuit in said integrated circuit, said inverting input of said second amplifier output circuit being connected to a second feedback terminal through a third feedback resistor in said integrated circuit and connected to the output terminal of said second amplifier output circuit through a fourth feedback resistor in said integrated circuit, said second feedback terminal being disposed as another external terminal of said integrated circuit, said output terminal of said second amplifier output circuit being led as a second output terminal of said integrated circuit to the outside of the same.

2 more elements

Dependencies are inferred from the claim text.

Acoustic monolithic power semiconductor integrated circuit and acoustic system using the same

Life of this patent

Acoustic monolithic power semiconductor integrated circuit and acoustic system using the same

Life of this patent

Abstract

Claims6