US 2004/0201412 A1 · Source follower, voltage follower, and semiconductor device

Abstract

A source follower in which any one of the following three modes is selected by a plurality of switching elements: a first mode in which a first potential is supplied to a gate of a transistor and an input potential is supplied to a first electrode of a capacitor respectively and a second electrode of the capacitor and a source of the transistor are connected, a second mode in which an input potential is supplied to the first electrode and the gate of the transistor and the second electrode floats, and a third mode in which the first electrode and the gate of the transistor are connected and a potential thereof floats and a second potential is supplied to the second electrode, a drain of the transistor is supplied with a third potential, and a potential of the source of the transistor is supplied to a subsequent circuit.

Claims27

Dependent claims

A source follower comprising:

a transistor;
a capacitor comprising a first electrode and a second electrode;
a constant current supply connected to a source of the transistor;
and
a plurality of switching elements which can select any one of first to third modes,
wherein in the first mode, a first potential is supplied to a gate of the transistor and an input potential is supplied to the first electrode, respectively, and the second electrode and the source of the transistor are connected;
wherein in the second mode, an input potential is supplied to the first electrode, and the gate of the transistor and a potential of the second electrode floats, and
wherein in the third mode, the first electrode and the gate of the transistor are connected, and a potential thereof floats and a second potential is supplied to the second electrode.

5 more elements

A source follower comprising:

a transistor;
a capacitor comprising a first electrode and a second electrode;
a first switching element for controlling a supply of an input potential to the first electrode;
a second switching element for controlling a supply of a first potential to a gate of the transistor;
a third switching element for controlling a connection between the gate of the transistor and the first electrode;
a fourth switching element for controlling a supply of a second potential to the second electrode;
a fifth switching element for controlling a connection between the second electrode and a source of the transistor;
and
a constant current supply connected to the source of the transistor,
wherein the second and third switching elements control a supply of the first potential to the first electrode.

7 more elements

A voltage follower comprising:

an operational amplifier;
a capacitor comprising a first electrode and a second electrode;
a first switching element for controlling a supply of an input potential to the first electrode;
a second switching element for controlling a supply of a first potential to a non-inverted input terminal of the operational amplifier;
a third switching element for controlling a connection between the non-inverted input terminal and the first electrode;
a fourth switching element for controlling a supply of a second potential to the second electrode;
and
a fifth switching element for controlling a connection between the second electrode and an output terminal of the operational amplifier,
wherein the second and third switching elements control a supply of the first potential to the first electrode;
and
an inverted input terminal of the operational amplifier is connected to the output terminal thereof.

8 more elements

Dependencies are inferred from the claim text.

Source follower, voltage follower, and semiconductor device

Life of this patent

Source follower, voltage follower, and semiconductor device

Life of this patent

Abstract

Claims27