Random chopper control circuit

Patent metadata

Field	Value
Publication number	US-9705455-B2
Application number	US-201615041429-A
Country	US
Kind code	B2
Filing date	Feb 11, 2016
Priority date	Mar 3, 2015
Publication date	Jul 11, 2017
Grant date	Jul 11, 2017

Abstract

A random chopper control circuit is disclosed. The random chopper control circuit is coupled to an operational amplifier. The random chopper control circuit includes a random generator. The random generator is configured to generate a random chopper control signal and output the random chopper control signal to the operational amplifier to control an operation of the operational amplifier.

First claim

The invention claimed is:

1. A random chopper control circuit coupled to an operational amplifier, the random chopper control circuit comprising:
a random generator configured to generate a random chopper control signal and output the random chopper control signal to the operational amplifier to control an operation of the operational amplifier;
wherein the operational amplifier comprises:
a first exchanging unit coupled to the random generator;
a first stage amplifying unit coupled to the first exchanging unit and the random generator;
a second exchanging unit coupled to the first stage amplifying unit; and
a second stage amplifying unit coupled to the second exchanging unit, the first exchanging unit and the random generator.

2. The random chopper control circuit of claim 1 , wherein the random generator generates the random chopper control signal having a random sequence according to a random algorithm.

3. The random chopper control circuit of claim 1 , wherein the first exchanging unit, the first stage amplifying unit and the second stage amplifying unit receive the random chopper control signal outputted by the random generator respectively.

4. The random chopper control circuit of claim 3 , wherein when the first exchanging unit receives an input signal and receives a first output signal from an output terminal of the second stage amplifying unit, the first exchanging unit selectively exchanges the input signal and the first output signal according to the random chopper control signal and then outputs the first output signal and the input signal to a positive input terminal and a negative input terminal of the first stage amplifying unit respectively.

5. The random chopper control circuit of claim 4 , wherein when the first stage amplifying unit receives the first output signal and the input signal, the first stage amplifying unit amplifies the first output signal and the input signal according to the random chopper control signal and outputs a first amplified signal and a second amplified signal to the second exchanging unit respectively.

6. The random chopper control circuit of claim 5 , wherein the second exchanging unit selectively exchanges the first amplified signal and the second amplified signal and then outputs the second amplified signal and the first amplified signal to a positive input terminal and a negative input terminal of the second stage amplifying unit respectively.

7. The random chopper control circuit of claim 6 , wherein when the second stage amplifying unit receives the second amplified signal and the first amplified signal, the second stage amplifying unit amplifies the second amplified signal and the first amplified signal according to the random chopper control signal and then outputs a second output signal.

Assignees

• Raydium Semiconductor Corp

Inventors

• Huang Chih-Chuan
• Lin Wen-Tsung

Classifications

• H03F3/45475

  using IC blocks as the active amplifying circuit · CPC title

• H03F2203/45212

  the differential amplifier being designed to have a reduced offset · CPC title

• H03F2200/129

  there being a feedback over the complete amplifier · CPC title

• H03F3/45744

  by offset reduction · CPC title

• H03F3/387 Primary

  with semiconductor devices only · CPC title