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US 9,071,213 B2Granted
Bias circuit and amplifier with current limit function
AssigneeSamsung Electro-Mechanics Co., Ltd.
InventorsShinichi Iizuka, Young Jean Song, Ki Joong Kim, Myeong Woo Han, Ju Young Park, Youn Suk Kim, Jun Goo Won
Life of this patent
Estimating the term…
Abstract
There are provided a bias circuit and an amplifier having a current limit function, including: a control voltage generating unit generating a control voltage using a reference voltage; a bias voltage generating unit generating a bias voltage according to the control voltage; and a bias current limit unit controlling the control voltage according to a bias current of the bias voltage generating unit.
Claims9
A bias circuit comprising:
- a control voltage generating unit generating a control voltage using a reference voltage;
- a bias voltage generating unit generating a bias voltage according to the control voltage;
- and
- a bias current limit unit controlling the control voltage according to a bias current of the bias voltage generating unit to limit an increase in the bias current,
- wherein the control voltage generating unit includes:
- a first temperature compensating transistor having a collector connected to a reference voltage input terminal via a first resistor, and an emitter and a base connected to a ground;
- and
- a second temperature compensating transistor having a collector connected to an operating voltage input terminal, a base connected to the collector of the first temperature compensating transistor, and an emitter connected to the ground via a second resistor,
- wherein the control voltage is provided from the collector of the first temperature compensating transistor, and
- wherein the bias current limit unit includes:
- a current limit resistor reducing a voltage according to the bias current;
- and
- a current limit transistor operated by a voltage difference between the bias voltage and the voltage reduced by the current limit resistor and controlling current flowing through the second temperature compensating transistor.
10 more elements
A bias circuit comprising:
- a control voltage generating unit generating a control voltage using a reference voltage;
- a bias voltage generating unit generating a bias voltage according to the control voltage;
- and
- a bias current limit unit controlling the control voltage according to a bias current of the bias voltage generating unit to limit an increase in the bias current,
- wherein the control voltage generating unit includes:
- a first temperature compensating transistor having a collector connected to a reference voltage input terminal via a first resistor, and an emitter and a base connected to a ground;
- and
- a second temperature compensating transistor having a collector connected to an operating voltage input terminal, a base connected to the collector of the first temperature compensating transistor, and an emitter connected to the ground via a second resistor,
- wherein the control voltage is provided from the collector of the first temperature compensating transistor, and
- wherein the bias current limit unit includes:
- a current limit resistor having one end connected to an output node of the bias voltage generating unit and the other end;
- and
- a current limit transistor having a collector connected to the emitter of the second temperature compensating transistor, a base connected to the other end of the current limit resistor, and an emitter connected to the ground.
10 more elements
An amplifier comprising:
- a control voltage generating unit generating a control voltage using a reference voltage;
- a bias voltage generating unit generating a bias voltage according to the control voltage;
- a bias current limit unit controlling the control voltage according to a bias current of the bias voltage generating unit;
- and
- an amplifying unit receiving the bias voltage from the bias voltage generating unit to amplify a high frequency signal,
- wherein the control voltage generating unit includes:
- a first temperature compensating transistor having a collector connected to a reference voltage input terminal via a first resistor, and an emitter and a base connected to a ground;
- and
- a second temperature compensating transistor having a collector connected to an operating voltage input terminal, a base connected to the collector of the first temperature compensating transistor, and an emitter connected to the ground via a second resistor,
- wherein the control voltage is provided from the collector of the first temperature compensating transistor, and
- wherein the bias current limit unit includes:
- a current limit resistor reducing a voltage according to the bias current;
- and
- a current limit transistor operated by a voltage difference between the bias voltage and the voltage reduced by the current limit resistor and controlling current flowing through the second temperature compensating transistor.
11 more elements
An amplifier comprising:
- a control voltage generating unit generating a control voltage using a reference voltage;
- a bias voltage generating unit generating a bias voltage according to the control voltage;
- a bias current limit unit controlling the control voltage according to a bias current of the bias voltage generating unit;
- and
- an amplifying unit receiving the bias voltage from the bias voltage generating unit to amplify a high frequency signal,
- wherein the control voltage generating unit includes:
- a first temperature compensating transistor having a collector connected to a reference voltage input terminal via a first resistor, and an emitter and a base connected to a ground;
- and
- a second temperature compensating transistor having a collector connected to an operating voltage input terminal, a base connected to the collector of the first temperature compensating transistor, and an emitter connected to the ground via a second resistor,
- wherein the control voltage is provided from the collector of the first temperature compensating transistor, and
- wherein the bias current limit unit includes:
- a current limit resistor having one end connected to an output node of the bias voltage generating unit and the other end;
- and
- a current limit transistor having a collector connected to the emitter of the second temperature compensating transistor, a base connected to the other end of the current limit resistor, and an emitter connected to the ground.
11 more elements
Dependencies are inferred from the claim text.