US-12620989-B2 - Power supply switch circuit

US12620989B2US 12620989 B2US12620989 B2US 12620989B2US-12620989-B2

Abstract

A power supply switch circuit includes a first switch configured to supply a first power supply voltage to a power supply terminal of a power amplifier, a control voltage generator configured to compare a first voltage of the power supply terminal with a predetermined first reference voltage to generate a first control voltage higher than the first power supply voltage, and a switch controller configured to use the first control voltage to generate a switching driving signal controlling the first switch.

Inventors

Youngwong JANG
JeongHoon Kim
Shinichi Iizuka
Jongok HA
Hyejin Lee

Assignees

SAMSUNG ELECTRO-MECHANICS CO., LTD.

Dates

Publication Date: 20260505
Application Date: 20220712
Priority Date: 20211008

Claims (15)

1 . A power supply switch circuit, comprising: a first switch configured to supply a first power supply voltage to a power supply terminal of a power amplifier; a control voltage generator configured to compare a first voltage with a predetermined first reference voltage to generate a first control voltage higher than the first power supply voltage, wherein the first voltage is a voltage at the power supply terminal; and a switch controller configured to use the first control voltage to generate a switching driving signal controlling the first switch, wherein the switch controller comprises a buffer circuit configured to receive the first control voltage and generate the switching driving signal with the first control voltage.
2 . The power supply switch circuit of claim 1 , further comprising: a second switch configured to supply a second power supply voltage to the power supply terminal, wherein the control voltage generator is further configured to compare the first voltage with a predetermined second reference voltage to generate a second control voltage higher than the second power supply voltage, and the switch controller is further configured to use the second control voltage to generate a switching driving signal controlling the second switch.
3 . The power supply switch circuit of claim 1 , wherein the control voltage generator comprises: a comparator configured to compare the first voltage with the first reference voltage; an oscillator configured to generate a waveform signal in response to an output of the comparator; and a charge pump configured to receive the first power supply voltage, the predetermined second voltage, and the waveform signal to generate the first control voltage.
4 . The power supply switch circuit of claim 3 , wherein the first control voltage is a sum of the first power supply voltage and the second voltage.
5 . The power supply switch circuit of claim 3 , wherein the charge pump is further configured to perform a charge pumping operation until the first voltage becomes the first reference voltage.
6 . The power supply switch circuit of claim 1 , wherein the first power supply voltage is configured to vary based on an envelope of a radio frequency (RF) signal inputted to the power amplifier.
7 . The power supply switch circuit of claim 2 , wherein the first reference voltage is lower than the first power supply voltage, and the second reference voltage is lower than the second power supply voltage.
8 . A power supply switch circuit, comprising: a first switch connected between a first power supply circuit configured to output a first voltage and a power supply terminal of a power amplifier; a second switch connected between a second power supply circuit configured to output a second voltage and the power supply terminal; a control voltage generator configured to generate a first control voltage higher than the first voltage, and a second control voltage higher than the second voltage using a voltage of the power supply terminal, the first voltage, and the second voltage, wherein the voltage of the power supply terminal is a voltage at the power supply terminal; and a switch controller configured to generate a first switching driving signal controlling the first switch using the first control voltage, and generate a second switching driving signal controlling the second switch using the second control voltage, the switch controller comprises a buffer circuit configured to receive the first control voltage and the second control voltage, and generate the first switching driving signal with the first control voltage and the second switching driving signal with the second control voltage.
9 . The power supply switch circuit of claim 8 , wherein the control voltage generator comprises: a first control voltage generator configured to generate the first control voltage using the voltage of the power supply terminal, the first voltage, and a predetermined first reference voltage; and a second control voltage generator configured to generate the second control voltage using the voltage of the power supply terminal, the second voltage, and a second predetermined reference voltage.
10 . The power supply switch circuit of claim 9 , wherein the first control voltage generator comprises: a first comparator configured to compare the voltage of the power supply terminal with the first reference voltage; a first oscillator configured to generate a waveform signal in response to an output of the first comparator; and a first charge pump configured to receive the first voltage, a predetermined third voltage, and an output of the first oscillator to generate the first control voltage.
11 . The power supply switch circuit of claim 10 , wherein the second control voltage generator comprises: a second comparator configured to compare the voltage of the power supply terminal with the second reference voltage; a second oscillator configured to generate a waveform signal in response to an output of the second comparator; and a second charge pump configured to receive the second voltage, a predetermined fourth voltage, and an output of the second oscillator to generate the second control voltage.
12 . The power supply switch circuit of claim 11 , wherein the first control voltage is a sum of the first voltage and the third voltage, and the second control voltage is a sum of the second voltage and the fourth voltage.
13 . The power supply switch circuit of claim 11 , wherein the first charge pump is configured to perform a charge pumping operation until the voltage of the power supply terminal becomes the first reference voltage, and the second charge pump is configured to perform a charge pumping operation until the voltage of the power supply terminal becomes the second reference voltage.
14 . The power supply switch circuit of claim 8 , wherein the first and second voltages vary based on an envelope of a radio frequency (RF) signal inputted to the power amplifier.
15 . The power supply switch circuit of claim 9 , wherein the first reference voltage is lower than the first voltage, and the second reference voltage is lower than the second voltage.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims the benefit under 35 USC 119(a) of Korean Patent Application No. 10-2021-0133791 filed in the Korean Intellectual Property Office on Oct. 8, 2021, the entire disclosure of which is incorporated herein by reference for all purposes. BACKGROUND 1. Field The present description relates to a power supply switch circuit. 2. Description of the Related Art As wireless communication standards evolve, a plurality of communication standards such as 2G, Wi-Fi, Bluetooth, 3G, 4G, and 5G may be used in one device (for example, a smartphone). As the plurality of communication standards are used in one device, a power amplifier for outputting a transmission signal is used for each communication standard. That is, in order to output a signal conforming to the plurality of communication standards, a plurality of power amplifiers corresponding to the plurality of communication standards may be required. The power amplifier operates by receiving power from the outside, and in general, a separate power supply integrated circuit (IC) for supplying power to one power amplifier is used. For example, four power supply ICs are used to operate four power amplifiers. However, when one of the plurality of communication standards is used, another communication standard may not be simultaneously used. For example, when the 4G communication standard is used, the 3G communication standard may not be used. Accordingly, a power supply IC corresponding to the unused communication standard needs to be effectively used for other communication standards. The above information disclosed in this Background section is only for enhancement of understanding of the background of the disclosure, and therefore it may contain information that does not form the prior art. SUMMARY This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. In one general aspect, a power supply switch circuit includes a first switch configured to supply a first power supply voltage to a power supply terminal of a power amplifier, a control voltage generator configured to compare a first voltage of the power supply terminal with a predetermined first reference voltage to generate a first control voltage higher than the first power supply voltage, and a switch controller configured to use the first control voltage to generate a switching driving signal controlling the first switch. The power supply switch circuit may further include a second switch configured to supply a second power supply voltage to the power supply terminal. The control voltage generator may be further configured to compare the first voltage with a predetermined second reference voltage to generate a second control voltage higher than the second power supply voltage. The switch controller may be further configured to use the second control voltage to generate a switching driving signal controlling the second switch. The control voltage generator may include a comparator configured to compare the first voltage with the first reference voltage, an oscillator configured to generate a waveform signal in response to an output of the comparator, and a charge pump configured to receive the first power supply voltage, the predetermined second voltage, and the waveform signal to generate the first control voltage. The first control voltage may be a sum of the first power supply voltage and the second voltage. The charge pump may be further configured to perform a charge pumping operation until the first voltage becomes the first reference voltage. The switch controller may include a buffer circuit configured to receive the first control voltage and generate the switching driving signal with the first control voltage. The first power supply voltage may be configured to vary based on an envelope of a radio frequency (RF) signal inputted to the power amplifier. The first reference voltage may be lower than the first power supply voltage, and the second reference voltage may be lower than the second power supply voltage. In another general aspect, a power supply switch circuit includes a first switch connected between a first power supply circuit configured to output a first voltage and a power supply terminal of a power amplifier; a second switch connected between a second power supply circuit configured to output a second voltage and the power supply terminal; a control voltage generator configured to generate a first control voltage higher than the first voltage, and a second control voltage higher than the second voltage using a voltage of the power supply terminal, the first voltage, and the second voltage; and a switch controller configured to generate a first switchi