Supply modulator including switched-mode power supplier and transmitting device including the same

Patent metadata

Field	Value
Publication number	US-9843260-B1
Application number	US-201715400414-A
Country	US
Kind code	B1
Filing date	Jan 6, 2017
Priority date	Nov 1, 2016
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

A supply modulator including a first switched-mode power supplier configured to transmit a modulated voltage to an output node in response to an envelope signal, the first switched mode power supplier including: a switching circuit configured to transmit a pulse signal in response to the amplitude of the envelope signal; and a low pass filter configured to generate the modulated voltage by filtering certain frequency band of the pulse signal, the low pass filter comprising a plurality of stages; and a second switched-mode power supplier configured to selectively transmit a compensation current to the output node in response to the current transmitted from the first switched-mode power supplier, wherein each of the plurality of stages of the low pass filter comprises at least one variable impedances.

First claim

What is claimed is:

1. A supply modulator comprising:
a first switched-mode power supplier configured to transmit a modulated voltage to an output node in response to an envelope signal, the first switched-mode power supplier comprising:
a switching circuit configured to transmit a pulse signal in response to an amplitude of the envelope signal; and
a low pass filter configured to generate the modulated voltage by filtering certain frequency band of the pulse signal, the low pass filter comprising a plurality of stages; and

a second switched-mode power supplier configured to selectively transmit a compensation current to the output node in response to a current transmitted from the first switched-mode power supplier,
wherein each of the plurality of stages of the low pass filter comprises at least one variable impedances.

2. The supply modulator of claim 1 , wherein the first switched-mode power supplier further comprises an internal controller, the internal controller configured to control impedances of the at least one variable impedances in response to a frequency information.

3. The supply modulator of claim 2 , wherein the frequency information includes information on a frequency band of a baseband signal corresponding to the envelope signal, and
wherein the internal controller is configured to control the impedances of the at least one variable impedances to widen a bandwidth of a passband of the low pass filter in response to an increase of the frequency band of the baseband signal.

4. The supply modulator of claim 2 , wherein the frequency information includes information of a guard bandwidth between a frequency band of a transmission channel and a frequency band of a reception channel of a Frequency Division Duplex (FDD) scheme, and
wherein internal controller is configured to control the impedances of the at least one variable impedances to narrow a bandwidth of a passband of the low pass filter in response to a narrowing of the guard bandwidth.

5. The supply modulator of claim 1 , wherein the first switched-mode power supplier further comprises an internal controller, the internal controller configured to control a frequency of the pulse signal in response to a frequency information.

6. The supply modulator of claim 5 , wherein the frequency information includes information on a frequency band of a baseband signal corresponding to the envelope signal, and
wherein internal controller is configured to decrease the frequency of the pulse signal in response to a decrease of the frequency band of the baseband signal.

7. The supply modulator of claim 5 , wherein the frequency information includes information of a guard bandwidth between a frequency band of a transmission channel and a frequency band of a reception channel of a Frequency Division Duplex (FDD) scheme, and
wherein internal controller is configured to decrease the frequency of the pulse signal in response to a widening of the guard bandwidth.

8. The supply modulator of claim 2 , wherein the internal controller is further configured to reduce a frequency of the pulse signal in response to a decrease of a passband of the low pass filter.

9. The supply modulator of claim 1 , wherein the plurality of stages of the low pass filter comprises a first stage to n th stage sequentially connected between a pulse input node receiving the pulse signal and the output node, wherein:
a first stage comprising a first impedance element connected between a pulse input node and an internal node of the first stage, and a second impedance element connected between the internal node of the first stage and a ground node; and
a k th stage comprising a third impedance element connected between an internal node of a k−1 th stage and an internal node of the k th stage, and a fourth impedance element connected between the internal node of the k th stage and the ground node,
wherein an internal node of the n th stage is connected to the output node,
wherein at least one of the first, second, third, and fourth impedance elements comprises a variable impedance, and
wherein n is a natural number greater than 1, and k is a natural number greater than 1 and equal or smaller than n.

10. The supply modulator of claim 9 , wherein the first impedance element and the third impedance element each comprise an inductor, and
wherein the second impedance element and the fourth impedance element each comprise at least one of a capacitor and an inductor.

11. The supply modulator of claim 1 , wherein the plurality of stages of the low pass filter comprises:
a first stage comprising a first inductor connected between a pulse input node receiving the pulse signal and an internal node, and a first capacitor connected between the internal node and a ground node; and
a second stage comprising a second inductor connected between the internal node and the output node, and a second capacitor connected between the output node and the ground node,
wherein at least one of the first inductor, the first capacitor, the second inductor, and the second capacitor comprises a variable impedance.

12. The supply modulator of claim 11 , wherein the first inductor and the second inductor comprises fixed inductances, and
wherein the first capacitor and the second capacitor comprises variable capacitances.

13. The supply modulator of claim 1 , the first switched-mode power supplier further comprises an internal controller, the internal controller configured to select switching transistors used to generate the pulse signal, in response to a power control signal.

14. The supply modulator of claim 13 , wherein the amplitude of the pulse signal is controlled in response to the power control signal.

15. The supply modulator of claim 13 , wherein the switching circuit comprises a first transistor group and a second transistor group,
wherein switching transistors of the first transistor group have different size from switching transistors of the second transistor group,
wherein the internal controller is configured to select one of the first transistor group and the second transistor group in response to the power control signal, and
wherein the switching circuit is configured to transmit the pulse signal using the selected transistor group.

16. A supply modulator comprising:
a first switched-mode power supplier configured to transmit a modulated voltage to an output node in response to an envelope signal, the first switched-mode power supplier comprising:
a first sub switched-mode power supplier; and
a second sub switched-mode power supplier; and

a second switched-mode power supplier configured to selectively transmit a compensation current to the output node in response to a current transmitted from the first switched-mode power supplier,
wherein each of the first sub switched-mode power supplier and the second sub switched-mode power supplier comprise:
a switching circuit configured to transmit a pulse signal in response to an amplitude of the envelope signal; and
a low pass filter configured to generate the modulated voltage by filtering certain frequency band of the pulse signal, the low pass filter comprising a plurality of stages,

wherein each of the plurality of stages of the low pass filter comprises at least one variable impedances.

17. The supply modulator of claim 16 , wherein the each of the plurality of stages of the low pass filter comprises inductors having fixed inductances and capacitors having variable capacitances.

18. The supply modulator of claim 17 , wherein the first switched-mode power suppli

Assignees

• Samsung Electronics Co Ltd

Inventors

• Paek Ji Seon
• Kim Dongsu
• Choo Younghwan

Classifications

• H02M3/158 Primary

  including plural semiconductor devices as final control devices for a single load · CPC title

• H03F2200/102

  A non-specified detector of a signal envelope being used in an amplifying circuit · CPC title

• H03F1/0227 Primary

  using supply converters · CPC title

• H03F3/2173

  of the bridge type · CPC title

• H03F3/24

  of transmitter output stages · CPC title