Low noise and low input capacitance differential MDS LNA

一种放大器、差动输入的技术,应用在带有半导体器件/放电管的放大器、放大器、改进放大器以减少非线性失真等方向,能够解决不合意大的输入电容等问题

Active Publication Date: 2010-12-01
QUALCOMM INC
View PDF2 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Furthermore, the gate of the cancellation FET 16 is coupled to the input lead 20 of the LNA 15, causing the LNA 15 to have an undesirably large input capacitance

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Low noise and low input capacitance differential MDS LNA
  • Low noise and low input capacitance differential MDS LNA
  • Low noise and low input capacitance differential MDS LNA

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0040] Figure 4 is a very simplified high level block diagram of one particular type of mobile communication device 100 in accordance with one novel aspect. In this example, the mobile communication device 100 is a 3D cellular phone using the CDMA2000 cellular phone communication protocol. The cellular telephone includes (among several other components not illustrated) an antenna 102 and two integrated circuits 103 and 104 . The integrated circuit 104 is called a "digital baseband integrated circuit" or a "baseband processor integrated circuit". Integrated circuit 103 is an RF transceiver integrated circuit. The RF transceiver integrated circuit 103 is referred to as a "transceiver" because it includes a transmitter as well as a receiver.

[0041] Figure 5 yes figure 1 A more detailed block diagram of the RF transceiver integrated circuit 103. The receiver includes what is called a “receive chain” 105 and a local oscillator (LO) 106 . A high frequency RF signal 107 is...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A differential low noise amplifier (LNA) involves two main amplifying transistors biased in saturation, and two cancel transistors biased in sub-threshold. In one example, the gates of the cancel transistors are coupled to the drains of main transistors, in a symmetrical and cross-coupled fashion. The main transistors are source degenerated. Because the gates of cancel transistors are not coupled to the differential input leads of the LNA, the input capacitance of the LNA is reduced. Noise introduced into the LNA output due to the cancel transistors being biased in the sub-threshold region is reduced because there are two stages. The first stage involves the main transistors, and the second stage involves the cancel transistors. By increasing the gain of the first stage and decreasing the gain of the second stage, overall LNA gain is maintained while reducing the noise that the sub-threshold biased transistors contribute to the LNA output.

Description

technical field [0001] The disclosed embodiments relate to low noise amplifiers. Background technique [0002] The first amplification stage in a radio receiver, such as that of a cellular telephone, is typically an amplifier circuit called a low noise amplifier (LNA). The LNA reduces the noise contribution of the following stages and sets the lowest achievable noise level for the overall receiver. LNAs are therefore typically designed with high gain to minimize the amount of noise introduced without introducing an unacceptably large amount of distortion. If a sinusoidal input signal with a purely single frequency is supplied to the input of a linear amplifier, the amplifier will output an amplified version of the input signal. The output signal will only have a single frequency, and this frequency will be the frequency of the input signal. However, if the same sinusoidal input signal is supplied to the input of an amplifier exhibiting a certain amount of nonlinearity, th...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): H03F1/32
CPCH03F2203/45318H03F1/3205H03F1/3211H03F2203/45396H03F3/45188
Inventor 乔斯·卡瓦尼利亚斯普拉萨德·S·古德曼金那苏克里斯蒂安·马尔库阿努普·萨芙拉
Owner QUALCOMM INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products