Multi-Band LNA Nested Inductor Layout for Smaller RF Receivers

Solution Overview

Problem

Conventional multi-band RF transceivers face challenges in miniaturization due to the large size and increased manufacturing costs of integrated inductors, which are necessary for impedance matching and low noise amplification across various frequency bands, leading to insufficient circuit area and high noise factors.

Innovation Solution

The design incorporates multiple low noise amplifying circuits with inductors arranged in loop patterns on the same layer, where one inductor surrounds others, allowing current to flow through a selected inductor, reducing circuit area and maintaining high impedance characteristics, and includes a multi-band RF receiver with SAW filters and down-mixing units to support multiple frequency bands.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional integrated inductors are used for impedance matching in multi-band RF transceivers, then impedance matching performance is improved, but circuit area increases and manufacturing cost increases

Engineering Contradiction:

Improveimpedance matching performanceVSAvoidcircuit area

Core Design Contradiction:

ReliabilityVSArea of stationary object

Solution Approach 1:

The patent implements nested inductor structures where smaller inductors are positioned inside larger inductors, allowing multiple inductors to share the same physical space. This nesting arrangement enables multiple frequency bands to be supported while significantly reducing the total circuit area occupied by inductors compared to conventional separate inductor layouts.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent combines multiple inductors into a single integrated structure where they share common physical space and potentially common fabrication processes. By merging the inductor structures and allowing them to overlap in the planar view, the design achieves multi-band functionality without proportionally increasing the total area.

Inventive Principle:

Principle #5Merging (Combining)

2Adaptability or versatility

If multiple inductors are included for N frequency bands, then multi-band operation is improved, but inductor circuit area increases

Engineering Contradiction:

Improvemulti-band operationVSAvoidinductor circuit area

Core Design Contradiction:

Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The patent implements nested inductor structures where smaller inductors are positioned inside larger inductors, allowing multiple inductors to share the same physical space. This nesting arrangement enables multiple frequency bands to be supported while significantly reducing the total circuit area occupied by inductors compared to conventional separate inductor layouts.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent designs inductor structures that can serve multiple frequency bands simultaneously or selectively. The nested inductors are configured such that each inductor can be activated for specific frequency bands, allowing a single integrated inductor structure to perform the function of multiple separate inductors across different bands.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Reliability

If inductor size is increased to maintain high impedance characteristics, then impedance performance is improved, but manufacturing cost increases

Engineering Contradiction:

Improveimpedance characteristicsVSAvoidmanufacturing cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent implements nested inductor structures where smaller inductors are positioned inside larger inductors, allowing multiple inductors to share the same physical space. This nesting arrangement enables multiple frequency bands to be supported while significantly reducing the total circuit area occupied by inductors compared to conventional separate inductor layouts.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent optimizes the geometric parameters of the nested inductor structures, such as trace width, spacing, and number of turns, to achieve high impedance characteristics without requiring large physical sizes. By carefully adjusting these parameters, the design maintains excellent impedance performance while minimizing the total area and reducing manufacturing costs.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS7877077B2Multi-band low noise amplifier and multi-band radio frequency receiver including the same

Publication Date: 2011.01.25 SAMSUNG ELECTRONICS CO LTD

AI summary

A multi-band low noise amplifier (LNA) includes multiple low noise amplifying circuits configured to selectively operate in corresponding frequency bands. The low noise amplifying circuits include corresponding amplifying units and degenerating units. The degenerating units include first inductors, which are arranged in loop patterns isolated from each other on a same layer, such that one first inductor surrounds at least one other first inductor. A current flows through a selected first inductor included in a selected low noise amplifying circuit of the low noise amplifying circuits.