Split Current IDAC for RF PA Stage Dynamic Biasing

Solution Overview

Problem

Traditional multi-mode multi-band RF communications devices require complex and costly circuitry to support various communication modes and frequency bands, leading to size, cost, and power consumption issues in portable devices.

Innovation Solution

A split current IDAC and RF power amplifier (PA) stage that operates in selected DDS modes, providing array bias signals to amplify RF signals using groups of transistor elements, allowing for efficient and flexible operation across multiple modes and bands.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If traditional multi-mode multi-band RF circuitry is used to support various communication modes and frequency bands, then adaptability is improved, but device complexity and cost increase

Engineering Contradiction:

Improvemulti-mode multi-band supportVSAvoidcircuitry complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent implements a universal RF power amplifier stage that can operate across multiple communication modes (full-duplex, half-duplex, TDD, FDD) and frequency bands by using a single set of amplifier circuits with reconfigurable biasing. The split-current IDAC provides different bias current distributions to the same amplifier devices, enabling them to adapt to different operational requirements without requiring separate dedicated circuits for each mode or band.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent employs dynamic reconfiguration of the RF power amplifier stage through a split-current IDAC that can dynamically adjust bias current distribution among amplifier devices. This dynamic biasing control allows the same hardware to adapt its characteristics in real-time based on the selected communication mode and frequency band, transitioning from static dedicated circuits to dynamically reconfigurable architecture.

Inventive Principle:

Principle #15Dynamics

2Adaptability or versatility

If traditional multi-mode multi-band RF circuitry is used to support various communication modes and frequency bands, then adaptability is improved, but size and power consumption increase

Engineering Contradiction:

Improvemulti-mode multi-band supportVSAvoidpower consumption

Core Design Contradiction:

Adaptability or versatilityVSUse of energy by moving object

Solution Approach 1:

The patent implements a universal RF power amplifier stage that can operate across multiple communication modes (full-duplex, half-duplex, TDD, FDD) and frequency bands by using a single set of amplifier circuits with reconfigurable biasing. The split-current IDAC provides different bias current distributions to the same amplifier devices, enabling them to adapt to different operational requirements without requiring separate dedicated circuits for each mode or band.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent changes the operational parameters of the RF power amplifier by dynamically adjusting bias currents through the split-current IDAC. By varying the bias current distribution among amplifier devices based on the selected mode and band, the system optimizes power consumption for each operational scenario while maintaining adaptability across multiple modes and frequency bands.

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If traditional multi-mode multi-band RF circuitry is used to support various communication modes and frequency bands, then adaptability is improved, but cost increases

Engineering Contradiction:

Improvemulti-mode multi-band supportVSAvoidmanufacturing cost

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The patent implements a universal RF power amplifier stage that can operate across multiple communication modes (full-duplex, half-duplex, TDD, FDD) and frequency bands by using a single set of amplifier circuits with reconfigurable biasing. The split-current IDAC provides different bias current distributions to the same amplifier devices, enabling them to adapt to different operational requirements without requiring separate dedicated circuits for each mode or band.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent merges multiple previously separate RF amplifier circuits into a single reconfigurable amplifier stage. By combining full-duplex and half-duplex/TDD amplifier circuits into one unified structure with dynamic biasing control, the invention reduces the total component count and manufacturing complexity while maintaining support for all communication modes and frequency bands.

Inventive Principle:

Principle #5Merging (Combining)

Data Source

PatentUS8565694B2Split current current digital-to-analog converter (IDAC) for dynamic device switching (DDS) of an RF PA stage

Publication Date: 2013.10.22 QORVO US INC

AI summary

A split current current digital-to-analog converter (IDAC) and a radio frequency (RF) power amplifier (PA) stage are disclosed. The split current IDAC operates in a selected one of a group of DDS operating modes and provides a group of array bias signals based on the selected one of the group of DDS operating modes. Each of the group of array bias signals is a current signal. The RF PA stage includes a group of arrays of amplifying transistor elements. The RF PA stage biases at least one of the group of arrays of amplifying transistor elements based on the group of array bias signals. Further, the RF PA stage receives and amplifies an RF stage input signal to provide an RF stage output signal using at least one of the group of arrays of amplifying transistor elements that is biased.