Envelope Tracker PMIC State Mapping for Rapid PA Mode Transitions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing envelope tracking systems face limitations in transitioning between operational modes due to slow transition times, particularly in applications like Wi-Fi, where rapid mode changes are necessary to adapt to varying transmit power requirements.
Innovation Solution
A tracker circuit with a predefined state machine circuit that uses a digital selection signal to manage transitions between operational modes, employing a mapping scheme that includes allowable and forbidden state transitions to facilitate faster mode changes, thereby enabling efficient power amplifier operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If conventional envelope tracking systems are used, then power amplifier efficiency is improved, but transition time between operational modes is slow
Solution Approach 1:
The patent segments the operational modes into distinct states within a state machine circuit, where each state represents a specific operational mode with predefined voltage levels. This segmentation allows for discrete, rapid transitions between modes by simply changing the state machine's current state, rather than continuously adjusting parameters, thereby reducing transition time while maintaining power amplifier efficiency.
Solution Approach 2:
The patent implements preliminary action by pre-defining the mapping between states and operational modes in the state machine circuit before operation begins. The mapping scheme, including allowable and forbidden transitions, is established in advance, enabling the system to immediately execute valid mode transitions without calculation or decision delays, thus achieving fast response for applications like Wi-Fi.
2Adaptability or versatility
If rapid mode transitions are implemented, then adaptability is improved, but system complexity increases
Solution Approach 1:
The state machine circuit serves multiple functions simultaneously: it tracks the envelope of the RF signal, manages transitions between operational modes, and controls the voltage levels supplied to the power amplifier. By consolidating these functions into a single universal circuit block with a predefined state mapping, the patent achieves rapid adaptability without proportionally increasing overall system complexity.
Solution Approach 2:
The patent changes the control parameter from continuous analog voltage adjustment to discrete digital state transitions. The tracker circuit uses a digital state machine where each state corresponds to a specific operational mode and voltage level. This parameter change enables rapid adaptation to varying transmit power requirements through simple state transitions, while the predefined mapping scheme keeps the control logic manageable and avoids excessive complexity.
Data Source
AI summary
A tracker circuit configured to provide a variable supply voltage to a power amplifier (PA) circuit is disclosed. The tracker circuit includes a state machine circuit comprising a plurality of states mapped in accordance with transitions associated with a mapping scheme. In some embodiments, the plurality of states of the state machine circuit identify one or more operational modes associated with the tracker circuit, wherein at least one operational mode comprises one or more voltage levels respectively associated therewith. In some embodiments, the one or more operational modes includes at least two active operational modes. In some embodiments, a transition between the one or more operational modes of the tracker circuit is controlled by a digital selection signal received from a digital communication interface associated therewith.