Controller IC Input/Output Node Multiplexing for Pin Reduction

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Controller IC devices for switched mode power converters face limitations due to the limited number of input/output nodes, which restricts their functionality and compatibility with stringent encapsulation requirements.

Innovation Solution

A controller IC device with an input/output unit configured to receive and output current through the same node, utilizing a current mirror unit and a transistor to measure and regulate output voltage, allowing for voltage regulation control and reduced node requirements.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If different input/output nodes are used for different purposes, then the functionality of the controller IC is improved, but the number of input/output nodes increases, which conflicts with encapsulation requirements

Engineering Contradiction:
ImprovefunctionalityVSAvoidnumber of input/output nodes
Core Design Contradiction:
Adaptability or versatilityVSQuantity of substance

Solution Approach 1:

The patent implements multi-functionality by enabling a single input/output node to serve multiple purposes: receiving feedback current from the optocoupler, outputting voltage regulation status, and providing voltage regulation control. This is achieved through circuitry that allows the node to handle different signal types sequentially or simultaneously, thereby maintaining full controller functionality while reducing the total pin count to meet stringent encapsulation requirements

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Ease of manufacture

If the number of input/output nodes is reduced to meet encapsulation requirements, then the encapsulation compliance is improved, but the functionality and versatility of the controller IC deteriorates

Engineering Contradiction:
Improveencapsulation complianceVSAvoidfunctionality
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent merges multiple functions into a single input/output node by combining the feedback current reception, voltage regulation status output, and control signal provision into one unified interface. This consolidation reduces the number of required pins while maintaining all necessary controller IC functionalities, ensuring compliance with stringent encapsulation requirements without sacrificing adaptability

Inventive Principle:
Principle #5Merging (Combining)

3Quantity of substance

If the same input/output node is used for both receiving input current and outputting output voltage, then the number of input/output nodes is reduced, but the signal interference and measurement precision may deteriorate

Engineering Contradiction:
Improvenumber of input/output nodesVSAvoidvoltage regulation status indication accuracy
Core Design Contradiction:
Quantity of substanceVSMeasurement precision

Solution Approach 1:

The patent employs periodic action by alternating between current reception mode and voltage output mode for the same input/output node. The node receives feedback current during specific time periods when the switching regulator is not actively driving the optocoupler, and outputs voltage regulation status during other periods. This time-division multiplexing prevents signal interference while maintaining measurement precision for voltage regulation status indication

Inventive Principle:
Principle #19Periodic action

Data Source

PatentEP3404812B1Controller IC device for a switched mode power converter and method for operating a controller IC device of a switched mode power converter
Publication Date: 2020.11.11 NXP BV
  • EP3404812B1 patent drawingFigure 1
  • EP3404812B1 patent drawingFigure 2
  • EP3404812B1 patent drawingFigure 3

AI summary

Embodiments of a controller integrated circuit (IC) device for a switched mode power converter and a method of operating a controller IC device of a switched mode power converter are described. In one embodiment, a controller IC device for a switched mode power converter an input/output unit connected to an input/output node of the controller IC device and a controller unit. The input/output unit is configured to receive an input current from the input/output node and output an output voltage through the input/output node in response to an input voltage received at the input/output unit. The controller unit is configured to control voltage regulation of the switched mode power converter in response to the input current received from the input/output unit and generate the input voltage for the input/output unit. Other embodiments are also described.