IC Pre-Charging Circuit Replica Current Control

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional pre-charging devices for integrated circuits fail to accurately replicate the current drain in secondary supply mode, leading to transient voltage drops or overvoltages during mode transitions, which can result in data loss or component stress.

Innovation Solution

A pre-charging circuit with a replica circuit and current-amplifying circuit that generates a pre-charging current representative of the current passed by the memory circuit in secondary supply mode, ensuring accurate voltage regulation and minimizing power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional pre-charging devices (resistor or transistor-based circuit) are used, then the secondary supply can be pre-charged, but the pre-charging current cannot accurately match the current drain, causing transient voltage drops or overvoltages

Engineering Contradiction:

Improvedata retention reliabilityVSAvoidtransient voltage drop or overvoltage

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent uses a replica circuit that copies the exact structure and characteristics of the memory circuit to be protected. This replica circuit generates a pre-charging current that accurately matches the current drain of the actual memory circuit, eliminating transient voltage drops or overvoltages during mode transitions. The copying principle ensures that the pre-charging current is precisely tailored to the specific circuit being protected.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent dynamically adjusts the pre-charging current parameters based on the actual current drain characteristics of the memory circuit. By changing the current parameters to match the specific operational characteristics of the memory circuit, the system achieves accurate pre-charging without causing voltage transients, thereby protecting data retention reliability.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If pre-charging current is increased to prevent voltage drops, then data retention is improved, but transient overvoltage occurs causing component stress

Engineering Contradiction:

Improvedata retentionVSAvoidcomponent stress resistance

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent employs a feedback mechanism where the replica circuit continuously monitors and replicates the current drain characteristics of the memory circuit. This feedback loop ensures that the pre-charging current is precisely matched to the actual current requirements, preventing both voltage drops and overvoltages. The feedback principle allows the system to automatically adjust the pre-charging current to the optimal level without manual intervention.

Inventive Principle:

Principle #23Feedback

3Use of energy by moving object

If secondary supply voltage is reduced to minimize power consumption, then power efficiency is improved, but voltage stability during mode transition deteriorates

Engineering Contradiction:

Improvepower consumptionVSAvoidvoltage stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent applies preliminary action by pre-charging the secondary supply voltage before the mode transition occurs. The replica circuit generates the appropriate pre-charging current in advance, preparing the secondary supply to immediately assume the full current drain load when switching occurs. This preliminary action ensures voltage stability during transition while allowing the secondary supply voltage to be reduced for power savings during normal operation.

Inventive Principle:

Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution effectively limits or eliminates transient voltage drops and overvoltages, allowing the secondary supply voltage to be reduced to a minimum value for data retention while optimizing power consumption in secondary supply mode.

Implementation Method 1

a replica circuit that has the same configuration as at least one portion of the memory circuit and that is intended to pass a replica current

Methodology Applied

Scientific EffectCurrent replication: Conduction (electrical)

Implementation Method 2

to generate, in the primary supply mode, from the replica current, a pre-charging current that is representative of a current passed by the memory circuit in the secondary supply mode

Methodology Applied

Scientific EffectElectrical conduction: Conduction (electrical)

Data Source

PatentUS11670956B2Method for precharging an integrated-circuit supply, and corresponding integrated circuit

Publication Date: 2023.06.06 STMICROELECTRONICS (ROUSSET) SAS

AI summary

An integrated circuit includes: a primary supply stage including a primary supply node, the primary supply stage being configured to deliver a primary supply voltage to the primary supply node; a secondary supply stage including a secondary supply node, the secondary supply stage being configured to deliver a secondary supply voltage to the secondary supply node; a supply-switching circuit; a pre-charging circuit controllably coupled to the secondary supply node via the supply-switching circuit; and a volatile memory circuit controllably coupled to the primary supply node and the secondary supply node via the supply-switching circuit, wherein the switching circuit is configured to connect a supply of the volatile memory circuit either to the primary supply node in a primary supply mode, or to the secondary supply node in a secondary supply mode.