Trigger Circuit Transient Immunity via State-Dependent Capacitance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Integrated circuits face challenges in transient voltage suppression, particularly for both unpowered and powered transient events, as existing solutions often fail to effectively manage voltage fluctuations, leading to potential damage or destruction.
Innovation Solution
A trigger circuit is designed to detect transient voltage increases and control a clamping device, utilizing a common capacitive element with different time values for unpowered and powered states, allowing for variable timing responses to manage voltage excursions effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single time value is used for transient voltage suppression, then the circuit design is simplified, but the transient immunity for both unpowered and powered states cannot be effectively improved
Solution Approach 1:
A single common capacitive element is used to provide multiple time values (first time value for unpowered state, second time value for powered state) by switching between different configurational states. This multi-functional approach allows one component to serve multiple timing purposes, improving transient immunity for both states without proportionally increasing device complexity
Solution Approach 2:
The capacitive element's configurational state is dynamically switched between first and second states based on the operational state (powered or unpowered). This dynamic reconfiguration allows the circuit to adapt the timing characteristics to the current operational context, optimizing transient suppression for each state while using the same physical component
2Measurement precision
If different capacitive elements are used for unpowered and powered states, then the timing precision for each state is improved, but the device complexity and component count increase
Solution Approach 1:
One common capacitive element performs the timing function for both unpowered and powered states by being switched between different configurational states. This eliminates the need for separate capacitive elements while maintaining the ability to provide state-appropriate timing precision through the single multi-functional component
3Reliability
If a remote voltage reference circuit is used, then the voltage reference stability is improved, but the device complexity and area increase
Solution Approach 1:
The voltage reference function is extracted from a separate remote circuit and integrated into the trigger circuit itself. The common capacitive element and switching mechanism provide the necessary timing and reference functions locally, eliminating the need for a remote voltage reference circuit while maintaining the required stability through the state-dependent timing configuration
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 enhances transient immunity by distinguishing between unpowered and powered states, providing appropriate timing responses to prevent voltage rail collapse and reduce the need for a remote voltage reference circuit, thereby improving ESD clamp response and reducing false triggering.
Implementation Method 1
a common capacitive element having a capacitive value, wherein a first time value and a second time value are dependent upon the capacitive value of the common capacitive element
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A trigger circuit (106) detects a transient voltage increase (502, 607) on an integrated circuit. The trigger circuit (106) controls a conductivity state of a clamping device (112) to limit the transient voltage increase (507, 609). The trigger circuit (106) comprises a common capacitive element (107, 205) having a capacitive value, wherein a first time value and a second time value are dependent upon the capacitive value of the common capacitive element (107, 205), the first time value applicable to an unpowered state of the integrated circuit (461) and the second time value applicable to a powered state of the integrated circuit (462) (603). The first time value and the second time value control a trigger circuit parameter which may include a detection range within which a rate of transient voltage increase causes the trigger circuit (106) to become active (454, 455) or an "on" time upon which an active duration of control of the conductivity state of the clamping device (112) depends (456, 457).