On-Chip Voltage Measurement Using Comparator and Storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for voltage measurement in integrated circuits face challenges such as high cost, resource consumption, and limited temporal resolution, particularly in measuring supply voltage and clock signal properties within the chip, due to parasitic effects and noise introduced by off-chip measurement techniques.
Innovation Solution
A system comprising an on-chip comparator and storage device that compares a test voltage to a reference voltage, with off-chip equipment generating the reference voltage and probe signals to retrieve the storage state, allowing for efficient high-speed voltage measurements with minimal chip resource usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional off-chip voltage measurement is used, then voltage can be measured using external equipment, but parasitic effects from package and I/O ports degrade measurement accuracy
Solution Approach 1:
The harmful I/O ports and package are extracted from the measurement path. The voltage is measured entirely on-chip using a comparator and storage device, eliminating the need to take the signal through I/O ports to external equipment, thus removing parasitic effects from the measurement path
Solution Approach 2:
An on-chip storage device acts as an intermediary between the voltage signal and external probing equipment. The storage device captures the voltage state and holds it for later reading, allowing the actual measurement to occur on-chip while external equipment only reads the stored result without introducing parasitics
2Measurement precision
If on-chip A/D converters are implemented, then measurement accuracy improves, but chip area and system complexity increase significantly
Solution Approach 1:
Instead of implementing expensive, complex permanent A/D converter logic on-chip, the invention uses a simple, inexpensive comparator and storage device that can be easily fabricated. The measurement is performed by capturing the voltage state in the storage device, which is then read externally, avoiding the need for complex on-chip conversion logic
Solution Approach 2:
The complex electronic A/D conversion process is replaced with a simpler voltage comparison and storage mechanism. The comparator performs a binary comparison of the voltage against a reference, and the result is stored in a simple storage device, replacing the need for complex analog-to-digital conversion circuitry
3Ease of operation
If sense lines are physically attached to pin assignments, then voltage can be taken off-chip for measurement, but the number of free I/O ports is reduced
Solution Approach 1:
The on-chip storage device serves multiple functions: it stores voltage measurement data, acts as a buffer between on-chip and off-chip systems, and enables reading by external equipment. This multi-functionality eliminates the need for dedicated sense lines, as the same I/O ports can be used for both normal operation and measurement purposes
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
Enables accurate and efficient detection of voltage drops and rises, as well as temporal variations of voltage waveforms within the chip, with reduced noise and parasitic effects, while minimizing chip area and I/O port usage.
Implementation Method 1
an on-chip comparator configured for comparing said test voltage level to a reference voltage level
Data Source
AI summary
A system for measuring a test voltage level (Vx) in a location within a chip is presented. The system includes an on-chip measurement device with an on-chip comparator and an on-chip storage. The on-chip comparator is configured for comparing the test voltage (Vx) to be measured to a reference voltage (Vref), while the on-chip storage is configured for storing the result of this comparison. The system also includes external (off-chip) equipment for generating the reference voltage (Vref), for generating probe signals for probing the state of the storage and for retrieving the state of said on-chip storage.