Multipath Sampling Circuit for Wide Dynamic Range Without Saturation

Solution Overview

Problem

Conventional sampling circuits have limited dynamic range, leading to output saturation and increased noise when handling wide input signals, as they rely on linear input-to-output characteristics, which restricts their ability to accurately reproduce input voltages beyond a certain range without compromising noise performance.

Innovation Solution

A multipath sampling circuit with multiple voltage amplifiers and track-and-hold circuits, each with different gains and saturation voltages, allowing for a nonlinear input-output characteristic that extends the dynamic range without reducing noise performance by switching between different gain regions based on input voltage levels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Length of stationary object

If the gain of the sampling circuit is reduced to increase the input voltage range, then the saturation input voltage increases, but the noise level referred to the input increases proportionally

Engineering Contradiction:

Improveinput voltage rangeVSAvoidnoise level

Core Design Contradiction:

Length of stationary objectVSObject-affected harmful factors

Solution Approach 1:

The sampling circuit is divided into multiple parallel paths, each with a different gain factor (a1, a2, ..., an). Each path processes the input signal independently with its own track-and-hold circuit, allowing the system to handle a wider dynamic range without compromising noise performance by selecting or combining outputs from different gain paths.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The circuit uses multiple amplifiers with different fixed gain parameters (a1>V1>a2>...>an>Vn) to create multiple input ranges. By changing which path is active based on the input signal level, the system can maintain optimal noise performance across a wide dynamic range without requiring a single reduced gain setting.

Inventive Principle:

Principle #35Parameter changes

2Object-affected harmful factors

If a single gain setting is used in the sampling circuit, then the noise performance is maintained, but the input voltage range is limited by saturation

Engineering Contradiction:

Improvenoise performanceVSAvoidinput voltage range

Core Design Contradiction:

Object-affected harmful factorsVSLength of stationary object

Solution Approach 1:

The sampling circuit is divided into multiple parallel paths, each with a different gain factor (a1, a2, ..., an). Each path processes the input signal independently with its own track-and-hold circuit, allowing the system to handle a wider dynamic range without compromising noise performance by selecting or combining outputs from different gain paths.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The multipath sampling circuit serves multiple functions: it maintains low noise performance for small signals through high-gain paths while simultaneously handling large signals through low-gain paths. The circuit universally processes inputs across the entire dynamic range by having multiple gain configurations available in parallel.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Measurement precision

If the gain is increased to improve signal resolution, then the noise performance improves, but the input voltage range decreases due to earlier saturation

Engineering Contradiction:

Improvesignal resolutionVSAvoidinput voltage range

Core Design Contradiction:

Measurement precisionVSLength of stationary object

Solution Approach 1:

The sampling circuit is divided into multiple parallel paths, each with a different gain factor (a1, a2, ..., an). Each path processes the input signal independently with its own track-and-hold circuit, allowing the system to handle a wider dynamic range without compromising noise performance by selecting or combining outputs from different gain paths.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different paths are optimized for different signal levels: high-gain paths (a1) provide high resolution for small signals, while lower-gain paths (a2, ..., an) provide appropriate resolution for larger signals. Each path has its own track-and-hold circuit tailored to its specific gain characteristics, allowing local optimization for different input ranges.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS11533060B2Multipath sampling circuits

Publication Date: 2022.12.20 OMNI DESIGN TECH

AI summary

A multipath sampling circuit includes an input line electrically having an input voltage, a plurality of voltage amplifiers in parallel electrically with one another, each voltage amplifier having a respective input electrically coupled in series with the input line, each voltage amplifier having a different gain and a different saturation voltage; and a plurality of track-and-hold circuits. The track-and-hold circuits have a first state in which a respective input of each track-and-hold circuit is electrically coupled to an output of a respective amplifier. The track-and-hold circuits have a second state in which the respective input of each track-and-hold circuit is electrically decoupled from the output of the respective amplifier. The track-and-hold circuits can be electrically coupled to a summing circuit, a buffer amplifier, or an operational amplifier.