Bias Voltage Calibration Circuit for Accurate Equalizer Current
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional signal receiving devices face errors due to process variations and temperature changes, which affect the accuracy of bias current generation, often requiring large bandgap reference voltage circuits and external resistors that occupy space and introduce noise.
Innovation Solution
A bias voltage calibration circuit comprising a reference voltage generator, voltage-current converter, and bias current generator, which adjusts the reference voltage and current to provide accurate bias currents to the equalization circuit, eliminating the need for external resistors and reducing errors from process and temperature variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a bandgap reference voltage generating circuit is used to provide reference voltage, then the bias current can be generated, but the circuit size becomes large and error remains due to process variation and temperature change
Solution Approach 1:
The patent changes the parameters of the reference voltage by introducing a voltage adjustment signal that can modify the reference voltage value. This allows the bias current to be adjusted to compensate for process variation and temperature change, improving reliability without requiring a larger circuit. The voltage adjustment signal enables dynamic parameter tuning to maintain accuracy under varying conditions.
2Reliability
If an external resistor is used to generate bias current, then the bias current can be provided, but the external resistor occupies circuit area and provides a path for external noise coupling
Solution Approach 1:
The patent extracts and eliminates the external resistor from the circuit by generating the bias current internally using the adjusted reference voltage and current mirror circuits. This removes the harmful external noise coupling path while maintaining the ability to provide accurate bias current to the equalization circuit, thereby improving signal accuracy without external components.
3Reliability
If conventional bias current generation is used, then the circuit is simple, but the bias current has error due to process variation and temperature change
Solution Approach 1:
The patent implements a feedback mechanism where the voltage adjustment signal is used to modify the reference voltage based on the required bias current accuracy. This feedback approach compensates for process variation and temperature change effects, maintaining bias current stability and accuracy without complex circuitry. The system continuously adjusts the reference voltage to counteract environmental variations.
Data Source
AI summary
The disclosure provides a bias voltage calibration circuit adapted for a signal receiving device. The bias voltage calibration circuit includes a reference voltage generator, a voltage-current converter, and a bias current generator. The reference voltage generator receives a voltage adjustment signal, and adjusts a voltage value of a generated reference voltage according to the voltage adjustment signal. The voltage-current converter is coupled to the reference voltage generator, and converts the reference voltage to generate a reference current. The bias current generator generates a plurality of bias currents according to the reference current, and provides the bias current to an equalization circuit of the signal receiving device in a calibration mode.