Optical Receiver Integrator Circuit to Suppress Output Inversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In optical reception devices, large negative offset voltages can cause inversion of integrator outputs, leading to delayed transient responses and failure in normal signal reception due to increased potential differences.
Innovation Solution
An optical reception device with an inversion suppression circuit that injects current into the positive phase and extracts current from the negative phase when the negative phase potential is higher, using an operational transconductance amplifier and current mirror circuits to manage potential differences and suppress output inversion.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a large negative offset voltage is applied to the reference voltage to stop the releasing function, then the releasing function is stopped, but the output of the integrator inverts and transient response is delayed
Solution Approach 1:
The inversion suppression circuit applies a counteracting current in advance to prevent the harmful effect of output inversion. When the negative offset voltage causes the integrator output to invert, the inversion suppression circuit detects this condition and applies a compensating current to the positive phase or extracts current from the negative phase, thereby preventing the inversion from affecting the transient response of the releasing function.
Solution Approach 2:
The inversion suppression circuit acts as an intermediary between the integrator and the releasing function control. It monitors the integrator output and intervenes when inversion occurs, using current injection or extraction to maintain proper potential relationships without directly altering the reference voltage or offset voltage settings.
2Ease of operation
If a negative offset voltage is applied to produce a voltage lower than the output of the amplification stage, then the releasing function stopping is achieved, but the potential difference increases causing output inversion
Solution Approach 1:
The invention converts the harmful effect of increased potential difference into a beneficial control mechanism. The inversion suppression circuit uses the potential difference created by the negative offset voltage as a signal to trigger current injection or extraction, thereby transforming the harmful inversion effect into a controllable condition that can be corrected without changing the original offset voltage settings.
Solution Approach 2:
The inversion suppression circuit dynamically changes the current parameters in the feedback path based on the integrator output state. When inversion is detected, the circuit adjusts the current magnitude and direction by injecting current to the positive phase or extracting current from the negative phase, thereby restoring proper potential relationships without altering the reference voltage parameter.
Data Source
AI summary
An optical reception device includes: a light receiving element; an amplifier which receives and amplifies a current based on an input current from the light receiving element; a direct-current adjustment circuit which removes an offset current included in the input current; an alternating-current adjustment circuit which causes a part of the input current to flow therein; and a controller which controls the direct-current adjustment circuit and the alternating-current adjustment circuit. The controller includes an integrator configured to integrate an output of the amplifier and output a resultant output to two electric paths of a positive phase and a negative phase, and an inversion suppression circuit configured to operate so as to inject a current to the positive phase and extract a current from the negative phase when a negative phase potential of an output of the integrator is higher than a positive phase potential thereof.