Multi-data rate, burst-mode transimpedance amplifier (TIA) circuit
AssigneeAvago Technologies General IP (Singapore) Pte. Ltd.
InventorsRahul Shringarpure, Georgios Asmanis, Faouzi Chaahoub, Kartikeya Gupta
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Abstract
A burst-mode TIA circuit for use in PON receivers is provided that supports multiple data rates, has high receiver sensitivity, wide dynamic range, and that performs burst-mode synchronization very quickly. The multi-rate burst-mode TIA circuit has a high-speed data path that has low input-referred noise. Based on the chosen data rate at which the multi-rate burst-mode TIA circuit will operate, the rate select switch selects an appropriate feedback resistor of the resistive feedback network.
Claims19
A transimpedance amplifier (TIA) circuit for use in a receiver used to receive asynchronous data sent in bursts over optical networks, the TIA circuit being capable of operating at multiple data rates, the TIA circuit receiving an TIA input signal at an input terminal of the TIA circuit and outputting a TIA output signal from an output terminal of the TIA circuit;
- a data rate selection circuit that is configured to be switched between multiple settings to select the data rate at which the TIA circuit operates;
- a direct current (DC) offset correction loop configured to apply a DC offset correction at the input terminal of the TIA circuit, wherein the DC offset correction loop comprises:
- a capacitor bank comprising a plurality of capacitors and at least a first switch that can be activated and deactivated;
- a direct current (DC) injecting/bleeding circuit electrically coupled to the input terminal of the TIA circuit and to the capacitor bank and comprising at least a second switch that can be activated and deactivated and at least a first bleed transistor;
- and
- a level detection circuit that selectively activates and deactivates the first and second switches based on a TIA output signal outputted from the output terminal to control said at least a first bleed transistor to inject current into or shunt current away from the input terminal.
A transimpedance amplifier (TIA) circuit for use in a receiver used to receive asynchronous data sent in bursts over optical networks, the TIA circuit having an input terminal that receives a TIA input signal and an output terminal that outputs a TIA output signal, the TIA circuit comprising:
- an automatic gain control (AGC) loop configured to automatically control a gain of the TIA circuit, wherein the AGC loop includes a level detection circuit having an input that is electrically coupled to the output terminal of the TIA circuit, the level detection circuit detecting a peak-to-peak amplitude of the TIA output signal;
- M comparators that are triggered when an output signal of the TIA circuit crosses M threshold levels, respectively, where M is a positive integer that is greater than or equal to 2, the M comparators outputting M signals representing M bit, respectively, such that an M-bit current signal is output by the level detection circuit;
- an M-bit current-mode digital-to-analog converter (DAC) that converts the M bits into an analog current signal and output the analog current signal;
- and
- a current-to-voltage converter that converts the analog current signal outputted from the M-bit DAC into an analog voltage signal and outputs the analog voltage signal, and wherein the level detection circuit causes the gain of the TIA circuit to be adjusted based on the analog voltage signal outputted from the current-to-voltage converter.
Dependencies are inferred from the claim text.