Avalanche photodiode pixel
The present disclosure relates to an avalanche photodiode pixel including: a transistor adapted to be controlled by an enable signal having a first state for controlling the enabling of the pixel and a second state for controlling the disabling of the pixel, the transistor being configured to couple an avalanche photodiode of the pixel to a node of application of a substrate voltage when the enable signal is in the first state; and an output circuit adapted to be controlled by the enable signal and configured to provide a pixel output signal when the enable signal is in the first state and to block the pixel output signal when the enable signal is in the second state.
1 . A device, comprising:
a first pixel including:
an avalanche photodiode;
a detection circuit coupled to the avalanche photodiode, the detection circuit including a first inverter;
a transistor configured to be controlled by an enable signal having a first state for enabling the first pixel and a second state for disabling the first pixel, the transistor being configured to couple the avalanche photodiode to a node configured to apply a substrate voltage when the enable signal is in the first state; and
an output circuit configured to be controlled by the enable signal and configured to provide a pixel output signal when the enable signal is in the first state and to block the pixel output signal when the enable signal is in the second state, the output circuit including an output AND gate including a first input node that is coupled to an output node of the first inverter.
2 . The device according to claim 1 , wherein the enable signal is an enable voltage.
3 . The device according to claim 1 , wherein the detection circuit is configured to generate the pixel output signal.
4 . The device according to claim 3 , wherein the first inverter is configured to convert an analog signal generated by the avalanche photodiode into a digital signal to generate the pixel output signal.
5 . The device according to claim 1 , wherein the output AND gate in the output circuit includes a second input node configured to receive the enable signal, and an output node coupled to an output node of the first pixel.
6 . The device according to claim 5 , wherein the first input node of the output AND gate is configured to receive the pixel output signal.
7 . The device according to claim 6 , wherein the first inverter is powered by a dedicated power supply voltage.
8 . The device according to claim 4 , wherein the output circuit includes the first inverter, the first inverter being configured to be controlled by the enable signal applied to a power supply node of the first inverter.
9 . The device according to claim 8 , wherein the output node of the first inverter is coupled to an output node of the first pixel.
10 . The device according to claim 1 , wherein the output circuit is coupled to a counter configured to integrate the pixel output signal when the enable signal is in the first state.
11 . The device according to claim 4 , further comprising a second inverter between the first inverter and an output node of the detection circuit.
12 . The device according to claim 1 , further comprising a buffer configured to increase a power of the enable signal.
13 . The device of claim 1 , comprising a pixel matrix including a plurality of pixels substantially identical to the first pixel, wherein the pixel matrix includes the first pixel, wherein the pixels are organized into a plurality of sub areas each including a respective group of pixels coupled to a common counter.
14 . The device according to claim 13 , further comprising a selection circuit configured to selectively address the enable signal to a selected pixel of the pixels of a sub area, the selection circuit including an output node coupled at least to the transistor of the selected pixel.
15 . The device according to claim 14 , wherein the first input node of the output AND gate is configured to receive the pixel output signal, the output AND gate including a second input node configured to receive the enable signal, and an output node coupled to an output node of the pixel, wherein the output node of the selection circuit is also coupled to the second input node of the output AND gate.
16 . The device according to claim 14 , wherein each detection circuit is configured to generate the pixel output signal, the first inverter of the detection circuit configured to convert an analogic signal generated by the avalanche photodiode into a digital signal to generate the pixel output signal, wherein the output circuit includes the inverter, the inverter being configured to be controlled by the enable signal applied to a power supply node of the inverter, wherein the output node of the selection circuit is also coupled to the power supply node of the inverter.
17 . The device according to 14 , wherein each pixel includes a buffer configured to increase a power of the enable signal, wherein the buffer is included in the selection circuit.
18 . A method, comprising:
applying a substrate voltage to an avalanche photodiode of a pixel by enabling, with a first state of an enable signal, a transistor of the pixel;
disabling, with a second state of the enable signal, the transistor;
controlling an output circuit of the pixel with the enable signal;
generating a pixel output signal with a detection circuit of the pixel, the detection circuit including a first inverter and a second inverter coupled between the first inverter an output node of the detection circuit;
providing, with the output circuit, the pixel output signal when the enable signal is in the first state; and
blocking the pixel output signal when the enable signal is in the second state.
19 . The method of claim 18 , wherein the detection circuit is coupled to the avalanche photodiode.
20 . The method of claim 18 , comprising:
receiving, with a first input node of an AND gate of the output circuit, the pixel output signal;
receiving, with a second input node of the AND gate, the enable signal; and
providing the pixel output signal with an output node of the AND gate.
21 . A device, comprising:
a selection circuit configured to output an enable signal;
a pixel coupled to the selection circuit and including:
an avalanche photodiode;
a detection circuit coupled to the avalanche photodiode, the detection circuit including a first inverter;
a transistor coupled between the avalanche photodiode and a substrate voltage and having a gate terminal configured to receive the enable signal;
an output circuit having a first input coupled to the avalanche photodiode, a second input coupled to receive the enable signal, and an output, the output circuit including an output AND gate including a first input node that is coupled to an output node of the first inverter.
22 . The device of claim 21 , wherein the output circuit includes a high supply terminal corresponding to the second input of the output circuit, and an output correspond to the output of the output circuit.
23 . The device of claim 21 , wherein the AND gate in the output circuit includes a second input node configured to receive the enable signal.