# US 9,520,426 B2 · Vision sensor chip with open-loop amplifier, operating method, and data processing system including same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,520,426 B2 - Document ID: US9520426B2 - Status: Granted - Kind: B2 - Application number: 14/578,639 - Filed: 2014-12-22 - Published: 2015-07-09 - Granted: 2016-12-13 - Earliest claimed: 2014-01-08 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Moo Young Kim; Yun Hong Kim; Seok Yong Hong; Tae Chan Kim; Jae Cheol Yun - Inventors: Moo Young Kim; Yun Hong Kim; Seok Yong Hong; Tae Chan Kim; Jae Cheol Yun - Web page: https://patentgrep.com/patent/US9520426B2 ## CPC - H10F 39/8037: {the integrated elements comprising a transistor} - H04N 25/00: Circuitry of solid-state image sensors [SSIS]; Control thereof - H04N 25/47: Image sensors with pixel address output; Event-driven image sensors; Selection of pixels to be read out based on image data - H10F 39/811: {Interconnections} - H10F 39/812: {Arrangements for transferring the charges in the image sensor perpendicular to the imaging plane, e.g. buried regions used to transfer generated charges to circuitry under the photosensitive region} - H10F: INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract A vision sensor chip includes a photoelectric conversion element that generates a current based on an incident light, a current-voltage (I-V) converter that converts the current into a voltage, an AC coupling capacitor directly connected to the I-V converter, an open-loop amplifier that includes a reset switch and amplifies a voltage provided by the I-V converter via the AC coupling capacitor. An event detection block detects motion according to a change in the amplified output voltage and generates first and second detection signals. A reset signal generator generates a reset signal controlling operation of the reset switch in response to first and second control signals respectively related to the first and second detection signals. ## Claims ### Claim 1 A vision sensor chip comprising: a photoelectric conversion element that generates a current in response to incident light; a current-voltage converter that converts the current into a corresponding voltage and provides the corresponding voltage at an output terminal; an AC coupling capacitor directly connected to the output terminal of the current-voltage converter that receives the corresponding voltage and generates an output voltage; an open-loop amplifier including a reset switch that amplifies the output voltage to generate an amplified output voltage; an event detection block that detects motion in relation to a change in the amplified output voltage and generates first and second detection signals; and a reset signal generator that generates a reset signal controlling operation of the reset switch in response to first and second control signals respectively related to the first and second detection signals. ### Claim 2 (depends on 1) The vision sensor chip of claim 1, wherein the current-voltage converter comprises: a bias circuit connected between a first line supplying an operating voltage and the output terminal of the current-voltage converter; a first transistor connected between the output terminal of the current-voltage converter and ground and including a gate connected to the photoelectric conversion element; and a second transistor connected between a second line and the photoelectric conversion element and including a gate connected to the output terminal of the current-voltage converter. ### Claim 3 (depends on 1) The vision sensor chip of claim 1, wherein the first and second detection signals have the same phase. ### Claim 4 (depends on 3) The vision sensor chip of claim 3, wherein the first and second control signals have opposite phases. ### Claim 5 (depends on 1) The vision sensor chip of claim 1, wherein the event detection block comprises: a switch signal generation circuit that generates an ON switch signal and an OFF switch signal respectively based on comparison results between the amplified output voltage and a first threshold voltage and a second threshold voltage having a different level that the first threshold voltage; and an event detection circuit that generates the first and second detection signals in response to one of the first and second control signals, the reset signal, the ON switch signal and the OFF switch signal. ### Claim 6 (depends on 5) The vision sensor chip of claim 5, wherein the switch signal generation circuit comprises: a ON switch signal generator that compares the amplified output voltage with the first threshold voltage and outputs the ON switch signal; and an OFF switch signal generator that compares the amplified output voltage with the second threshold voltage and outputs the ON switch signal. ### Claim 7 (depends on 1) The vision sensor chip of claim 1, wherein the reset signal generator comprises: a capacitor; a discharge circuit connected in parallel with the capacitor; and a switch circuit that in response to one of the first and second control signals supplies the other of the first and second control signals to the capacitor. ### Claim 8 A data processing system comprising: a vision sensor chip including vision sensor pixels and a processor controlling operation of the vision sensor chip, wherein each vision sensor pixel comprises: a photoelectric conversion element that generates a current in response to incident light; a current-voltage converter that converts the current into a corresponding voltage and provides the corresponding voltage at an output terminal; an AC coupling capacitor directly connected to the output terminal of the current-voltage converter that receives the corresponding voltage and generates an output voltage; an open-loop amplifier including a reset switch that amplifies the output voltage to generate an amplified output voltage; an event detection block that detects motion in relation to a change in the amplified output voltage and generates first and second detection signals; and a reset signal generator that generates a reset signal controlling operation of the reset switch in response to first and second control signals respectively related to the first and second detection signals. ### Claim 9 (depends on 8) The data processing system of claim 8, further comprising: an X-arbiter configured to receive the first detection signal, generate a corresponding first coordinate signal, and provide the first coordinate signal to the processor, wherein in response to the first coordinate signal the processor generates a first vision sensor pixel control signal and provides the first vision sensor pixel control signal to the X-arbiter, the X-arbiter being further configured in response to the first vision sensor pixel control signal to generate the first control signal; and a Y-arbiter configured to receive the second detection signal, generate a corresponding second coordinate signal, and provide the second coordinate signal to the processor, wherein in response to the second coordinate signal the processor generates a second vision sensor pixel control signal and provides the second vision sensor pixel control signal to the Y-arbiter, the Y-arbiter being further configured in response to the second vision sensor pixel control signal to generate the second control signal. ### Claim 10 (depends on 9) The data processing system of claim 9, wherein the current-voltage converter comprises: a bias circuit connected between a first line supplying an operating voltage and the output terminal of the current-voltage converter; a first transistor connected between the output terminal of the current-voltage converter and ground and including a gate connected to the photoelectric conversion element; and a second transistor connected between a second line and the photoelectric conversion element and including a gate connected to the output terminal of the current-voltage converter. ### Claim 11 (depends on 8) The data processing system of claim 8, wherein the first and second detection signals have the same phase. ### Claim 12 (depends on 8) The data processing system of claim 8, wherein the event detection block comprises: a switch signal generation circuit that generates an ON switch signal and an OFF switch signal respectively based on comparison results between the amplified output voltage and a first threshold voltage and a second threshold voltage having a different level that the first threshold voltage; and an event detection circuit that generates the first and second detection signals in response to one of the first and second control signals, the reset signal, the ON switch signal and the OFF switch signal. ### Claim 13 (depends on 12) The data processing system of claim 12, wherein the switch signal generation circuit comprises: a ON switch signal generator that compares the amplified output voltage with the first threshold voltage and outputs the ON switch signal; and an OFF switch signal generator that compares the amplified output voltage with the second threshold voltage and outputs the ON switch signal. ### Claim 14 (depends on 8) The data processing system of claim 8, wherein the reset signal generator comprises: a capacitor; a discharge circuit connected in parallel with the capacitor; and a switch circuit that in response to one of the first and second control signals supplies the other of the first and second control signals to the capacitor. ### Claim 15 (depends on 8) The data processing system of claim 8, wherein the vision sensor chip and the processor communicate via a camera serial interface (CSI). ### Claim 16 A method of operating the vision sensor chip, comprising: converting a current generated based on an incident light into a voltage; communicating the voltage directly to an AC coupling capacitor; amplifying an output voltage provided by the AC coupling capacitor using an open-loop amplifier including the reset switch; detecting motion in relation to a change in the amplified output voltage and generating first and second detection signals in response to the detecting of motion; and controlling operation of the reset switch with first and second control signals respectively related to the first and second detection signals. ### Claim 17 (depends on 16) The method of claim 16, wherein the first and second detection signals have the same phase. ### Claim 18 (depends on 17) The method of claim 17, wherein the first and second control signals have opposite phases. ### Claim 19 (depends on 16) The method of claim 16, wherein the generating of the first and second detection signals comprises: generating an ON switch signal and an OFF switch signal based by respectively comparing a first threshold voltages with the amplified output voltage, and comparing a second threshold voltage having a level different from the first threshold voltage with the amplified output voltage; and generating the first and second detection signals in response to at least one of the first and second control signals, the reset signal, the ON switch signal, and the OFF switch signal. ### Claim 20 (depends on 19) The method of claim 19, wherein the controlling of the operation of the reset switch comprises: forming a discharge path using a discharge circuit connected in parallel with the capacitor; and supplying, in response to one of the first and second control signals, the other of the first and second control signals to the capacitor.