Lamp generator and image sensing device including the same

Abstract

A ramp generator is provided that allows for an increase in the swing range of the ramp signal. [Solution] The lamp generator 10 has multiple control signals CON <n:0>Based on this, the current value of the reference current IREF applied to the first node ND1 is adjusted, and multiple control signals CON are used. <n:0>The system may include a current control unit 300 that controls the current value of the current applied to the second node ND2 based on some of the control signals, a bias voltage generation unit 500 that generates bias voltages VBIAS1 and VBIAS2 based on currents mirrored according to the first node ND1 and the second node ND2, and a ramp signal generation unit 600 that generates a ramp signal VRAMP based on the bias voltages VBIAS1 and VBIAS2.< / n:0>

Claims

1. A current control unit that adjusts the current value of a reference current applied to a first node based on multiple control signals, and controls the current value of a current applied to a second node based on some of the control signals among the multiple control signals, A bias voltage generation unit that generates a bias voltage based on currents mirrored according to the first node and the second node, A lamp signal generation unit that generates a lamp signal based on the bias voltage, A lamp generator, including...

2. The ramp generator according to claim 1, wherein the aforementioned partial control signals are the higher bits of the plurality of control signals.

3. The current control unit, A current steering unit that adjusts the amount of current applied to the first node based on the plurality of control signals, A current adjustment unit that adjusts the current value applied to the second node based on the aforementioned control signals, The lamp generator according to claim 1, further comprising: a first current mirroring unit that mirrors the current of the first node and the current of the second node.

4. The current steering unit is Multiple transistors connected in parallel to the power supply voltage application terminals, to which a reference voltage is applied via a common gate terminal, The lamp generator according to claim 3, further comprising: a plurality of switches connected between the plurality of transistors and the first node, the switching operation of which is selectively controlled by the plurality of control signals.

5. The current steering unit is The lamp generator according to claim 4, wherein the current value applied to the first node is controlled via the plurality of transistors having different sizes corresponding to the number of turns on of the plurality of switches.

6. The current adjustment unit is, Multiple transistors connected in parallel to the power supply voltage application terminals, to which a reference voltage is applied via a common gate terminal, The lamp generator according to claim 3, further comprising: a plurality of switches connected between the plurality of transistors and the second node, the switching operation of which is selectively controlled by some of the control signals.

7. The current adjustment unit is, The lamp generator according to claim 6, wherein the current value applied to the second node is controlled via the plurality of transistors having different sizes corresponding to the number of turns on the plurality of switches.

8. The first current mirror section is, A first transistor is connected between the first node and the third node, with its gate terminal connected to the second node, A second transistor is connected between the third node and the ground voltage terminal, and its gate terminal is connected to the first node, The lamp generator according to claim 3, comprising a third transistor connected between the second node and the ground voltage terminal, the gate terminal of which is connected to the second node.

9. The first current mirror section is, A fourth transistor is connected between the first node and the third node, with its gate terminal connected to the second node, A fifth transistor is connected between the third node and the ground voltage terminal, and its gate terminal is connected to the first node, A sixth transistor is connected between the second node and the fourth node, with its gate terminal connected to the second node, The lamp generator according to claim 3, further comprising a seventh transistor connected between the fourth node and the ground voltage terminal, with its gate terminal connected to the second node.

10. The bias voltage generation unit is, A second current mirror unit that mirrors the currents applied from the first node and the second node, The lamp generator according to claim 1, further comprising a voltage control unit that generates the bias voltage based on the current of the second current mirror unit.

11. The second current mirror section is, An eighth transistor is connected between the fifth node and the sixth node, with its gate terminal connected to the second node, A ninth transistor is connected between the sixth node and the ground voltage terminal, and its gate terminal is connected to the first node, A 10th transistor is connected between the 7th node and the 8th node, with its gate terminal connected to the 2nd node, The lamp generator according to claim 10, further comprising: an eleventh transistor connected between the eighth node and the ground voltage terminal, with its gate terminal connected to the first node.

12. The voltage control unit, A 12th transistor is connected between the power supply voltage application terminal and the 9th node, and its gate terminal is connected to the 5th node. A 13th transistor is connected between the 9th node and the 5th node, with its gate terminal connected to the 5th node, The lamp generator according to claim 11, further comprising a 14th transistor connected between the power supply voltage application terminal and the 7th node, the gate terminal of which is connected to the 7th node.

13. The voltage control unit, A 15th transistor is connected between the power supply voltage application terminal and the 5th node, and its gate terminal is connected to the 5th node. A 16th transistor is connected between the power supply voltage application terminal and the 10th node, and its gate terminal is connected to the 7th node. The lamp generator according to claim 11, further comprising a 17th transistor connected between the 10th node and the 7th node, with its gate terminal connected to the 5th node.

14. The lamp signal generation unit, A lamp cell that generates the lamp signal based on the bias voltage and switch control signal, The lamp generator according to claim 1, further comprising a load unit for controlling the loading of the lamp signal.

15. The lamp generator according to claim 14, wherein the lamp cells are a plurality and share the load section.

16. The aforementioned lamp cell is A 18th transistor is connected between the power supply voltage application terminal and the 11th node, and its gate terminal is connected to the 5th node. A 19th transistor is connected between the 11th node and the 12th node, and its gate terminal is connected to the 7th node, A first switch is connected between the 12th node and the ground voltage terminal, and its switching operation is controlled by a first switch control signal. The lamp generator according to claim 14, further comprising a second switch connected between the 12th node and the load unit, the switching operation of which is controlled by a second switch control signal.

17. The aforementioned load section is The lamp generator according to claim 14, further comprising a variable resistor connected between the lamp cell and the ground voltage terminal.

18. A control unit that generates the plurality of control signals and a switch control signal for controlling the lamp signal generation unit, A current generation unit that generates the reference current based on the bandgap reference voltage, The lamp generator according to claim 1, further comprising a bandgap reference circuit for generating the bandgap reference voltage.

19. A pixel array that converts incident light into electrical signals and outputs pixel signals, A lamp generator that adjusts the current value of a reference current applied to a first node based on multiple control signals, controls the current value of a current applied to a second node based on control signals of some of the higher bits of the multiple control signals, and generates a lamp signal based on the mirrored currents according to the first and second nodes. An analog-to-digital converter that outputs analog-to-digital conversion data based on the aforementioned pixel signal and the aforementioned ramp signal, A timing controller that generates the aforementioned plurality of control signals, An image sensing device, including [a specific feature].

20. The aforementioned lamp generator, A current control unit that adjusts the current value of a reference current applied to the first node based on the plurality of control signals, and controls the current value of a current applied to the second node based on the control signals of some bits, A bias voltage generation unit that generates a bias voltage based on the mirrored current, The image sensing apparatus according to claim 19, comprising: a ramp signal generation unit that generates the ramp signal based on the bias voltage and controls the offset of the ramp signal based on a switch control signal applied from the timing controller.

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