Semiconductor circuit, imaging device, and electronic device
Provided is a semiconductor circuit that includes a first transistor that switches whether to acquire an input signal into a first node, a second transistor having at least one of a source and a drain that are connected to the first node, and a third transistor that switches whether the first node and a second node are to be electrically short-circuited or cut off from each other, wherein the state of the second transistor makes a transition to have a gate waveform opposite in phase to the gate waveform of a first transistor after the timing of a transition of the first transistor from an on-state to an off-state, and the third transistor makes a transition from an on-state to an off-state after the timing of the state transition of the second transistor.
1 . A semiconductor circuit, comprising:
a first transistor connected to a first node, wherein the first transistor is configured to:
transition from an on-state to an off-state; and
control transmission of an input signal to the first node based on the transition of the first transistor from the on-state to the off-state;
a second transistor configured to switch between an off-state and an on-state, wherein
the second transistor includes a source and a drain, and
each of the source of the second transistor and the drain of the second transistor is connected to the first node; and
a third transistor configured to transition from an on-state to an off-state, wherein
the third transistor includes a source and a drain,
the source of the third transistor is connected to the first node,
the drain of the third transistor is connected to a second node,
the second node is different from the first node,
based on the transition of the third transistor from the on-state to the off-state, the first node is one of electrically short circuit from the second node or electrically cut off from the second node,
the switch of the second transistor between the on-state and the off-state is associated with a gate waveform of the second transistor,
the gate waveform of the second transistor is opposite in phase to a gate waveform of the first transistor at a first time period,
the first time period is a time period after the transition of the first transistor from the on-state to the off-state,
the transition of the third transistor from the on-state to the off-state after timing of is at a second time period, and
the second time period is a time period after the switch of the second transistor between the off-state and the on-state.
2 . The semiconductor circuit according to claim 1 , further comprising a cancelling switch that includes the second transistor, wherein
the second transistor is further configured to cancel potential fluctuations of the first node, and
the potential fluctuations are based on charge injection and clock feedthrough at a time of the transition of the first transistor from the on-state to the off-state.
3 . The semiconductor circuit according to claim 1 , wherein
the first transistor includes a drain and a source,
the drain of the first transistor is connected to the first node, and
the source of the first transistor is configured to receive the input signal.
4 . The semiconductor circuit according to claim 3 , wherein
each of the first transistor and the third transistor is a PMOS (P-channel Metal-Oxide-Semiconductor) transistor,
the second transistor is one of the PMOS transistor or an NMOS (N-channel Metal-Oxide-Semiconductor) transistor,
based on the second transistor is the PMOS transistor,
the second transistor is further configured to transition from the off-state to the on-state at the first time period, and
the third transistor is further configured to transition from the on-state to the off-state at the second time period, and
based on the second transistor is the NMOS transistor,
the second transistor is further configured to transition from the on-state to the off-state at the first time period, and
the third transistor is further configured to transition from the on-state to the off-state at the second time period.
5 . The semiconductor circuit according to claim 1 , wherein
the first transistor includes a drain and a source,
the drain of the first transistor is connected to the second node, and
the source of the first transistor is configured to receive the input signal.
6 . The semiconductor circuit according to claim 5 , wherein
each of the first transistor and the third transistor is an NMOS (N-channel Metal-Oxide-Semiconductor) transistor,
the second transistor is one of the NMOS transistor or a PMOS (P-channel Metal-Oxide-Semiconductor),
based on the second transistor is the NMOS transistor,
the second transistor is further configured to transition from the off-state to the on-state at the first time period, and
the third transistor is further configured to transition from the on-state to the off-state at the second time period, and
based on the second transistor is the PMOS transistor,
the second transistor is further configured to transition from the on-state to the off-state at the first time period, and
the third transistor is further configured to transition from the on-state to the off-state at the second time period.
7 . The semiconductor circuit according to claim 1 , wherein
the second node, after the transition of the third transistor form the on-state to the off-state, is at a specific potential, and
the specific potential is independent of a gate potential of the second transistor.
8 . The semiconductor circuit according to claim 1 , further comprising:
a fourth transistor includes a drain, a source, and a gate, wherein the gate of the fourth transistor is connected to the second node; and
a capacitor connected between the gate of the fourth transistor and a reference potential node, wherein the reference potential node is different from each of the first node and the second node.
9 . The semiconductor circuit according to claim 8 , wherein the capacitor is configured to store a charge corresponding to the input signal at a time of the transition of the first transistor from the on-state to the off-state.
10 . The semiconductor circuit according to claim 8 , wherein
the capacitor is connected between the second node and a third node,
the third node is different from the each of the first node and the second node, and
a gate potential of the third transistor is at a potential of the third node, based on the third transistor is in the off-state.
11 . The semiconductor circuit according to claim 8 , wherein
the fourth transistor further includes a source,
the source of the fourth transistor is connected to a signal line, and
the signal line is configured to transmit a pixel signal.
12 . The semiconductor circuit according to claim 8 , further comprising a current source that includes the fourth transistor.
13 . The semiconductor circuit according to claim 8 , further comprising a differential amplifier, wherein
the differential amplifier includes a fifth transistor and a sixth transistor,
the fifth transistor and the fourth transistor are a differential pair,
the fifth transistor includes a source and a drain, and
the sixth transistor is configured to control a current between each of the drain of the fourth transistor, the drain of the fifth transistor, the source of the fourth transistor, and the source of the fifth transistor.
14 . The semiconductor circuit according to claim 1 , wherein each of the first transistor, the second transistor, and the third transistor are of a specific conductivity type.
15 . The semiconductor circuit according to claim 1 , wherein
each of the first transistor and the third transistor is of a first conductivity type,
the second transistor is of a second conductivity type, and
the first conductivity type is different from the second conductivity type.
16 . The semiconductor circuit according to claim 15 , wherein
the first transistor includes a source and a drain,
the source of the first transistor is connected to the source of the second transistor, and
the drain of the first transistor is connected to the drain of the second transistor.
17 . The semiconductor circuit according to claim 1 , further comprising a switching control circuit configured to:
control the second transistor to switch between the on-state and the off-state at the first time period; and
control the third transistor to transition from the on-state to the off-state at the second time period.
18 . An imaging device, comprising:
a pixel array part that includes a plurality of pixels, wherein
the plurality of pixels includes a plurality of photoelectric conversion units, and
the plurality of photoelectric conversion units is in a two-dimensional array;
a plurality of signal lines configured to transmit a plurality of pixel signals, wherein the plurality of pixels is configured to perform photoelectric conversion on the plurality of pixel signals;
an internal voltage generation circuit configured to generate a bias voltage;
a sample hold circuit configured to sample the bias voltage in a first time period and hold the bias voltage in the first time period;
a current source configured to control a current through the plurality of signal lines based on the held bias voltage; and
an AD converter configured to generate, based on a result of comparison between each of the plurality of pixel signals and a reference signal, a plurality of digital signals corresponding to the plurality of pixel signals, wherein
the plurality of pixel signals is on the plurality of signal lines, and
the sample hold circuit includes:
a first transistor connected to a first node, wherein the first transistor is configured to:
transition from an on-state to an off-state; and
control transmission of an input signal to the first node based on the transition of the first transistor from the on-state to the off-state;
a second transistor configured to switch between an off-state and an on-state, wherein
the second transistor includes a source and a drain, and
each of the source of the second transistor and the drain of the second transistor is connected to the first node; and
a third transistor configured to transition from an on-state to an off-state, wherein
the third transistor includes a source and a drain,
the source of the third transistor is connected to the first node,
the drain of the third transistor is connected to a second node,
the second node is different from the first node,
based on the transition of the third transistor from the on-state to the off-state, the first node is one of electrically short circuit from the second node or electrically cut off from the second node,
the switch of the second transistor between the on-state and the off-state is associated with a gate waveform of the second transistor,
the gate waveform of the second transistor is opposite in phase to a gate waveform of the first transistor at a second time period,
the second time period is a time period after the transition of the first transistor from the on-state to the off-state,
the transition of the third transistor from the on-state to the off-state is at a third time period, and
the third time period is a time period after the switch of the second transistor between the off-state and the on-state.
19 . The imaging device according to claim 18 , wherein
the current source includes a plurality of transistors corresponding to the plurality of signal lines,
each of the first transistor, the second transistor, and the third transistor is different from the plurality of transistors,
each of the plurality of transistors includes a respective drain, and
the respective drain of the each of the plurality of transistors is connected to a respective signal line of the plurality of signal lines.
20 . An electronic device, comprising:
the imaging device according to claim 18 , wherein the imaging device is configured to output the plurality of digital signals; and
a signal processing unit configured to perform a signal processing process based on the plurality of digital signals.