A gate voltage bootstrap switching circuit includes an LDO, a first MOS transistor, a second MOS transistor, a third MOS transistor, and a voltage control unit. The LDO has an inverting input terminal of connected to its output terminal. Drain of the first MOS transistor and source of the third MOS transistor are connected to the output terminal, source of the first MOS transistor is connected to drain of the second MOS transistor, and source of the second MOS transistor is connected to drain of the third MOS transistor. Capacitor arrays are connected. The voltage control unit is connected to gates of the first, second, and third MOS transistors to input an external power supply voltage as a gate-source voltage to the MOS transistors. The circuit eliminates the non-linearity of the impedance of the switch MOS transistors and improves the conversion speed of the ADC.

A complementary current-steering digital-to-analog converter (DAC) including a p-type DAC as well as an n-type DAC is shown. The p-type DAC has p-type current sources, and the n-type DAC has n-type current sources. The p-type and n-type current sources are coupled to a first input terminal or a second input terminal of a transimpedance amplifier (TIA) according to the digital input of the complementary current-steering DAC. In response to the digital input changing from a first value to a second value that is greater than the first value, one or more n-type current sources connected to the second input terminal of the TIA are switched so that they are connected to the first input terminal of the TIA.

Certain aspects of the present disclosure are directed towards a digital-to-analog converter (DAC) system. The DAC system generally includes a first driver and a plurality of current-steering cells. A first current-steering cell of the plurality of current-steering cells includes: a first current source coupled to a first current-steering transistor and a second current-steering transistor, wherein a gate of the first current-steering transistor and a gate of the second current-steering transistor are coupled to a first output and a second output of the first driver, respectively; a first transistor having a source coupled to a current source path and a drain coupled to a reference potential node; and a second transistor having a source coupled to the current source path and a drain coupled to the reference potential node.

Semiconductor devices and methods are provided. A semiconductor device according to the present disclosure includes a substrate having a first area and a second area, a plurality of fin structures extending along a direction over the first area and the second area of the substrate, a first transistor and a second transistor in the first area, a first isolation structure disposed between the first transistor and the second transistor, a first isolation structure disposed between the first transistor and the second transistor, a third transistor and a fourth transistor in the second area, and a second isolation structure disposed between the third transistor and the fourth transistor. The first isolation structure includes a first width along the direction and the second isolation structure includes a second width along the direction. The second width is greater than the first width.

A tri-level digital-to-analog converter (DAC) element includes a first DAC cell. The first DAC cell includes a first reference circuit, a second reference circuit, and a switch circuit. The first reference circuit provides a first reference signal. The second reference circuit provides a second reference signal. The first switch circuit receives a control input from an input port of the tri-level DAC element, and controls interconnection between the first reference circuit, the second reference circuit, and an output port of the tri-level DAC element according to the control input. During a period in which the tri-level DAC element operates in a 0 state, the first switch circuit is arranged to couple at least one of the first reference circuit and the second reference circuit to the output port of the tri-level DAC element.

A multi-level digital-to-analog converter (DAC) element includes a first DAC cell. The first DAC cell includes a first reference circuit, a second reference circuit, and a switch circuit. The first reference circuit provides a first reference signal. The second reference circuit provides a second reference signal. The first switch circuit receives a control input from an input port of the multi-level DAC element, and controls interconnection between the first reference circuit, the second reference circuit, and an output port of the multi-level DAC element according to the control input. During a period in which the multi-level DAC element operates in a O state, the first switch circuit is arranged to couple at least one of the first reference circuit and the second reference circuit to the output port of the multi-level DAC element.