A circuit includes first and second power nodes having differing first and second voltage levels, and a reference node having a reference voltage level. A master latch outputs a first data bit based on a received data bit; a slave latch includes a first inverter that outputs a second data bit based on the first data bit and a second inverter that outputs an output data bit based on a selected one of the first data bit or a third data bit; a level shifter outputs the third data bit based on a fourth data bit; and a retention latch outputs the fourth data bit based on the second data bit. The first and second inverters and the level shifter are coupled between the first power node and the reference node, and the retention latch includes a plurality of transistors coupled between the second power node and the reference node.

A flip-flop circuit configured to latch an input signal to an output signal is disclosed. The circuit includes a first latch circuit; and a second latch circuit coupled to the first latch circuit. In some embodiments, in response to a clock signal, the first and second latch circuits are complementarily activated so as to latch the input signal to the output signal, and the first and second latch circuits each comprises at most two transistors configured to receive the clock signal.

A true single-phase clock (TSPC) D flip-flop includes four stages. The four stages are serially connected between the input terminal and the output terminal of the TSPC D-type flip-flop. Each stage is selectively equipped with two connecting devices. One of the two connecting devices is a resistive element. The other of the two connecting devices is a short circuit element. When the node between two stages is in the floating state, the voltage change is slowed down by the resistive element. Consequently, the possibility of causing the function failure of the D-type flip-flop is minimized.

A low power flip-flop includes first to fourth signal generation circuits and an inverter. The first signal generation circuit receives the clock signal, the data input signal, and a first internal signal that is an output of the second signal generation circuit and generates a second internal signal. The inverter receives the first internal signal and generates an inverted first internal signal. The second signal generation circuit receives the first internal signal and the output signal that is an output of the third signal generation circuit, and generates the inverted output signal. The third signal generation circuit receives the clock signal and the inverted output signal and generates the output signal. The fourth signal generation circuit receives the inverted first internal signal, the second internal signal, and the clock signal and generates the first internal signal.

A flip-flop circuit includes first and second latches. The first latch comprises a first inverting logic element and a second inverting logic element. The first inverting logic element has a first logic threshold voltage. The second inverting logic element is connected in antiparallel to the first inverting logic element and has a second logic threshold voltage. The first and second logic threshold voltages are set with respect to one half of a power supply voltage. The second latch comprises a third inverting logic element and a fourth inverting logic element. The third inverting logic element is connected to the first latch and has a third logic threshold voltage. The fourth inverting logic element is connected in antiparallel to the third inverting logic element and has a fourth logic threshold voltage. The third and fourth logic threshold voltages are set with respect to one half of the power supply voltage.

A level shifter and a chip with the level shifter are shown. Between the input pair and the cross-coupled output pair, there are a first protection circuit and a second protection circuit. An overdrive voltage, which is double the nominal voltage of the level shifter plus a delta voltage, is applied to the level shifter. The first protection circuit has a first voltage-drop circuit that compensates for the delta voltage. The second protection circuit has a second voltage-drop circuit that compensates for the delta voltage.

A flip-flop circuit includes first and second latches. The first latch comprises a first inverting logic element and a second inverting logic element. The first inverting logic element has a first logic threshold voltage. The second inverting logic element is connected in antiparallel to the first inverting logic element and has a second logic threshold voltage. The first and second logic threshold voltages are set with respect to one half of a power supply voltage. The second latch comprises a third inverting logic element and a fourth inverting logic element. The third inverting logic element is connected to the first latch and has a third logic threshold voltage. The fourth inverting logic element is connected in antiparallel to the third inverting logic element and has a fourth logic threshold voltage. The third and fourth logic threshold voltages are set with respect to one half of the power supply voltage.

An object is to provide a semiconductor device which can suppress characteristic deterioration in each transistor without destabilizing operation. In a non-selection period, a transistor is turned on at regular intervals, so that a power supply potential is supplied to an output terminal of a shift register circuit. A power supply potential is supplied to the output terminal of the shift register circuit through the transistor. Since the transistor is not always on in a non-selection period, a shift of the threshold voltage of the transistor is suppressed. In addition, a power supply potential is supplied to the output terminal of the shift register circuit through the transistor at regular intervals. Therefore, the shift register circuit can suppress noise which is generated in the output terminal.

Disclosed herein are silicon-on-insulator (SOI) switches and associated control circuits having level shifters configured to provide increased voltages (positive and/or negative) to the switches. The disclosed level shifters can be configured to provide increased voltages and can be used with high-linearity switches and/or can improve the linearity of switches. The improved switch performance can improve front end module performance for applications such as carrier aggregation (CA) and multiple input multiple output (MIMO) as well as with protocols such as Long-Term Evolution Advanced (or LTE-A).

A flip flop includes a precharge circuit configured to charge a first node by bridging a power voltage node and the first node, the charging of the first node by the precharge circuit according to a voltage level of a clock signal, the charging of the first node by the precharge circuit based on at least two PMOS transistors arranged in series, a discharge circuit configured to discharge the first node by bridging the first node and a ground node, the discharging of the first node according to an input signal and the clock signal, and a second node configured to be charged or discharged, the charging and the discharging of the second node according to a voltage level of the first node.