Abstract: A transistor (M1) whose gate is capacitance-coupled to a wiring (L1) is connected between the wirings (L1, L2) connected to output nodes (OT1, OT2) outputting a reference voltage (VREF_OUT). A replica circuit (20) having a resistor (22) and a transistor (M2) connected in series is provided between the wirings (L1, L2). Gates of the transistors (M1, M2) are connected to each other. A differential amplifier (23) receives a voltage (V_RP) of a node (N1) between the resistor (22) and the transistor (M1) and a standard voltage (V_ID), and provides an output to the gate of the transistor (M2).

Abstract: A current is generated from a reference voltage using an operational amplifier. The current is mirrored by a current mirror circuit to obtain a reference current. For example, the current mirror circuit includes a plurality of PMOS transistors. Based on the result of measurement of the reference current by an external monitor, the connection destination of the gate voltage of each of a plurality of mirror destination current source transistors is switched by an analog switch circuit between a power supply and the gate of a mirror source current source transistor, thereby changing the number of mirror destination current source transistors which are turned on, to change a current minor ratio. Thus, the current can be trimmed.

Abstract: A semiconductor integrated circuit according to the present invention is equipped with a plurality of analog macros having comb capacitors (10), each comb capacitor (10) has a comb-shaped first electrode (11) and a comb-shaped second electrode (12), comb tooth portions (13) of the electrode (11) and comb tooth portions (14) of the electrode (12) are engaged so that the comb tooth portions (13) and the comb tooth portions (14) are arranged alternately and parallel to one another, and a comb tooth interval S of the comb capacitor is varied according to an absolute accuracy indicating an error between an actual capacitance value and an ideal capacitance value, or a relative accuracy indicating a difference in capacitance values between adjacent comb capacitors. Thereby, it is possible to provide a semiconductor integrated circuit which is equipped with highly-accurate analog macros and highly-integrated analog macros having comb capacitors which ensure high capacitance accuracies.

Abstract: An A/D converter which converts an analog input signal into a digital output signal by performing time-divisional parallel processings on the analog input signal using first and second pipeline type unit A/D converters. The A/D converter sets plural unit A/D converters performing parallel processings according to a system request, such that, when the A/D converter operates with a conversion frequency that is lower than the maximum conversion frequency, the unit A/D converter is halted by a control signal, thereby reducing inter-channel errors among the unit A/D converters to improve the precision of the A/D converter.

Abstract: A differential voltage interconnect (W101a) electrically connects the gate electrode of a transistor to be used among differential transistors (T101a, T101a, . . . ) to an input node receiving an input voltage (Vinn), and a differential voltage interconnect (W101b) electrically connects the gate electrode of a transistor to be used among differential transistors (T101b, T101b, . . . ) to an input node receiving an input voltage (Vinp). A bias voltage interconnect (W102) electrically connects the gate electrode of a transistor to be used among current source transistors (T102, T102, . . . ) to a bias node receiving a bias voltage (VBN), and a bias voltage interconnect (W103) electrically connects the gate electrodes of transistors to be used among load transistors (T103a, T103a, . . . , T103b, T103b, . . . ) to a bias node receiving a bias voltage (VBP).

Abstract: A differential voltage interconnect (W101a) electrically connects the gate electrode of a transistor to be used among differential transistors (T101a, T101a, . . . ) to an input node receiving an input voltage (Vinn), and a differential voltage interconnect (W101b) electrically connects the gate electrode of a transistor to be used among differential transistors (T101b, T101b, . . . ) to an input node receiving an input voltage (Vinp). A bias voltage interconnect (W102) electrically connects the gate electrode of a transistor to be used among current source transistors (T102, T102, . . . ) to a bias node receiving a bias voltage (VBN), and a bias voltage interconnect (W103) electrically connects the gate electrodes of transistors to be used among load transistors (T103a, T103a, . . . , T103b, T103b, . . . ) to a bias node receiving a bias voltage (VBP).

Abstract: In an A/D converter provided with an A/D converter circuit 101 for operationally amplifying an input signal and outputting an amplified signal, the A/D converter circuit 101 includes an initial value setting circuit 4a in addition to an amplifier 1a, a sub-A/D converter 2a, a sub-D/A converter 3a and capacitors C11 and C12. To ensure that the initial value of the output voltage of the amplifier 1a is a given voltage value close to the target value of operational amplification at the start of the operational amplification by the amplifier 1a, the initial value setting circuit 4a applies a given bias value equal to the given voltage value close to the target value to a next-stage capacitor C13 to be connected to the output side of the amplifier 1a. Such an A/D converter circuit 101 that can perform speedy convergence to the target value of operational amplification is used at each stage of a pipeline A/D converter.

Abstract: A semiconductor integrated circuit has a plurality of capacitor cells, and each capacitor cell has an upper electrode and a lower electrode. These electrodes are respectively connected to an upper electrode wiring and a lower electrode. When, for example, the upper electrode is connected to the upper electrode wiring and the electrode wiring is located at a side of the lower electrode of another capacitor cell or a side of the lower electrode wiring connecting these electrodes, a shield wiring is provided between the upper electrode wiring and the adjacently-located lower electrode of the other capacitor cell or between the upper electrode wiring and the adjacently-located lower electrode wiring. Thus, with this shield wiring, the capacitance coupling between each wiring of the capacitor cells and each upper electrode or each lower electrode of the capacitor cells are effectively suppressed.

Abstract: A semiconductor integrated circuit has a plurality of capacitor cells, and each capacitor cell has an upper electrode and a lower electrode. These electrodes are respectively connected to an upper electrode wiring and a lower electrode. When, for example, the upper electrode is connected to the upper electrode wiring and the electrode wiring is located at a side of the lower electrode of another capacitor cell or a side of the lower electrode wiring connecting these electrodes, a shield wiring is provided between the upper electrode wiring and the adjacently-located lower electrode of the other capacitor cell or between the upper electrode wiring and the adjacently-located lower electrode wiring. Thus, with this shield wiring, the capacitance coupling between each wiring of the capacitor cells and each upper electrode or each lower electrode of the capacitor cells are effectively suppressed.

Abstract: A differential voltage interconnect (W101a) electrically connects the gate electrode of a transistor to be used among differential transistors (T101a, T101a, . . . ) to an input node receiving an input voltage (Vinn), and a differential voltage interconnect (W101b) electrically connects the gate electrode of a transistor to be used among differential transistors (T101b, T101b, . . . ) to an input node receiving an input voltage (Vinp). A bias voltage interconnect (W102) electrically connects the gate electrode of a transistor to be used among current source transistors (T102, T102, . . . ) to a bias node receiving a bias voltage (VBN), and a bias voltage interconnect (W103) electrically connects the gate electrodes of transistors to be used among load transistors (T103a, T103a, T103b, T103b, . . . ) to a bias node receiving a bias voltage (VBP).

Abstract: An A/D converter which converts an analog input signal into a digital output signal by performing time-divisional parallel processings on the analog input signal using first and second pipeline type unit A/D converters (121,122), has a function of setting plural unit A/D converters which perform parallel processings according to a system request, and when the A/D converter is operated with a conversion frequency that is lower than the maximum conversion frequency, the unit A/D converter (122) is halted by a control signal (15), thereby reducing inter-channel errors among the unit A/D converters to improve the precision of the A/D converter.

Abstract: In an A/D converter provided with an A/D converter circuit 101 for operationally amplifying an input signal and outputting an amplified signal, the A/D converter circuit 101 includes an initial value setting circuit 4a in addition to an amplifier 1a, a sub-A/D converter 2a, a sub-D/A converter 3a and capacitors C11 and C12. To ensure that the initial value of the output voltage of the amplifier 1a is a given voltage value close to the target value of operational amplification at the start of the operational amplification by the amplifier 1a, the initial value setting circuit 4a applies a given bias value equal to the given voltage value close to the target value to a next-stage capacitor C13 to be connected to the output side of the amplifier 1a. Such an A/D converter circuit 101 that can perform speedy convergence to the target value of operational amplification is used at each stage of a pipeline A/D converter.

Abstract: In an A/D converter provided with an A/D converter circuit 101 for operationally amplifying an input signal and outputting an amplified signal, the A/D converter circuit 101 includes an initial value setting circuit 4a in addition to an amplifier 1a, a sub-A/D converter 2a, a sub-D/A converter 3a and capacitors C11 and C12. To ensure that the initial value of the output voltage of the amplifier 1a is a given voltage value close to the target value of operational amplification at the start of the operational amplification by the amplifier 1a, the initial value setting circuit 4a applies a given bias value equal to the given voltage value close to the target value to a next-stage capacitor C13 to be connected to the output side of the amplifier 1a. Such an A/D converter circuit 101 that can perform speedy convergence to the target value of operational amplification is used at each stage of a pipeline A/D converter.

Abstract: In an A/D converter provided with an A/D converter circuit 101 for operationally amplifying an input signal and outputting an amplified signal, the A/D converter circuit 101 includes an initial value setting circuit 4a in addition to an amplifier 1a, a sub-A/D converter 2a, a sub-D/A converter 3a and capacitors C11 and C12. To ensure that the initial value of the output voltage of the amplifier 1a is a given voltage value close to the target value of operational amplification at the start of the operational amplification by the amplifier 1a, the initial value setting circuit 4a applies a given bias value equal to the given voltage value close to the target value to a next-stage capacitor C13 to be connected to the output side of the amplifier 1a. Such an A/D converter circuit 101 that can perform speedy convergence to the target value of operational amplification is used at each stage of a pipeline A/D converter.

Abstract: In a charge redistribution type A/D converter, an input-side capacitor terminal and a comparator-side capacitor terminal are connected through first and second analog switches to a fixed-voltage supply circuit, and the input-side capacitor terminal is connected through a third analog switch to the outside. Immediately before sampling an analog signal, the first and second analog switches are closed while the third analog switch is opened, according to a RESET signal. Thereby, fixed voltages are supplied to the input-side capacitor terminal and the comparator-side capacitor terminal, respectively, and charge stored in a weighting capacitor unit is initialized to a predetermined value.

Abstract: A semiconductor integrated circuit has a plurality of capacitor cells, and each capacitor cell has an upper electrode and a lower electrode. These electrodes are respectively connected to an upper electrode wiring and a lower electrode. When, for example, the upper electrode is connected to the upper electrode wiring and the electrode wiring is located at a side of the lower electrode of another capacitor cell or a side of the lower electrode wiring connecting these electrodes, a shield wiring is provided between the upper electrode wiring and the adjacently-located lower electrode of the other capacitor cell or between the upper electrode wiring and the adjacently-located lower electrode wiring. Thus, with this shield wiring, the capacitance coupling between each wiring of the capacitor cells and each upper electrode or each lower electrode of the capacitor cells are effectively suppressed.

Abstract: In a charge redistribution type A/D converter, an input-side capacitor terminal and a comparator-side capacitor terminal are connected through first and second analog switches to a fixed-voltage supply circuit, and the input-side capacitor terminal is connected through a third analog switch to the outside. Immediately before sampling an analog signal, the first and second analog switches are closed while the third analog switch is opened, according to a RESET signal. Thereby, fixed voltages are supplied to the input-side capacitor terminal and the comparator-side capacitor terminal, respectively, and charge stored in a weighting capacitor unit is initialized to a predetermined value.

Abstract: A semiconductor integrated circuit has a plurality of capacitor cells, and each capacitor cell has an upper electrode and a lower electrode. These electrodes are respectively connected to an upper electrode wiring and a lower electrode. When, for example, the upper electrode is connected to the upper electrode wiring and the electrode wiring is located at a side of the lower electrode of another capacitor cell or a side of the lower electrode wiring connecting these electrodes, a shield wiring is provided between the upper electrode wiring and the adjacently-located lower electrode of the other capacitor cell or between the upper electrode wiring and the adjacently-located lower electrode wiring. Thus, with this shield wiring, the capacitance coupling between each wiring of the capacitor cells and each upper electrode or each lower electrode of the capacitor cells are effectively suppressed.

Abstract: The present invention provides a serial/parallel A/D converter which is capable of performing a high-speed and high-accuracy operation even in the case where an analog input voltage Vin greatly varies in a period between a previous sampling period in which the analog input voltage is held and the next sampling period, when converting the analog input voltage Vin input into a digital value. This serial/parallel A/D converter includes a lower-order reference voltage initializing circuit 8 for initializing a lower-order reference voltage to an initialization voltage Vrc 23.

Abstract: When the performance of an A/D converter required by a system changes, power consumption of the overall system can be reduced. The resolution of an A/D converter is made variable by changing a current flowing through an amplifier by an external control signal that specifies the resolution. Thus, when the performance required by a system changes, it is possible to change the performance of the A/D converter and to prevent a performance overhead of the A/D converter. Consequently, power consumption of the A/D converter is reduced, and power consumption of the system as a whole is also reduced.