摘要:
A semiconductor device of the invention has a plurality of resistor elements formed on an element isolating oxide film in predetermined regions on a surface of a semiconductor substrate. Active regions are furnished close to the resistor elements. This allows the element isolating oxide film near the resistor elements to be divided into suitable strips, forestalling a concave formation at the center of the element isolating oxide film upon polishing of the film by CMP and thereby enhancing dimensional accuracy of the resistor elements upon fabrication.
摘要:
An A/D converter simplifies its circuit configuration without deteriorating accuracy in A/D conversion. A circuit is formed of a folding and interpolation type. A gain-variable pre-amplifier group 11 amplifies each of reference voltages Vref1 to VrefN and an analog input voltage Vin, to output the result to a folding amplifier group 12, while a gain-variable pre-amplifier group 21 amplifies each of reference voltages Vrr1 to VrrJ and the analog input voltage Vin, to output the result to a comparator group 24. Each of pre-amplifiers constituting the gain-variable pre-amplifier groups 11 and 21 has an amplification factor that varies in upper and lower comparison periods according to a clock control signal .PHI.cnt.
摘要:
An A/D converter includes a sample-hold circuit, A/D converting stages connected in series to the sample-hold circuit, and an encoder/latch circuit which adds 3-bit digital signals issued from the A/D converting stages to each other for outputting a signal of 9 bits. The sample-hold circuit and the A/D converting stages each include a differential amplifier. Differential outputs of each differential amplifier are short-circuited for a predetermined initial period in each sampling period.
摘要:
In a pipeline type A/D converter, a sample/hold.cndot.subtracter circuit of an A/D converter block of a first stage samples an analog voltage and outputs an offset voltage at a first phase, and subtracts an output voltage of an A/D converter from the sampled analog voltage in a second phase. An A/D converter of an A/D converter block of a succeeding stage subtracts the output voltage of the sample/hold.cndot.subtracter circuit of the first phase from the output voltage of the sample hold.cndot.subtracter circuit of the second phase, and converts the subtracted result into a digital code. The influence of an offset of a differential amplifier included in the sample/hold.cndot.subtracter circuit is removed so that A/D conversion of high accuracy is allowed.
摘要:
A high-performance differential latch circuit which includes a differential amplifier circuit comprised of an NMOS transistor (27) serving as a constant current source, PMOS transistors (3, 4) and NMOS transistors (23,24), a latch circuit comprised of NMOS transistors (25, 26), and a switch circuit comprised of NMOS transistors (21,22,28) for alternately operating the differential amplifying function and latch function, the transistor (27) serving as the constant current source having a drain terminal directly connected to the transistors (23,24) and a source terminal directly connected to a ground voltage (2), whereby the differential latch circuit differentially amplifies the signals without the loss of the constant current source function during the differential amplification.
摘要:
An upper comparator group compares an analog signal with upper reference potentials applied from upper ladder resistance network. A switch group outputs the predetermined intermediate reference potential of the ladder resistance network to an analog subtracting circuit in response to the upper comparison results. The analog subtracting circuit subtracts the intermediate reference potential from the analog signal for producing an input signal for use in the lower side. A lower ladder resistance network outputs lower reference potentials obtained by dividing by resistors constant static intermediate reference potentials of the ladder resistance network applied from a differential amplifying circuit. A lower comparator group compares the lower reference potentials with the input signal for lower comparison. The upper and the lower comparison results are converted into a digital signal by upper and the lower encoders and the adding/subtracting circuit.
摘要:
An A/D converter main body is formed in the form of an annulus with a wiring region set as its center, and a ladder resistor array for dividing an input reference voltage and an analog signal line for applying an input analog signal to each comparator in the A/D converter are formed in the form of an annulus with the wiring region set as a center. Wirings from terminals are once concentrated into the wiring region by an input/output line group and then distributed therefrom to circuit elements. Since the ladder resistor array is formed in a circular form, resistance values are less liable to change as compared to the case where the ladder resistor array is bent, resulting in a higher precision of reference voltages for comparison. Further, wiring lengths for control signals to be applied to the circuit elements are made equal, and there is no fear of line delays in the control signals.
摘要翻译:A / D转换器主体形成为以布线区域为中心的环形的形式,以及用于分割输入参考电压的梯形电阻阵列和用于将输入的模拟信号施加到每个比较器的模拟信号线 A / D转换器形成为以布线区域为中心的环形的形式。 来自端子的布线一旦通过输入/输出线组集中到布线区域中,然后从电缆元件分布。 由于梯形电阻器阵列形成为圆形形式,所以与梯形电阻器阵列弯曲的情况相比,电阻值不易变化,因此比较了较高的基准电压精度。 此外,使施加到电路元件的控制信号的布线长度相等,并且不必担心控制信号中的线路延迟。
摘要:
A comparator bank of an A/D converter comprising a plurality of comparators arranged into rows in a folded-back shape and a supply voltage line and a ground line in parallel with each other and connected to the comparators to provide reference potentials thereto according to a distribution shape which rises and falls continuously along the rows of the comparators whereby the linearity of the A/D converter is effectively maintained. The nodes of the comparators do not intersect and are arranged to successively become further from reference points set at the terminals of the supply voltage and ground lines.
摘要:
A semiconductor device of the invention has a plurality of resistor elements formed on an element isolating oxide film in predetermined regions on a surface of a semiconductor substrate. Active regions are furnished close to the resistor elements. This allows the element isolating oxide film near the resistor elements to be divided into suitable strips, forestalling a concave formation at the center of the element isolating oxide film upon polishing of the film by CMP and thereby enhancing dimensional accuracy of the resistor elements upon fabrication.
摘要:
A semiconductor device of the invention has a plurality of resistor elements formed on an element isolating oxide film in predetermined regions on a surface of a semiconductor substrate. Active regions are furnished close to the resistor elements. This allows the element isolating oxide film near the resistor elements to be divided into suitable strips, forestalling a concave formation at the center of the element isolating oxide film upon polishing of the film by CMP and thereby enhancing dimensional accuracy of the resistor elements upon fabrication.