模数的

Figure 5 is the schematic diagram of a d/a converter.

图5是数/模转换器的原理图

First it produces the pulse signal by the multivibratorwhich is consisted of 555 timer and send in the detecting coil to form the alternating magnetic field, then it asopts UGN3503 linear half-effect as prode to the magnetic field change into the voltage signal change,after enlargement electric circuit and peak value examination electric circuit,the signal be treated to send into ADC0809 modulus converter change moduluses, then the digital signal after the modulus converter is changed is sent into AT89C51one-chip computers afterwards, after the digital filter, AT89C51one-chip computers afterwards compares the data to the reference voltage and judges whether to have detected the metal and alarm.

这个系统是以AT89C51单片机为核心，首先由555定时器构成多谐振荡器产生脉冲信号送入探测线圈以形成交变磁场，然后经过线性霍尔器件UGN3503将磁场变化转换为电压信号的变化，经过放大电路和峰值检测电路，经数模转换之后输入到单片机中，由单片机对数据进行软件滤波之后，与基准值比较之后，判断是否存在金属和报警显示。

For the designed digital controller, the hybrid digital/analog computer simulation of the robust active suspension system is carried out and simulation results are given.

对设计出的数字控制器应用数模混合仿真方法对主动悬挂鲁棒控制系统进行了试验模拟。

ABSTRACT: With the development of the times, digital electronic technology has been popular in all of our lives, work, research, and all fields. This paper introduces a NC DC power supply, the power consists of analogue power supply, display circuit, control circuit, digital-to-analog converter and circuit amplifier.

随着时代的发展，数字电子技术已经普及到我们生活，工作，科研，各个领域，本文将介绍一种数控稳压电源，本电源由模拟电源、显示电路、控制电路、数模转换电路、放大电路五部分组成。

ABSTRACT: With the development of the times, digital electronictechnology has been popular in all of our lives, work, research,and all fields. This paper introduces a NC DC power supply, thepower consists of analogue power supply, display circuit, controlcircuit, digital-to-analog converter and circuit amplifier.

随着时代的发展，数字电子技术已经普及到我们生活，工作，科研，各个领域，本文将介绍一种数控稳压电源，本电源由模拟电源、显示电路、控制电路、数模转换电路、放大电路五部分组成。

Stepper motor is a pulse will be transferred into angular displacement of the Electrical and Mechanical-DAC devices.

步进电机是一个将脉冲信号转移成角位移的机电式数模转换器装置。

The tone generator task arithmetically forms tone waveform data by use of the tone controlling parameters and passes the tone waveform data to a CODEC circuit functioning as an A/D converter.

该乐音发生器任务利用乐音控制参数用算术方法形成乐音波形数据并把该乐音波形数据送给数/模转换器作用的CODEC电路。

The correct rate of back substitution of discriminating is 100%. The contents of copper, iron and magnesium of other fruits such as Chinese goosebery and guava were put into the mathematic model, and the results indicated that the mathematic model is suitable for discriminate the nature of fruits.

得到数模为Y=-10.19173X_8~(-1)。42593X_5+0.14975X_4，即100 克水果可食部中X(8铜)、X5和X4的含量代入以上方程，如果函数值在温热性区间(-0.6423171，0.5275019)，则该水果属于温热性，如果函数值在寒凉性区间(-∞，-0.6423171)或(0.5275019，+∞)，则该水果属于寒凉性。

The transformation between digital signal and DC voltage was made with D/A converser and high voltage amplifier; varactor s were used for tuning components; the bandpass filter was a combline microstrip line one, its dimension was presented.

采用数模转换器和高压运放实现数字信号与直流电压的转换；以变容二极管作为调谐元件；带通滤波器采用梳状微带线结构，并给出了结构参数。

Using MK- 801 double board computer and digit to anolog interface circuit as hardwar, de-sign and a set of temperature autocortrol system , sassociating with DWK- 702 instrument of tempera-ture fine control, applying to production technique of T1 -superrconductors and making this automa-tize.

采用MK－801双板计算机及其数模接口电路为硬件，设计并制造一套温度自动控制系统，联合DWK－702精密温度控制装置，对T1系超导材料的烧制过程进行自动控制，使这一过程自动化、程序化、并提高了温度控制精度。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。