哪位高手能帮我翻译一下,谢谢!

AstheREF(+)toREF(-)voltagedecreasestheincrementalvoltagestepsizedecreases.At5VoneLSBr... As the REF(+) to REF(-) voltage decreases the incremental voltage step size decreases. At 5V one LSB represents ~20 mV, but at 1V, one LSB represents ~4 mV.
As the reference voltage decreases, system noise will become more significant so greater precaution should be enforced at lower voltages to compensate for system noise; i.e., adequate supply and reference bypassing, and physical as well as electrical isolation of the inputs.
2.2 Absolute Analog Inputs
The ADC0808/ADC0809 may have been designed to easily utilize ratiometric transducers, but this does not preclude the use of non-ratiometric inputs. A second type of input is the absolute input. This is one which is independent of the reference. This implies that its absolute numerical voltage value is very critical, and to accurately measure this voltage the accuracy of the reference voltage becomes equally critical. The previous designs can be modified to accommodate absolute input signals by using a more accurate reference. InFigure 4 the power supply reference could be replaced by LM336-5.0 reference. R1 and R2 of Figure 6 , and R1 and R3 ofFigure 7 may have to be made more accurately equal. In some small systems it is possible to use the precision reference as the power supply as shown in Figure 7. An unregulated supply voltage l5V is required, but the LM336-5.0 functions as both a regulator and reference. The dropping resistor R must be chosen so that, for the whole range of supply currents needed by the system, the LM336-5.0 will stay in regulation. As in Figure 4 separate supply and reference traces should be used to maintain a noiseless supply. If the system requires more power, an op amp can be used as shown in Figure 8 to isolate the reference and boost the supply current capabilities. Here again, a single unregulated supply is required.
2.3 Differential Inputs
Differential measurements can be obtained by playing a little software trick. This simply involves sequentially converting two channels then subtracting the two results. For example, if the difference voltage between channel 1 and 2 is required, merely convert channel 1 and read the result. Then convert channel 2, input the result, and subtract it from the first result. (See Figure 9 .) When using this procedure, both input signals must be stable throughout both conversion times or the end result will be incorrect. One way to
get around this is to use two sample/holds which are sampled at the same time.
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作为档( + )档( - )电压降低电压增量步下跌. 在5v设有一个代表~20 mV时,但1V左右,其中设有代表2~4 mV之间. 作为参考电压下降, 系统噪音将变得更加重要,以防范更应该执行在低电压,以补偿系统噪音; 即,供应量充足,而且绕开参考,以及身体和电气隔离的投入. 2.2绝对模拟的投入adc0808/adc0809可能已经设计能轻易地利用2:1的传感器, 但这并不排除使用非2:1投入. 第二种意见是绝对的投入. 这是一个有独立的参考. 这意味着其绝对数值电压值是非常重要的, 并精确测量此电压精度的参考电压变得同样关键. 以前的设计,可改装,以容纳绝对输入信号用一个更准确的参考. 4 infigure供电范围可替代lm336 - 5.0参考. R1和R2图6 和R1和R3的7 offigure可能须作出更准确相等. 在一些小系统,有可能利用精密参考电源如图 7 . 不受供电电压l5v要求,但lm336 - 5.0职能,同时作为一种调节和参考. 下降的电阻住宅必须选择,使 提供一系列的电流供应所需要的制度, lm336 - 5.0会留在监管. 正如在图4单独供应和参考痕迹,应该是用来维持一个无声的供应. 如果系统需要更多的电力, OP的安培可以用如图8孤立的参考和刺激电流供应 能力. 再次,不受单一供应所需. 2.3投入微分差分测量可扮演一个小软件的伎俩. 这仅仅是按顺序把两个渠道,然后减去两个结果. 例如,如果电压差分之间的通道1和第2款规定, 仅仅转换频道1和阅读效果. 然后转换成2通道,输入结果,减掉它从第一的结果. (见图9 ) . 当使用这个程序, 两个输入信号必须是稳定整个两者转换的时候或最终结果将是错误的. 单程惟我独尊,这是用两个样本/持有所取样在同一时间
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