Two, the technical specifications of the DC power supply 

 The technical specifications of the DC power supply is divided into two: one is the performance index, including allowing the input voltage, output voltage, output current and output voltage adjustment range; another is the quality indicators used to measure the degree of stability of the output DC voltage. regulator factor (or voltage regulation), the output resistance (or current regulation), the ripple voltage (around random drift) and the temperature coefficient. 
 (1) The ripple voltage: AC voltage component superimposed on the output voltage. Oscilloscope observed peak to peak endoscopic sanitary pump is generally the millivolt range. Can also be used AC millivoltmeter to measure the RMS, but the ripple is not a sine wave, so there is some error, the general DC power supply ripple voltage VP-P ≤ 10mV. 

 (2) Voltage Regulation: Input voltage relative change of ± 10% of the output voltage relative change of the regulator factor and voltage regulation rate changes in the input voltage of the output voltage, so just to test one of them can be . 
 Output resistance and the amplifier output resistance of the same value when the input voltage is constant, produces an output voltage and output current change in the ratio of the absolute value of the current regulation: output current change from 0 to the maximum output voltage relative changes in value. Output resistance and current adjustment rate of change of load current on the output voltage, and therefore only need to test one of them can. 
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