Abstract:
A system for testing a DC power supply performance includes a comparison module, a judge module, and an alarm module. The comparison module receives DC voltage signals from the DC power supply, compares the DC voltage signals with a reference voltage respectively, and outputs a voltage level signal when the DC power supply is normal. The judge module receives the voltage level signal, and outputs a control signal according to the voltage level signal. The alarm module receives the control signal, and indicates status of the DC power supply according to the control signal.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to testing systems, and particularly to a system for testing power supply performance 
         [0003]    2. Description of Related Art 
         [0004]    Most electronic apparatuses are not equipped with internal power supply devices in order to save space and costs. Therefore, these electronic apparatuses require external power supplies. Computers are powered by power supplies, which are capable of converting alternating current into direct current. Testing power supplies over or under voltages is an important test for determining reliability. The reliability of power supplies is measured by comparing the input and output voltages of the power supplies and by measuring the output voltages of the power supply to test if they are within allowable limits. However, the above testing method needs a special test apparatus to test the power supply, which increases the testing cost. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]    Many aspects of the embodiments can be better understood with references to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views. 
           [0006]      FIG. 1  is a block view of an embodiment of a system for testing power supply performance. 
           [0007]      FIG. 2  is a schematic view of the system of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one. 
         [0009]    In general, the word “module,” as used herein, refers to logic embodied in hardware or firmware, or to a collection of software instructions, written in a programming language, such as, for example, Java, C, or Assembly. One or more software instructions in the modules may be embedded in firmware, such as an EPROM. It will be appreciated that modules may comprise connected logic units, such as gates and flip-flops, and may comprise programmable units, such as programmable gate arrays or processors. The modules described herein may be implemented as either software and/or hardware modules and may be stored in any type of computer-readable medium or other computer storage device. 
         [0010]    Referring to  FIG. 1 , a system in an embodiment for testing power supply performance includes a DC power supply  100 , a comparison module  200 , a judge module  300 , an alarm module  400 , a load module  500 , a switch module  600 , and an indication module  700 . The DC power supply  100  includes a plurality of output terminals for outputting +5VSB (standby voltage of +5V), +5V, +3.3V, +12V, −12V, PS-ON (Power Supply On) and PG (Power Good) voltage signals. 
         [0011]    Referring to  FIG. 2 , the comparison module  200  includes comparators A 1 ˜A 8  and resistors R 1 ˜R 13 . A non-inverting input terminal of the comparator A 1  and an inverting input terminal of the comparator A 2  receive a reference voltage respectively. An inverting input terminal of the comparator A 1  is grounded via the resistor R 3 . A non-inverting input terminal of the comparator A 2  is electrically coupled to the +12V voltage output terminal via the resistor R 1 . The resistor R 2  is electrically coupled between the inverting input terminal of the comparator A 1  and the non-inverting input terminal of the comparator A 2 . A non-inverting input terminal of the comparator A 3  and an inverting input terminal of the comparator A 4  receive the reference voltage respectively. An inverting input terminal of the comparator A 3  is grounded via the resistor R 6 . A non-inverting input terminal of the comparator A 4  is electrically coupled to the +5V voltage output terminal via the resistor R 4 . The resistor R 5  is electrically coupled between the inverting input terminal of the comparator A 3  and the non-inverting input terminal of the comparator A 4 . 
         [0012]    A non-inverting input terminal of the comparator A 5  and an inverting input terminal of the comparator A 6  receive the reference voltage respectively. An inverting input terminal of the comparator A 5  is grounded via the resistor R 9 . A non-inverting input terminal of the comparator A 6  is electrically coupled to the +3.3V voltage output terminal via the resistor R 7 . The resistor R 8  is electrically coupled between the inverting input terminal of the comparator A 5  and the non-inverting input terminal of the comparator A 6 . An inverting input terminal of the comparator A 7  and an inverting input terminal of the comparator A 8  receive the reference voltage respectively. The non-inverting input terminal of the comparator A 7  is electrically coupled to the PG voltage output terminal via the resistor R 12 . The non-inverting input terminal of the comparator A 7  is grounded via the resistor R 13 . The non-inverting input terminal of the comparator A 8  is electrically coupled to the +5VSB voltage output terminal via the resistor R 10 . The non-inverting input terminal of the comparator A 8  is grounded via the resistor R 11 . In one embodiment, the reference voltage is 2.55 volts. 
         [0013]    The judge module  300  includes a NAND element U 1  having input ports P 2 ˜P 9  and output ports P 1  and P 10 . Output terminals of the comparators A 1 ˜A 8  are electrically coupled to the input ports P 2 ˜P 9 . The alarm module  400  includes a transistor T 1 , a buzzer LS 1 , and a resistor R 14 . A base of the transistor T 1  is electrically coupled to the output port P 1  via the resistor R 14 . An emitter of the transistor T 1  is electrically coupled to the +5VSB voltage output terminal via the buzzer LS 1 . A collector of the transistor T 1  is grounded. In one embodiment, the NAND element U 1  is a CD4068 type NAND. The transistor T 1  is a PNP type transistor. 
         [0014]    The load module  500  includes multiple switches S 1 ˜S 3 , a fan F 1 , and resistors R 15 ˜R 25 . The +5VSB, −12V, +3.3V, +5V, and +12V voltage output terminals are grounded via the resistors R 15 ˜R 17 , R 20 , and R 23  respectively. The +3.3V voltage output terminal is electrically coupled to a first terminal of the multiple switch S 1 . A second terminal of the multiple switch S 1  and a third terminal of the multiple switch S 1  are grounded via the resistors R 18  and R 19 . The +5V voltage output terminal is electrically coupled to a first terminal of the multiple switch S 2 . A second terminal of the multiple switch S 2  and a third terminal of the multiple switch S 2  are grounded via the resistors R 21  and R 22 . The +12V voltage output terminal is electrically coupled to a first terminal of the multiple switch S 3 . A second terminal of the multiple switch S 3  and a third terminal of the multiple switch S 3  are grounded via the resistors R 24  and R 25 . The +12V voltage output terminal is also grounded via the fan F 1  to drive the fan F 1  rotating and dissipating heat for the load module  500 . 
         [0015]    The switch module  600  includes a press stopper S 4 , a Zener diode ZD 1 , and a resistor R 26 . The +5VSB voltage output terminal is electrically coupled to a cathode of the 
         [0016]    Zener diode ZD 1  via the resistor R 26 . The PS-ON voltage output terminal is electrically coupled to an anode of the Zener diode ZD 1  via the press stopper S 4 . The anode of the Zener diode ZD 1  is grounded. A connection point between the cathode of the Zener diode ZD 1  and the resistor R 26  outputs the reference voltage. The indication module  700  includes LEDs D 1 ˜D 8  and resistors R 27 ˜R 34 . The output terminals of the comparators A 1 ˜A 8  are grounded via the LEDs D 1 ˜D 8  respectively. The output terminals of the comparators A 1 ˜A 8  are also electrically coupled to the +5VSB voltage output terminal via the resistors R 27 ˜R 34  respectively. 
         [0017]    During a test, the DC power supply  100  is electrically coupled to the test system as shown in  FIG. 2 . The press stopper S 4  is pressed once, and then it is released. The PS-ON voltage signal is output. Then +5VSB, +5V, +3.3V, +12V, −12V, and PG voltage signals are output. When the voltage output terminals output normal voltage signals, the output terminals of the comparators A 1 ˜A 8  output high voltage levels. The high voltage levels are received by the judge module  300 . The judge module  300  also outputs a high voltage level. The alarm module  400  receives the high voltage level and the transistor T 1  turns off. The buzzer LS 1  does not buzz, and the LEDs D 1 ˜D 8  emit light to indicate the DC power supply  100  is normal. If a certain voltage output terminal, for example the +12V voltage output terminal outputs an over voltage signal. The output terminal of the comparator A 1  outputs a low voltage level, and the output terminal of the comparator A 2  outputs a high voltage level. The judge module  300  outputs a low voltage level. The alarm module  400  receives the low voltage level and the transistor T 1  turns on. The buzzer LS 1  buzzes to indicate the DC power supply  100  is abnormal. The LED D 1  does not emit light to indicate the +12V voltage output terminal outputs an over voltage signal. 
         [0018]    If a certain voltage output terminal, for example the +12V voltage output terminal outputs an under voltage signal. The output terminal of the comparator A 1  outputs a high voltage level, and the output terminal of the comparator A 2  outputs a low voltage level. The judge module  300  outputs a low voltage level. The alarm module  400  receives the low voltage level and the transistor T 1  turns on. The buzzer LS 1  buzzes to indicate the DC power supply  100  is abnormal. The LED D 2  does not emit light indicating the +12V voltage output terminal outputs an under voltage signal. 
         [0019]    It is to be understood, however, that even though numerous characteristics and advantages of the embodiments have been set forth in the foregoing description, together with details of the structure and function of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.