Agilent AN 372-1 - Manuals - manualsarea.com

Page 2 - An Overview of Power Supply Topologies; Introduction; Table 1

2 As regulated-power supply technology evolves, testing methods for design verification and productfunction require more sophisticated electronic equip-ment. The different power supply architecturesand output combinations also dictate the need forversatile test instruments that can accommodate abroa...

Page 3 - Power Supply Testing Instrumentation; An Overview of Power Supply Testing Needs

3 Power supplies are used in a wide variety of prod-ucts and test systems. As a result, the tests per-formed to determine operating specifications candiffer from manufacturer to manufacturer, or fromend user to end user. For instance, the tests per-formed in an R&D environment are primarily forp...

Page 4 - Load Transient Recovery Time; Power Supply Tests; Table 2; Figure 1. Load Transient Recovery Time

4 Load Transient Recovery Time A constant voltage DC power supply is designedwith a feedback loop which continuously acts tomaintain the output voltage at a steady-state level.The feedback loop has a finite bandwidth, whichlimits the ability of the power supply to respond to a change in the load cur...

Page 5 - Test Overview/Procedures; of the power supply can be made with; Figure 2. Load Transient Recovery Test Configuration and V; Measurement Results for a CV Power Supply

5 For a step change in load current, a marginally stable CV power supply will have a ringing voltageoutput. This defeats the purpose of the power sup-ply’s regulation circuitry and can be damaging to voltage-sensitive loads. An example of a voltage-sensitive load is the logic circuitry in a computer...

Page 6 - should not exceed the; Figure 4. Load Effect Testing Configuration; only with respect to load current changes.

6 Load Effect (Load Regulation) Load Effect or Load Regulation is a static perform-ance measurement which defines the ability of apower supply under test to remain within specifiedoutput limits for a predetermined load change (seeFigure 3). In a CV power supply, the inf luencedquantity of interest i...

Page 7 - Current Limit Characterization; Test Overview/ Procedures

7 Current Limit Characterization Current limit measurements demonstrate the degreeto which a constant voltage power supply limits itsmaximum output current to a preset value. Thispreset value can be fixed or variable throughout aspecified range. There are basically three types ofcurrent limiting des...

Page 10 - Efficiency

10 Efficiency The efficiency of a power supply is simply the ratio of its total output power to its total inputpower. To obtain the true input power (rms voltage x in-phase rms current) of a typical AC-to-DC converting power supply, commercially availablewattmeters or AC sources can be used to measu...

Page 11 - Figure 11. Start-Up Delay Test Configurations and Results

11 To fully characterize the start-up sequence of thepower supply under test, measurements must bemade of the output voltage response to the instan-taneous application of the AC input (see Figure 11).A digital oscilloscope should be used so that stor-age of the output values can be accomplished fort...

Page 12 - Other Power Supply Tests

12 An observation of any DC power supply data sheetfrom a power supply manufacturer reveals a numberof design specifications that must be verified andtested. These tests often differ in technique and inthe test equipment that is used to measure the var-ious parameters. The common aspect of all of th...

Page 13 - Power Supply Testing with Agilent Electronic Loads

13 The Agilent Electronic Load Family offers the powersupply tester the solution for many of the tests thatmust be performed. For bench or system applica-tions in large or small scale testing environments,Agilent Electronic Loads provide high quality andreliability with superior performance, feature...