Chroma ATE Inc.

2013
2013
Chroma Model 63600 series Electronic Load – Arbitrary Loading Current Waveform
2013/09/04

In the field of power supply testing, the electronic load provides all types of testing mode. It is an essential testing equipment. In a power supply transient response test, test modes which use the electronic load for testing include: 1.Dynamic Mode 2.Program Mode 3.External Waveform Control.

Chroma 63600 Series Electronic Load has built-in a new mode – the User Defined Waveform (UDW).

User Defined Waveform (UDW)

The 63600 Series offers the brand-new UDW function, real current waveforms are recorded through the oscilloscope and saved in the memory of the 63600 Series Electronic Load to carry out real current simulation. In addition, users can use Excel to edit the current waveform that will be loaded to 63600 series loads. Operation is simple as shown in figure 1.

Figure 1 UDW Function Device
Figure 1 UDW Function Device

The UDW function has the following advantages::

    1. Simulate real current waveform
    2. Testing the response of the power supply under real application
    3. Wide bandwidth, fast response
    4. Easy setting and operating
    5. 10 sets of user defined current waveform, each set able to edit 120,000 current levels
    6. Able to chain 10 sets of user defined current waveform, maximum 1.2M current levels
    7. Parallel up to 5 modules
    8. Maximum loading current 400A, maximum power 2,000W
    9. No external DAQ card needed
    10. No external waveform generator needed
    11. Suits RD, QA, production line to carry out power supply verification and testing

Many power supplies have been strictly tested before being shipped. For example: the Load Regulation test is usually carried out in the dynamic current mode, but after all it is still a change between 2 loading levels (figure 2). Therefore, when an inrush current occurs between 2 loading levels, it is afraid that users cannot test whether the power supply can function normally.

Figure 2 Dynamic Current Waveform
Figure 2 Dynamic Current Waveform


To resolve the issues, using the program function of the E-load to edit multi-level loading currents (figure 3) to carry out load regulation test of the power supplies. However, it is a complex process to edit the multi-level loading currents, and the programmability of loads are usually less than 200 levels. When customers require more loading levels or more complex loading currents, the program function cannot satisfy customers’ requirements.

Figure 3 Multi-level Loading Currents Waveform
Figure 3 Multi-level Loading Currents Waveform


Some E-loads offer the external signal control function to carry out current simulation, but the function is limited by the bandwidth of the E-load which in turn causes a distortion of the current waveform.

Therefore, the UDW function of the 63600 series can simulate even more levels and more complex current waveforms (figure 4) up to a maximum of 1.2M current levels. Through the real loading current test, users can confirm the power supplies are operational under actual loading conditions to achieve a more realistic verification instead of an approximate loading current.

Figure 4 Multi-level Loading Currents Waveform
Figure 4 Multi-level Loading Currents Waveform


As shown in figure 4, the area of the blue circle indicates the turn on current of the power supplies. The power supplies need to be verified to make sure they are capable of outputting the surge current. The area of the red circle indicates the surge current which may cause the voltage of the power supplies to be unstable. The worst case will cause the power supplies to shutdown.

The real current waveform in figure 5 is captured by the oscilloscope when the power supply offers the current to the mother board. Figure 6 shows the captured waveform data in figure 5 being saved to the 63600 series and the duplicated the real loading current waveform by the E-load.

Figure 5 Current Waveform Captured by Oscilloscope
Figure 5 Current Waveform Captured by Oscilloscope


Figure 6 UDW Restores Real Current Waveform
Figure 6 UDW Restores Real Current Waveform

Besides, for single-channel high output power supply above 400W, for example, server power carries out the multi-level current dynamic test (figure 3) or turn on loading current simulation (figure 6), the UDW provides synchronized dynamic function. Users are able to perform the sync. dynamic test by using the UDW function with a maximum loading power of 2,000W. For multi-channel output power supply, for example, SMPS and printer power, the strictest test is the sync. dynamic test involving all channels at once. The UDW function can also support this test.

The advanced UDW function will offer users a faster and more convenient experience. It makes power supply testing and verification no longer a boring job. Please contact us immediately to experience the all new UDW function.

Model 63600 series Programmable DC Electronic Loadhttp://www.chromaate.com/product/63600_series_Programmable_DC_Electronic_Load.htm