Notes / Test & Debug Instruments
Power supply and electronic load
Protect the board with a current limit and test the power section with an electronic load. The equipment that makes the first power-up safe.
Variable power supply (bench supply)
You set the voltage and the current limit together. When the set current is reached, it lowers the voltage to hold the current there (CC mode).
- For the first power-up of a new board, set the limit a little above the expected consumption. If there is a short, the voltage drops sharply and the CC indicator lights, so you know at once.
- Motor tests have large momentary currents, and behaviour turns strange when the current limit is hit. Do not just raise the limit; look for the cause first.
- When a motor decelerates and sends energy back (regeneration), the output voltage of an ordinary supply can rise. Use a battery or equipment that can absorb regeneration.
Electronic load
An instrument that draws a set amount of current.
| Mode | Use |
|---|---|
| CC (constant current) | Testing a converter's maximum current |
| CR (constant resistance) | Imitating a real resistive load |
| Dynamic | Changing the load quickly to check the output voltage response |
| Battery discharge | Measuring capacity |
Order for verifying a power section
No-load voltage → voltage and efficiency at rated load → response to load steps (with an oscilloscope) → long-term heating (thermal camera). Only after going through this sequence can the power section be trusted.