The LED constant voltage source to compare constant currently source
| Item | Constant voltage source | Constant currently source |
| Output voltage | permanent | Self-adjusting |
| Output currently | Self-adjusting | permanent |
| Output Power | permanent | Self-adjusting |
| Output of short-circuit protection | None | Yes |
| Output of overload protection | None | Yes |
| Application range | Incandescent lamp, quartz lamp, amplifier | LED, Fluorescent lamp, energy saving lamp |
| LED driving circuit and connection mode | Serial connect | Parallel connection |
| Total power efficiency (isolated) | 25%－68% | 59%－89% |
| Total power efficiency (NONE isolated) | 34%－72% | 79%－97% |