Inductive-load clamp and release
Winding-resistance-aware current decay with a freewheel diode, rail-referenced TVS or drain clamp.
Development preview. Check the assumptions below before relying on a result. Calculations run in your browser.
How it calculates
Assumptions
- Clamp voltage and winding resistance are constant. Set clamp magnitude to the diode drop for a simple freewheel diode.
- Drain clamp includes continuing supply energy during decay; winding-referenced clamps do not. Avalanche/EAS ratings must be derated for temperature and repetition.
Worked example
These are the calculator's default inputs. Change any input above to recalculate.
Inputs
- Clamp connection
- drain
- Supply voltage
- 24 V
- Load inductance
- 0.05 H
- Initial current
- 2 A
- Winding resistance
- 5 Ω
- Clamp magnitude (per selected connection)
- 48 V
- Release current fraction
- 0.05
- Release repetition rate
- 1 Hz
- Allowed clamp single-pulse energy
- 0.2 J
Results
- Time to selected release current
- 0.00327687 s
- Switch voltage during clamp
- 48 V
- Time to zero current
- 0.00348307 s
- Initial inductor energy
- 0.1 J
- Clamp absorbed energy
- 0.157501 J
- Average clamp power
- 0.157501 W