Stall detection circuit and method
US6900657B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 24, 2003 |
| Grant date | May 31, 2005 |
| Priority date | — |
| Expiry date | Nov 28, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P8/36
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A stall detection circuit and method for a stepper motor. The circuit has an H-bridge configuration with an additional circuit pathway to ground being connected at a point between two center windings. During the transition between step sequences, the circuit employs a monitoring phase in which the previously active low side driver is turned off such that current passes through only the first winding and then is diverted to ground via the additional pathway. While the phase voltage is thus momentarily extinguished, the second coil is used to monitor the motor's back EMF, from which it can be determined whether the rotor is in a normal running mode, a stall, or a reverse condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.