Driver circuit for a stepping motor

Electricity: motive power systems – Positional servo systems – With particular motor control system responsive to the...

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Details

318138, 318254, 318293, H02P 800, H02P 812, H02P 836

Patent

active

056569106

DESCRIPTION:

BRIEF SUMMARY
This invention relates to a driver circuit according to the preamble of claim 1. Such a driver circuit is known from EP 0 394 941 A2.


TECHNICAL FIELD

One embodiment of the invention relates to a driver circuit for a two-phase stepping motor having two motor windings each of which is supplied by a full bridge circuit, each full bridge circuit having a parallel connection, connected between the two poles of a power supply source, with two series-connected controllable driver elements in each case, and the corresponding motor winding being connected between the connection-point between the two driver elements of one series connection and the connection point of the two driver elements of the other series connection, and having a control logic circuit which is coupled on the output side with control inputs of the individual controllable driver elements and drives them to release winding current pulses for a half-step mode of the stepping motor in such a way that alternatingly only one motor winding, only the other motor winding or both motor windings are energized, or drives the control inputs of the individual controllable driver elements to release bipolar winding current pulses for a full-step mode of the stepping motor.
Such a driver circuit can also be controlled for full-step mode.


BACKGROUND OF THE INVENTION

A stepping motor is controlled by alternatingly energizing its windings. In the type known from EP 0 394 941 A2 FIG. 2 shows a typical control sequence for the half-step mode preferred for its quiet running for a two-phase stepping motor with two windings. FIG. 2(a) shows bipolar current pulse sequence IL1 for one winding. FIG. 2(b) shows bipolar current pulse sequence IL2 for the other winding. The armature position of the stepping motor resulting from this control sequence for half-step mode is indicated in FIG. 2(c).
The periodic change-over of the pulsed winding currents causes electromagnetic interference to occur both over the motor leads connected with a motor driver and over the supply voltage lines. These lines thereby act as antennas. By making the leads from the driver to the motor very short one can practically eliminate their antenna effect. However the supply voltage lines are relatively long and form very good antennas.
The driver circuit known from EP 0 394 941 A2 performs current regulation even during maximum current flow. This leads to a corresponding voltage drop on a regulating transistor. The consequence is a high power loss.
From DE 29 44 335 A1 it is known to supply the windings of a stepping motor with current pulses which are not digital but have a staircase form with four amplitude values. This makes it possible to increase the step number per revolution of the stepping motor. The resulting total current contains stages which lead to interference.
The driver circuit known from DE 29 44 335 A1 works in principle like the driver circuit in EP 0 394 941 A2 but uses a clocked regulation with pulse width modulation. Although this reduces losses, it increases the interference.
Known stepping motors include so-called chopping or clocked stepping motor drivers e.g. as in DE 29 44 335 A1, which subject the windings of the stepping motor to a series of pulses during each energizing phase, and non-chopping stepping motor drivers (e.g. as in EP 0 394 941 A2), which subject the individual windings to only one current pulse during each energizing phase.
With chopping stepping motor drivers, current regulation is effected by pulse width modulation of the voltage across the particular motor winding energized. With the switching frequencies of a few 10 kHz usual today, considerable electromagnetic interference occurs unless suitable blocking measures are taken. A relevant part of the total design effort and financial expense for a stepping motor system with such current regulation is required for these blocking measures. A typical integrated stepping motor driver with chopping current regulation is PBL 3717 from SGS-Thomson, shown in the corresponding data sheet.
With non-chopping st

REFERENCES:
patent: 4167693 (1979-09-01), Liska et al.
patent: 4562387 (1985-12-01), Lehnhoff
patent: 4568867 (1986-02-01), Remus et al.
patent: 4626760 (1986-12-01), Bui et al.
patent: 4675590 (1987-06-01), Pellegrino et al.
patent: 4682092 (1987-07-01), Pellegrino et al.
patent: 4710686 (1987-12-01), Guzik
patent: 4780651 (1988-10-01), Nakano et al.
patent: 4818924 (1989-04-01), Burney
patent: 4845417 (1989-07-01), Ohkubo et al.
patent: 4862051 (1989-08-01), Moteki
patent: 4985666 (1991-01-01), Nakabayashi
patent: 5032780 (1991-07-01), Hopkins
patent: 5144209 (1992-09-01), Ingji et al.
patent: 5163172 (1992-11-01), Hakala
patent: 5164649 (1992-11-01), Sarbach et al.
patent: 5182499 (1993-01-01), Inaji et al.
patent: 5237254 (1993-08-01), Guerin
patent: 5319291 (1994-06-01), Remirez
patent: 5530332 (1996-06-01), Rees
SGS-Thomson data sheet PBL3717A, pp. 643-652.
Motorola data sheet MC33192, Motorola Inc. Rev. 2.0 Mar. 92, pp. 1-9.

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