HSI Stepper Motor Drivers

HSI, a leader in linear and rotary stepping motors, also provides Unipolar/Bipolar L/R (Part No. 39105) and Bipolar Chopper Drives (Part No. 40105).

The unipolar/bipolar L/R (Part No. 39105) drive circuit is able to run both unipolar or bipolar stepping motors. The unipolar motor has 6 leads (center-tapped coils). This type of arrangement is electronically simple to operate. However, as compared to the bipolar motor, performance is reduced to 70% since only half of the copper is used at any one time. The bipolar motor has 4 leads and gets maximum performance. This arrangement, however, requires reversing the current in each motor phase which makes the electronics a little more elaborate.

Part No. 39105 drives are available from stock and are ideal for the initial as well as production phases of your project. HSI motors will deliver rated performances when controlled by these drivers.

Driver No. 39105 Technical Data

• Size: 3.0" x 3.5" x 1.5" (7.6 cm x 8.9 cm x 3.81 cm)
• Power Requirement: +7.5 VDC to +32 VDC
• Unipolar Peak rating: 1.5A/ø
• Bipolar Peak rating: 3.0A/ ø
• Motor Speed Control: Variable, 10 to 2000 steps per sec.

Driver No. 39105 Unipolar/Bipolar Features

• Enable/disable control (on board/remote)
• Direction control (on board/remote)
• Single step
• Full step (2 phase on)
• Full step wave (1 phase on) (N/A in Bipolar)
• Half step (N/A in Bipolar)
• Step inhibit

Bipolar L/R Drive

Drives a four wire stepping motor. This technique commutates current through 100% of the coil turns resulting in the best motor performance. The overall efficiency of the configuration is quite high.

Unipolar L/R Drive

Requires a motor with center-tapped coils. This type of arrangement is simple and electrically efficient with regard to electronics. In this configuration current only flows through 50% of the coil turns, at any time. This and other coil winding factors reduces holding torque to about 70% of that obtainable in an equivalent bipolar configuration.

Bipolar Chopper Drive

A chopper drive is a power-efficient method of current driving a stepping motor to obtain higher stepping rates. Torque, likewise, is maintained which otherwise would have diminished due to the effects of counter E.M.F. and increased coil impedance.

HSI’s bipolar chopper drive (Part No. 40105) has been designed for easy set-up and use. Just connect a single power supply and a motor and its ready to run! Motor current is set using an on-board potentiometer. No external current setting resistors are required. This feature-packed drive provides all basic motor controls, including full or half stepping of bipolar steppers and direction control. An oscillator circuit is standard on the drive with an on-board speed control potentiometer. In addition, external input/output signals allow complete remote control of all drive functions.

Unipolar chopper drives are not generally recommended due to their lower inherent operating efficiency.

The average input power rating of the motor must be adhered to, otherwise overheating will result. It is permissible to operate at 2X rated current (4X power) utilizing a 25% duty cycle.

Driver No. 40105 Technical Data

• Size: 3.75" x 2.95" x 1.5" (9.53 cm x 7.49 cm x 3.81 cm)
• Power Requirement: Single unregulated power supply providing +24 VDC to +40 VDC
• Output Current: Fully adjustable from 66 mA/ ø to 3 A/ø
• Continuous rating: 2A/ø
• Peak, non-repetitive rating: 3A/ø
• Chopper Frequency: ~20 Khz
• Onboard Oscillating Range: <10 pulses/sec. to >2,000 pulses/sec.
• Stepping: Full step/Half step capability

Driver No. 40105 Features

• On board or external step pulse clock
• On board or external single step switch
• On board or external step rate control potentiometer
• On board or external direction control
• On board or external full step/half step control
• On board or external outputs enable control
• On board output current control potentiometer
• External home output
• External reset control
• External chopper synchronous output