FARES PCB FARES Industrial Products Bipolar Stepper Driver General Description Driving stepper motor is common necessity in most robotic projects. A stepper motor is a brushless, synchronous electric motor that can drive a full rotation into a large number of steps. Stepper motor is ideally suited for precision control. This motor can operate in forward/reverse with controllable speed from a microcontroller through a driver circuit. There are various kinds of stepper motor. Some example are variable reluctant stepper motor, permanent magnet stepper motor, bipolar/unipolar stepper motor, bifilar stepper motor and hybrid stepper motor. step motor driver is a step and direction driver with microstep capability. can drive up to 3.5 ampere per phase with 4 level selected phase current from 20% to 100% via DIP switch. Full-step, half-step, micro-step resolution is also switch selectable. One of the most important features of the driver is controlling the holding current as a percent of the nominal operating current to overcome excessive motor and driver heating. This drive is compatible with any micro-based control system or any breakout board. Figure 1. Driver Board 2012 FARESPCB Corporation Page 1 of 12
Features DC12-36V single power input Maximum 3.5 Amps/phase motor output. Step, direction, Enable input TTL compatible control signals (10mA). Resolution 1,1/2,1/8,1/16 micro stepping output 4 adjustable work current levels 20%, 50%, 75%, 100% of the maximum nominal current. Automatic 4 selectable levels for idle current reduction. (20%, 50%, 75%, 100% holding current of work operating current). All controlling inputs are opto isolated for safety. High-speed isolate optical coupler on step and direction inputs. Inputs are brought out via pin header and screw clamp connector for flexibility. LED indicator for Power input Red LED. Direction input Green LED. Enable input Green LED. Step input Green LED. Fault output Red LED. Work/hold current state Yellow LED. Embedded test mode for testing driver without needing of external control signals. 30 u sec minimum width for CLK input pulse. Dimension: 150 x 115 x 50 mm including fan and heatsink. 2013 FARESPCB Corporation Page 2 of 12
Figure 2. System Overview Microcontroller Breakout board MOTOR Single motor control system diagram X Control MOTOR X Breakout board Y Control MOTOR Y Z Control MOTOR Z Three axes motor control system diagram 2013 FARESPCB Corporation Page 3 of 12
Bipolar Stepper Motor Driver Signal Input Pins Function Description Table1. Connector signal definition Definitio Label Function n 5V External supply voltage External supply power for optocouplers. Input to drive the stepper motor. This pin is TTL/CMOS logic (5V and 0V). Each pulse (logic change from 0 to 1) will drive Stepping the stepper motor one step. This CLK input pulse input must be LOW in the idle state to ensure that autoswitching to hold current work properly. Minimum Pulse time is 30uSec. Input for stepper motor to rotate Stepper CW (clockwise) or CCW driver (counterclockwise). This pin is DIR rotation TTL/CMOS logic (5V and 0V). direction The direction is depends on the input connection sequence of stepper motor Input pin to enable. This pin is TTL/CMOS logic (5V and 0V). Stepper 0V input will enable the motor driver driver further hold the shaft of ENA enable stepper motor while 5V will input disable the motor driver and release the shaft of the stepper motor. By default, the driver is disabled. Motor Motor coil 1 W1 winding 1 Motor Motor coil 2 W2 winding 2 External power supply from Motor 12V to 36V for both motor 12-36V supply power and control circuit voltage biasing. 2013 FARESPCB Corporation Page 4 of 12
LED Indicators Description Table2. LED indicators definition LED Color Function DIR EN Step Fault W/H POWER Green Green Green Red Yellow Red This LED toggles its state when motor direction is reversed. This LED turns on when driver is enabled. I.e. when Enable input is low. This LED turn on when CLK input is active. I.e. when CLK input is low. This LED is indication for excessive increasing in temperature. In normal operation (work current) this LED is turned on. If the driver switched to hold current this LED is turned off. This is Power indicator LED for 12-36V input. 2013 FARESPCB Corporation Page 5 of 12
Bipolar Stepper Motor Driver Resolution Adjustment Table3. Mode DIP switch setting Mode DIP switch 1 2 Step Comment Full Step Half Step 1/8 Step 1/16 Step 200 Pulse per turn 400 Pulse per turn 1600 Pulse per turn 3200 Pulse per turn Work Current Setting Table4. Work current DIP switch setting Current DIP switch 3 4 2013 FARESPCB Corporation Work Current Percentage Absolute 100% 75% 50% 20% 3.5 Ampere 2.5 Ampere 1.75 Ampere 0.7 Ampere Page 6 of 12
Stepper motor doesn t necessary require the work operating current during idle state where driver is enabled but no pulses produced. produces a very useful way to reduce the holding current (idle current) automatically to one of four percentage of the nominal operating current (20%, 50%, 75% or 100%).so it saves power consumption and reduces heating of driver and motor. Hold Current Setting Table5. Hold current DIP switch setting Current DIP switch 1 2 Hold Current 100% of work current 75% of work current 50% of work current 20% of work current Note: 1. If the hold current setting is greater than the work current, the holding current will be equal to the working current. 2. To ensure that the automatic switching to hold current will work properly, the idle state (inactive state) of the CLK input must be Low. I.e. CLK input must be energized during absence of pulses. 2013 FARESPCB Corporation Page 7 of 12
Test Mode can be tested without any external control signals. Just set Test mode pin to on state and connect power to driver. Caution: Never connect any external control signals before setting Test switch to state. This my cause permanent damage of driver. Test mode sequence is: One turn in one direction with 2500 µsec interval between pulses, then wait about 500 msec and resume another turn in the opposite direction with 2500 µsec interval between pulses. Test mode is auto-detecting the microstep resolution and recalculate the required number of pulses per turn. 2013 FARESPCB Corporation Page 8 of 12
Wiring Diagram may drive 4, 6 or 8 lead stepper motors. Some motor wiring provides high torque and some other provides high speed. Figures1-4 shows many motors types and its connections to obtain high torque and speed. Figure 3. Four leads motor connection Figure 4. Six leads motor (High torque connection) 2013 FARESPCB Corporation Page 9 of 12
Figure 5. Six leads motor (High speed connection) Figure 6. Eight leads motor (High torque connection) 2013 FARESPCB Corporation Page 10 of 12
Figure 7. Eight leads motor (High speed connection) Typical Control System Connection +5V 4 5V CLK DIR EN 1 2 3 4 1 2 3 Microcontroller System 5 If the microcontroller can sink 10mA current or more, there s no need for any external transistors. Just connect microcontroller output directly to driver. Caution: Don t connect or disconnect the motor while the driver is energized. This may cause permanent damage to the Driver. 2013 FARESPCB Corporation Page 11 of 12
Notes: Copyright 2013 by FARESPCB For our full range of products see our website at http://www.farespcb.com If you have any technical questions about our products, e-mail us at www.support@farespcb.com FARESPCB co. (Headquarters) 17 Yossif elgendy st. Bab ellouq, Tahreer, Cairo Egypt. Tel: 02-23904484 Mob: 01000652977 FARESPCB Co reserves the right to make changes in circuit design, software and/or specifications at any time without prior notification. For the most up-to-date information, please visit our web site at http://www.farespcb.com Information furnished by FARESPCB is believed to be accurate and reliable. However, FARESPCB assumes no responsibility arising from the use of the specifications described. Warrantee: FARESPCB warrants its products against defects in materials and workmanship for a period of 30 days. If you discover a defect, we will, at our option, repair or replace your product or refund your purchase price. This warrantee does not cover products that have been physically abused or misused in any way. Our Distributor: RAM Electronics 32 El Falaky St. Bab El Louk Tahreer, Cairo Egypt. Tel: 02-27960551 www.ram.com.eg Sales@ram-electronics.com 2013 FARESPCB Corporation Page 12 of 12