Download OMD23-2 Micro

OMD23-2
Micro-Step Driver
USERS MANUAL
OMD23-2 USERS GUIDE
REVISION HISTORY
Revision
A
Date
Description
8/19/2011
Initial Release
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OMD23-2 USERS MANUAL
Overview ....................................................................................................................................................... 4
Included: ........................................................................................................................................................ 4
Pinout ............................................................................................................................................................ 5
Installation ..................................................................................................................................................... 5
Power Supply ................................................................................................................................................ 7
Stepping Motors ............................................................................................................................................ 8
DIP Switch (JP1) Location ............................................................................................................................ 9
Setting the Output Current (JP1) .................................................................................................................. 9
Microstep Resolution (JP1) ......................................................................................................................... 10
Control Input ................................................................................................................................................ 10
Electrical Specifications .............................................................................................................................. 11
Thermal Specifications ................................................................................................................................ 11
Dimensions & Mounting .............................................................................................................................. 12
Design Tips ................................................................................................................................................. 12
Optional Heat Sync Mount .......................................................................................................................... 13
APPENDIX………………..…………………………………………………………………………………………14
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OMD23-2 USERS GUIDE
Overview
The OMD23-2, one of Pro-Dex/OMS latest developments, represents a very compact drive that can be
mounted easily in many applications.
OMD23-2 Features:
• Single 12V – 40V input supply voltage range
• 0.0 to 2A phase current adjustable via DIP switches
• Full, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, 1/128, 1/256 step set by DIP switch
• Electrically isolated and optically coupled STEP, DIR & ENABLE inputs
• Control input voltage: 5-20V default
• Easy wire-up using the screw terminal connectors included with the drive
• No heat sink required under 1Amp
Included in the Box:
Mating Connector:
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OMD23-2 USERS MANUAL
Pinout
The following picture shows the pins for connecting to the OMD23-2 board:
Installation
The following installation procedure outlines the minimum steps required to make the OMD23-2
operational:
1. Connect a 12VDC to 40VDC power supply to connector J1 (see diagram). Pin 1 needs to be
connected to Ground and Pin 2 to the positive voltage (VSUPPLY). The power supply must be capable
of providing 2A of current depending on the supply voltage and current settings that you are planning
to use. See section “Power Supply”.
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OMD23-2 USERS GUIDE
2. With the power “Off” connect a motor to pins 3,4,5,and 6 of J1 (see diagram). Typical motor
connection diagrams are shown in the “Stepping Motors” section of this manual. Be sure to insulate all
motor leads and unused leads (6 lead motor) to prevent shorts to ground or to each other.
3. Set the appropriate current value using the DIP Switches (JP1). See Section “Current Settings” for
more information.
4. Wire in your step, direction, and driver enable signals as well as the positive reference voltage level
of the signals (VIN+) to connector J1. See section “Control Input” of this manual for more details.
5. Set the resolution as desired using the DIP switches. See Section “Microstep Resolution” for more
information.
6. Apply power to the OMD23-2.
“Do’s, Don’ts and Important Notes”
Do not connect or disconnect the motor when power is “ON.“
The module case is tied to the logic common and power pins internally. Do not tie your power supply
to ground at another location.
The power supply voltage, including ripple and line voltage fluctuations must not exceed 40Vdc or
be less than 12Vdc.
Make sure the motor to be used is compatible with the drive.
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OMD23-2 USERS MANUAL
Power Supply
The OMD23-2 is powered from a single unregulated DC power supply. The power supply is connected
via pins 1 and 2 of the J1 Connector. The input voltage must be in the range of 12VDC to 40VDC.
Pin
1
2
Function
Ground
High voltage
Recommended Power Supply Circuit
In general, unregulated DC (or linear regulated) power supplies are best suited for stepper motor
applications. Switching power supplies, which tend to be very cost efficient, are also suited for many
stepper motor applications. However, their ability to provide surge currents is limited and may require
additional capacitors to be added depending on your application.
A single power supply can be used for single axis configurations, or multiple axes, provided
component values are scaled accordingly. Alternatively, individual axes can be supported by individual
power supplies.
If multiple drivers are used with one power supply, each drive should have separate power and ground
wires that connect directly to the output capacitor of the power supply.
“Do’s, Don’ts and Important Notes”
Individual axes should be independently fused for fault isolation.
The power supply voltage, including ripple and line voltage fluctuations must not exceed the peak
rating of 40Vdc or be less than 12Vdc.
Do not connect or disconnect motor wires while power is applied.
Wire size used to connect the power source to the driver should be at least 18 gauge. Heavier wire
should be used for longer distances between the power supply and the driver.
The power supply output current needed is dependent on the supply voltage, motor selection and
load.
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OMD23-2 USERS GUIDE
Stepping Motors
The OMD23-2 is a bi-polar, chopper driver that works with both bi-polar and uni-polar motors, i.e. 8, 4
and 6 lead motors. It is also possible to half a 6 lead center tapped motor with the OMD23-2, however
the performance may be compromised. To avoid unstable chopping conditions and to provide a higher
speed-performance ratio, a motor with a low winding inductance is preferred.
Drive Current
The ideal current for a given motor is based on the specific characteristics of the motor and the
requirements of the application. As a result, establishing the correct current is often determined
empirically. Insufficient current will result in inadequate torque and under utilization of the motor.
Excessive current can cause high-speed torque ripple, resulting in stalling or pole slippage, over
heating of the motor and general inefficiency of the system. Current setting procedures are described in
the next section; “Setting The Output Current”
Connecting a Stepping Motor (J1 pins 3-6)
Pin #
Description
Function
3, 4
5, 6
1A, 1B
2A, 2B
Phase 1 of the Stepping Motor is connected between Pin 3 and 4 of J1.
Phase 2 of the Stepping Motor is connected between Pin 5 and 6 of J1.
Typical 4, 6 and 8 lead motor configurations
1B
1B
1
1
5
5
2
2
1A
1A
6
6
4
8
3
7
4
8
2B
2A
2B
7
2A
3
4 Wire Parallel
6 Wire Motor
A Basic 8 Wire Motor
“Do’s, Don’ts and Important Notes”
Do not connect or disconnect motor wires while power is supplied
When using a 6 lead motor be sure to insulate/isolate unused wires.
The physical direction of the motor with respect to the direction input will depend on the connection
of the motor windings. To reverse the direction of the motor with respect to the direction input,
switch the wires on phase 1 or phase 2 of the outputs.
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OMD23-2 USERS MANUAL
DIP Switch (JP1) Location
The following picture shows the DIP Switch (JP1) location on the OMD23-2 board:
Setting the Output Current (JP1)
The phase current is set using DIP switches SW1 - SW6. Switches SW1 - SW3 set the Hold Current,
and switches SW4 - SW6 set the Run Current. See below for the settings as well as the values:
SW1
OFF
ON
OFF
ON
OFF
ON
OFF
ON
SW2
SW3
Hold Current
OFF
OFF
OFF
OFF
ON
OFF
ON
OFF
OFF
ON
OFF
ON
ON
ON
ON
ON
SW4
OFF
ON
OFF
ON
OFF
ON
OFF
ON
SW5
SW6
Run Current
OFF
OFF
OFF
OFF
ON
OFF
ON
OFF
OFF
ON
OFF
ON
ON
ON
ON
ON
Value
0A
0.3A
0.7A
1.0A
1.3A
1.7A
2.0A
2.0A
The actual motor current will vary based on a number of factors including motor characteristics, cable
length and shielding. The Rule of Thumb is to set the output current where reliable motion is achieved
without excessive motor heating.
“Do’s, Don’ts and Important Notes”
Apply minimal force when adjusting the switches or you risk damaging them.
Using low power values may cause a slight change in the motor resting position.
If a different Current setting is desired, please contact the factory prior to ordering. It can be preset
to your specifications.
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OMD23-2 USERS GUIDE
Microstep Resolution (JP1)
The number of microsteps per full step is selected by the 3 DIP switches according to the below table.
Note that the ‘ON’ position is labeled on the DIP switch unit.
Switch 7
Switch 8
Switch 9
Off
On
Off
On
On
Off
Off
On
On
On
Off
Off
Off
Off
On
Resolution
Full
1/2
1/4
1/8
1/16
Steps/Revolution
(1.8˚ motor)
200
400
800
1,600
3,200
Control Input
The control inputs are wired to J1. To create motor motion at least the STEP and VIN+ inputs need to
be wired. Note that since the inputs are electrically isolated from the internal circuitry of the OMD232, the high level voltage of the input signals needs to be provided as reference for the optocoupler
circuitry. The low level does not need to be provided in addition.
Pin #
7
Name
STEP
8
9
DIR
ENABLE
10
VIN+
Description
Stepping is triggered on every rising transition of the STEP
input. Minimum duration of the high and low level is 1µs.
Direction signal. If unconnected a high level is assumed.
If left unconnected or supplied with a high level, the drive is
enabled. A low level on this input will disable the drive.
High level of input signals STEP / DIR / ENABLE. This is
required as reference for the optocoupler circuitry.
For the allowable voltage range on the control inputs please see the section Electrical Specifications.
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OMD23-2 USERS MANUAL
Electrical Specifications
Symbol
VSUPPLY
Irun
Parameter
Supply voltage
Motor run
current
Ihold
Min.
12
Max.
40
1.6
Unit
V
A
Notes
Motor hold
current
0
A
VOPTO+
High level
voltage of
STEP/DIR/ENA
BLE inputs
5
V
Design target is 3.3V to 20V. Other
voltage levels to be tested.
RES
Stepping
resolution
128
128
Steps
per full
step
Set by firmware. Parent product
features 3 DIP switches allowing
settings between 2 and 256 steps per
full step.
fstep
Stepping
frequency
0
500000
Steps
per
second
The maximum stepping frequency is
gated by the optocoupler circuitry.
tlow/thigh
Minimum low /
high time for
STEP signal
2
Set by firmware. Parent product
features 3 DIP switches allowing
settings between 0 and 4A
Set by firmware. If there is no step
input for 2 seconds, the drive will
switch from Irun to Ihold. Parent product
features 3 DIP switches allowing
settings between 0 and 4A
us
Minimum Signal Timing
A step sequence is triggered with the rising edge of the Step Input.
Thermal Specifications
Operating Temperature…………………0 to +50° C
Storage Temperature…………………. -40 to +125° C
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OMD23-2 USERS GUIDE
Dimensions & Mounting
**MMD23-2 is a bare PCB Board that is intended to be mounted to a surface that has good heat
syncing properties. Call for further details
Design Tips
EMI (electromagnetic interference or electrical noise) can be a major source of problems when
integrating power drivers with microprocessor based devices. EMI is typically generated through
ground loops and AC power line disturbances. External devices such as, relays, coils, solenoids, arc
welders, motors, drivers, and other computer-based equipment are also sources of EMI.
The following design tips will help to prevent EMI from interfering with the system operation:
• Shield the driver and wiring by mounting it in its own metal enclosure as far away from noise
sources as possible.
• Ground motor shields only at the driver end.
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OMD23-2 USERS MANUAL
• Make sure that all power wiring (motor, AC, etc.) is away from the signal wiring (I/O,
communications lines, etc.).
• Mechanical grounds should all be tied to Earth at a single point. Chassis and motor grounds should
be tied to the frame and the frame to Earth.
• Ground all signal wiring to one point.
• Use solid-state relays or opto isolators whenever possible to isolate remote signals. Suppress all
mechanical relays with capacitors or MOV’s.
• Use shielded, twisted pair cables for the motor, I/O and communications wiring.
**************** WARNING ********************
LIVE CONNECTING/DISCONNECTING MOTORS WILL CAUSE DAMAGE THAT IS NOT
COVERED BY WARRANTY.
Optional Heat Sync Mount
The following picture shows the optional heat sync mounting for the OMD23-2. It is recommended
for when you are mounting this drive in an area that does not have heat syncing.
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OMD23-2 USERS GUIDE
APPENDIX
COPYRIGHT NOTICE
© 2011 Pro-Dex, Inc.
ALL RIGHTS RESERVED
This document is copyrighted by Pro-Dex, Inc. You may not reproduce, transmit, transcribe, store
in a retrieval system, or translate into any language in any form or by any means, electronic,
mechanical, magnetic, optical, chemical, manual, or otherwise, any part of this publication without
the express written permission of Pro-Dex, Inc.
DISCLAIMER
Pro-Dex, Inc., Oregon Micro Systems makes no representations or warranties regarding the
contents of this document. We reserve the right to revise this document, or make changes to the
specifications of the product described within it at any time without notice and without obligation to
notify any person of such revision or change.
LIMITED WARRANTY
Pro-Dex, Inc. warrants that the articles furnished are free from defect in material and workmanship
and perform to applicable, published Pro-Dex, Inc specifications for one year from date of
shipment. This warranty is in lieu of any other warranty express or implied. In no event will Pro-Dex,
Inc be liable for incidental or consequential damages as a result of an alleged breach of the
warranty. The liability of Pro-Dex, Inc. hereunder shall be limited to replacing or repairing, at its
option, any defective units which are returned f.o.b. Pro-Dex, Inc. Beaverton, Oregon address.
Equipment or parts which have been subject to abuse, misuse, accident, alteration, neglect or
unauthorized repair are not covered by warranty. Pro-Dex, Inc. shall have the right of final
determination as to the existence and cause of defect. As to items repaired or replaced, the
warranty shall continue in effect for the remainder of the warranty period, or for 90 days following
date of shipment by Pro-Dex, Inc. of the repaired or replaced part whichever period is longer. No
liability is assumed for expendable items such as lamps and fuses. No warranty is made with
respect to custom equipment or products produced to Buyer’s specifications except as specifically
stated in writing by Pro-Dex, Inc. and contained in the contract.
TECHNICAL SUPPORT
Pro-Dex, Inc., Oregon Micro Systems can be reached for technical support by any of the following methods:
1. Email:
[email protected]
2. Internet:
http://www.Pro-DexOMS.com
3. Telephone:
8:00 a.m. - 5:00 p.m. Pacific Standard Time
(503) 629-8081 or (800) 707-8111
4. Facsimile:
24 Hours
(503) 629-0688
5. USPS:
Pro-Dex, Inc., Oregon Micro Systems Inc
15201 NW Greenbrier Pkwy, B-1
Beaverton OR 97006
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OMD23-2 USERS MANUAL
RETURN FOR REPAIRS
Call Pro-Dex, Inc. – OMSs’ Customer Service at 503-629-8081 or (800) 707-8111 or email to: [email protected].
Explain the problem and we may be able to solve it on the phone. If not, we will give you a Return Materials
Authorization (RMA) number.
Mark the RMA number on the shipping label, packing slip and other paper work accompanying the return. We
cannot accept returns without an RMA number.
Please be sure to enclose a packing slip with the RMA number, serial number of the equipment, reason for
return, and the name and telephone number of the person we should contact if we have further questions.
Pack the equipment in a solid cardboard box secured with packing material.
Ship prepaid and insured to:
PRO-DEX, INC. - OMS
15201 NW Greenbrier Pkwy, B1
Beaverton, OR 97006
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