Designing a NextMove PCI Breakout Unit

Transcription

1 Designing a NextMove PCI Breakout Unit MN1277BU Issue 1.0 MN1277BU 05/2000

2 .

3 Copyright and Safety Information Copyright Baldor Optimised Control Ltd All rights reserved. This manual is copyrighted and all rights are reserved. This document or attached software may not, in whole or in part, be copied or reproduced in any form without the prior written consent of Baldor Optimised Control. Baldor Optimised Control makes no representations or warranties with respect to the contents hereof and specifically disclaims any implied warranties of fitness for any particular purpose. The information in this document is subject to change without notice. Baldor Optimised Control assumes no responsibility for any errors that may appear in this document. MINT is a registered trademark of Baldor Optimised Control Ltd. Windows 95, Windows 98 and Windows NT are registered trademarks of the Microsoft Corporation. Limited Warranty For a period of one (1) year from the date of original purchase, BALDOR will repair or replace without charge controls which our examination proves to be defective in material or workmanship. This warranty is valid if the unit has not been tampered with by unauthorized persons, misused, abused, or improperly installed and has been used in accordance with the instructions and/or ratings supplied. This warranty is in lieu of any other warranty or guarantee expressed or implied. BALDOR shall not be held responsible for any expense (including installation and removal), inconvenience, or consequential damage, including injury to any person or property caused by items of our manufacture or sale. (Some states do not allow exclusion or limitation of incidental or consequential damages, so the above exclusion may not apply.) In any event, BALDOR s total liability, under all circumstances, shall not exceed the full purchase price of the control. Claims for purchase price refunds, repairs, or replacements must be referred to BALDOR with all pertinent data as to the defect, the date purchased, the task performed by the control, and the problem encountered. No liability is assumed for expendable items such as fuses. Goods may be returned only with written notification including a BALDOR Return Authorization Number and any return shipments must be prepaid. Baldor Optimised Control Ltd Hotwell Road Bristol BS8 4RP U.K. Telephone: +44 (0) Fax: +44 (0) sales@baldor.co.uk Web site: Baldor Electric Company Telephone: Fax: sales@baldor.com web site: Baldor ASR GmbH Telephone: +49 (0) Fax: +49 (0) Baldor ASR AG Telephone: +41 (0) Fax: +41 (0) Australian Baldor Pty Ltd Telephone: Fax: Baldor Electric (F.E.) Pte Ltd Telephone: Fax: MN1277BU 05/2000 i

4 Designing a NextMove PCI Breakout Unit ii MN1277BU 05/2000

5 Copyright and Safety Information Safety Notice: Only qualified personnel should attempt the start-up procedure or troubleshoot this equipment. This equipment may be connected to other machines that have rotating parts or parts that are controlled by this equipment. Improper use can cause serious or fatal injury. Only qualified personnel should attempt to start-up, program or troubleshoot this equipment. Precautions: WARNING: Do not touch any circuit board, power device or electrical connection before you first ensure that no high voltage present at this equipment or other equipment to which it is connected. Electrical shock can cause serious or fatal injury. Only qualified personnel should attempt to start-up, program or troubleshoot this equipment. WARNING: Be sure that you are completely familiar with the safe operation of this equipment. This equipment may be connected to other machines that have rotating parts or parts that are controlled by this equipment. Improper use can cause serious or fatal injury. Only qualified personnel should attempt to program, start-up or troubleshoot this equipment. WARNING: Be sure that you are completely familiar with the safe programming of this equipment. This equipment may be connected to other machines that have rotating parts or parts that are controlled by this equipment. Improper programming of this equipment can cause serious or fatal injury. Only qualified personnel should attempt to program, start-up or troubleshoot this equipment. MN1277BU 05/2000 iii

6 Designing a NextMove PCI Breakout Unit WARNING: Be sure all wiring complies with the National Electrical Code and all regional and local codes. Improper wiring may result in unsafe conditions. WARNING: The stop input to this equipment should not be used as the single means of achieving a safety critical stop. Drive disable, motor disconnect, motor brake and other means should be used as appropriate. Only qualified personnel should attempt to program, start-up or troubleshoot this equipment. WARNING: Improper operation or programming of the control may cause violent motion of the motor shaft and driven equipment. Be certain that unexpected motor shaft movement will not cause injury to personnel or damage to equipment. Peak torque of several times the rated motor torque can occur during control failure. WARNING: The motor shaft will rotate during the homing procedure. Be certain that unexpected motor shaft movement will not cause injury to personnel or damage to equipment. CAUTION: To prevent equipment damage, be certain that the input power has correctly sized protective devices installed. CAUTION: To prevent equipment damage, be certain that input and output signals are powered and referenced correctly. iv MN1277BU 05/2000

7 Copyright and Safety Information CAUTION: To ensure reliable performance of this equipment be certain that all signals to/from the controller are shielded correctly. MN1277BU 05/2000 v

8 Designing a NextMove PCI Breakout Unit vi MN1277BU 05/2000

9 Manual Revision History Manual Revision History Issue Date BOCL Reference Comments /4/00 UM First issue. MN1277BU 05/2000 vii

10 Designing a NextMove PCI Breakout Unit viii MN1277BU 05/2000

11 Contents Introduction Design Information Connector Details and Signal Routing Power Supplies Interface Protection Digital I/O Stepper Drivers CAN Drivers PCB Layout Guidelines Signal Tracking Ground / Power Planes Connector Availability Appendix Appendix Appendix MN1277BU 05/2000 ix

12 Designing a NextMove PCI Breakout Unit x MN1277BU 05/2000

13 Introduction 1. Introduction 1 Chapter 1 gives an introduction to NextMove PCI breakout design. Baldor supply a Breakout Unit (part number PCI , PCI ) for the NextMove PCI motion controller to provide easy access to the controller interface signals. This document gives guidelines for the design of a custom breakout unit. Figure 1-1: Baldor NextMove PCI Breakout Board The circuit diagram for the Baldor NextMove PCI Breakout Unit is provided in Appendix 1. The circuit diagram is supplied for reference only and is not guaranteed to reflect the current design of the Breakout Unit. In this document the term ground refers to a common reference voltage to which signals are returned. The term earth refers to a safety earth. A machine ground is normally connected to the safety earth at some point. MN1277BU 05/

14 Designing a NextMove PCI Breakout Unit 12 MN1277BU 05/2000

15 Design Information 2. Design Information 2 Chapter 2 provides important information for the design of a custom breakout unit. 2.1 Connector Details and Signal Routing Figure 2-1 shows the 100-pin connector pin arrangement on the Baldor NextMove PCI Breakout Unit. The connector is available as a PADS or OrCAD schematic item and a PADS PCB library item: for OrCAD use the standard PCB footprints DCON.050/RS_ALT/TM/100 for the right-angle version and DCON.050/VS_ALT/TM/100 for the straight. Contact your Baldor distributor for the PADS library items. This pin numbering is as defined by AMP. Note: pin 2 is marked by a square pad on Baldor products Figure 2-1: 100-pin connector numbering (top view) MN1277BU 05/

16 Designing a NextMove PCI Breakout Unit Table 2-1: 100-pin connector signals Pin No. Signal Pin No. Signal 1 Analogue input Analogue input 1+ 2 Analogue input 0-52 Analogue input 1-3 Analogue input Analogue input 3+ 4 Analogue input 2-54 Analogue input 3-5 Demand 0 55 Demand 1 6 Demand 2 56 Demand 3 7 Analog GND 57 GND 8 GND 58 +5V 9 CAN 1 transmit 59 CAN 2 transmit 10 CAN 1 receive 60 CAN 2 receive 11 Encoder 2 \CHA 61 Encoder 0 \CHA 12 Encoder 2 CHA 62 Encoder 0 CHA 13 Encoder 2 \CHB 63 Encoder 0 \CHB 14 Encoder 2 CHB 64 Encoder 0 CHB 15 Encoder 2 \CHZ 65 Encoder 0 \CHZ 16 Encoder 2 CHZ 66 Encoder 0 CHZ 17 Encoder 3 \CHA 67 Encoder 1 \CHA 18 Encoder 3 CHA 68 Encoder 1 CHA 19 Encoder 3 \CHB 69 Encoder 1 \CHB 20 Encoder 3 CHB 70 Encoder 1 CHB 21 Encoder 3 \CHZ 71 Encoder 1 \CHZ 22 Encoder 3 CHZ 72 Encoder 1 CHZ 23 Master encoder \CHA 73 Master encoder \CHB 24 Master encoder CHA 74 Master encoder CHB 25 Master encoder \CHZ 75 Master encoder CHZ 26 Step Output V 27 Step Output 2 77 Direction Output 0 28 Step Output 1 78 Direction Output 2 29 Direction Output 1 79 Direction Output 3 30 Step Output 3 80 Digital Output Digital Output USR-V+ 32 Digital Output 9 82 Digital Output 8 33 Digital Output 7 83 USR-V+ 34 Digital Output 6 84 Digital Output 5 35 Digital Output 4 85 User GND 36 Digital Output 3 86 Digital Output 2 37 Digital Output 1 87 User GND 38 Digital Output 0 88 Common Digital Input Digital Input Digital Input Digital Input MN1277BU 05/2000

17 Design Information 41 Digital Input Digital Input Digital Input Digital Input Digital Input Digital Input 9 44 Digital Input Digital Input 8 45 Digital Input 7 95 Digital Input 5 46 Digital Input 6 96 Digital Input 4 47 Digital Input 3 97 Digital Input 1 48 Digital Input 2 98 Digital Input 0 49 Common Relay normally closed 50 Relay common 100 Relay normally open High-speed signals between the NextMove PCI and the breakout must be twisted with their returns. Table 2-2 shows the pairs that must be twisted. Power lines must also be twisted with their returns, and ideally step outputs 0, 1, 2 and 3 should be twisted with GND. Table 2-2: Twisted pairs Signal Return Analogue input 0+ Analogue input 0- Analogue input 1+ Analogue input 1- Analogue input 2+ Analogue input 2- Analogue input 3+ Analogue input 3- Encoder 0 CHA Encoder 0 /CHA Encoder 0 CHB Encoder 0 /CHB Encoder 0 CHZ Encoder 0 /CHZ Encoder 1 CHA Encoder 1 /CHA Encoder 1 CHB Encoder 1 /CHB Encoder 1 CHZ Encoder 1 /CHZ Encoder 2 CHA Encoder 2 /CHA Encoder 2 CHB Encoder 2 /CHB Encoder 2 CHZ Encoder 2 /CHZ Encoder 3 CHA Encoder 3 /CHA Encoder 3 CHB Encoder 3 /CHB Encoder 3 CHZ Encoder 3 /CHZ Master encoder CHA Master encoder /CHA Master encoder CHB Master encoder /CHB Master encoder CHZ Master encoder /CHZ MN1277BU 05/

18 Designing a NextMove PCI Breakout Unit 2.2 Power Supplies The NextMove PCI +5V rail is supplied by the PC. The maximum total current drain on the +5V rail from the breakout and any devices connected to the breakout must not exceed 500mA. The USR-V+ rail is used to supply the digital output drivers when a PNP output module is fitted to the NextMove PCI card. USR-V+ must be in the range 12 to 24V ±20% with respect to USR-GND. Current consumption depends on the digital output load. USR-GND should be connected to the machine ground to prevent high common-mode voltages in the output driver circuits. 2.3 Interface Protection It is recommended that all NextMove PCI inputs and outputs be filtered on the breakout board. The simplest filter is implemented with a capacitor from the signal to ground. The capacitor should be placed close to the signal connector, and ideally the ground will be a separate clean interface ground, to which all I/O will be decoupled see Figure 2-2. The value of the filter capacitor will depend on the signal; in general the capacitor should be of the largest value that will not degrade the signal. Practical values are 100pF on high-speed signals (encoder inputs, stepper outputs and digital inputs 0-3), 100pF on analog inputs and 10nF on other signals. breakout circuit ground clean interface ground I/O Figure 2-2: Decoupling interface signals to a clean ground The noise-immunity of the interface may be improved by including a resistor in the signal line before (i.e. on the source side of) the capacitor to form an RC filter. Table 2-3 gives the signal resistances on the NextMove PCI card, useful when selecting filter component values. 16 MN1277BU 05/2000

19 Design Information A typical filter resistor value is 100. In cases where the extra resistance is undesirable, the resistor may be replaced with an inductor. For example, to provide an impedance of 600 at 100 MHz an inductance of approximately 1 H is required the inductive impedance at, say, 10kHz is then Z L = 2πfL = 0.06Ω. The inductor must be rated to withstand the interface current. If there is a risk of high transient voltages on the signal lines, inputs should be protected with voltage-dependent resistors or Zener diode clamps. Table 2-3: NextMove PCI input / output resistances Signal Digital inputs 0 3 Digital inputs 4 19 Analog inputs Encoder inputs Analog outputs PNP digital outputs NPN digital outputs resistance 4.7k 4.7k 20k Digital I/O The digital output circuit on the NextMove PCI card is connected as shown in Figure 2-3 (note: this is a functional diagram, representing one digital output with the dotted sections indicating the NPN and PNP output module options). USR-V+ is clamped to +30V. If USR-V+ exceeds +30V the clamp diode will fail short-circuit, causing the 1A USR-V+ fuse to blow to prevent damage to the output drivers. MN1277BU 05/

20 Designing a NextMove PCI Breakout Unit Figure 2-3: Functional diagram of a NextMove PCI digital output Figure 2-4 shows the digital inputs. The fast inputs 0 to 3 are connected to high-speed TLP-115A isolators; the standard inputs 4 to 19 are connected to TLP280 isolators. There are two input common rails: COMMON1 for inputs 0 to 7, and COMMON2 for inputs 8 to 19. The input voltage is applied between the input and its associated common rail. The input voltage must be in the range 12V to 24V (±20%) to switch the input on (either polarity). 18 MN1277BU 05/2000

21 Design Information Figure 2-4: One high-speed and four standard NextMove PCI digital inputs MN1277BU 05/

22 Designing a NextMove PCI Breakout Unit 2.5 Stepper Drivers The NextMove PCI card generates TTL step and direction signals for stepper motors. The Baldor Breakout Unit uses the Baldor Stepper Output Driver (OPTO25-501) to convert the TTL levels to balanced line driver signals. The driver circuit is provided in Appendix 2; mechanical details are provided in Appendix CAN Drivers The NextMove PCI card generates complementary TTL CAN signals. The Baldor Breakout Unit uses the Baldor Isolated CAN Driver (OPTO25-502) and the Baldor Non-Isolated CAN Driver (OPTO25-503) on the CANopen and Baldor CAN channels respectively. The CAN driver circuits are provided in Appendix 2; mechanical details are provided in Appendix MN1277BU 05/2000

23 PCB Layout Guidelines 3. PCB Layout Guidelines 3 Chapter 3 gives advice on PCB layout for custom breakout designs. PCB layout is one of the most important factors influencing noise-immunity and emissions in a design. It is recommended that the guidelines given below be followed when designing breakout units. However, there may be overriding engineering constraints which conflict with some of the layout rules. In these circumstances the acceptability of a compromise between the conflicting constraints must be considered; it may be found that a design which has a PCB layout in some areas counter to one or several of the recommendations given below, while not performing ideally will nevertheless be acceptable. 3.1 Signal Tracking The differential analog and encoder input signals should be routed as pairs, with the signal as close to the return as possible see Figure 3-1 for examples of good and bad differential routing. The demand outputs should be routed as pairs with analog ground. Critical tracks are those carrying high-speed signals (signals with a high di/dt e.g. encoder inputs) and noise-sensitive signals (e.g. analog inputs and outputs, fast digital inputs). Critical tracks should be routed on layers either side of a ground plane or ground / power plane pair, and should be kept as far from the edges of the board as possible. The use of a guard ring around critical track sections is recommended to provide a low impedance ground for incoming and outgoing radiated noise. A guard ring takes the form of an open-ended loop of track that surrounds the critical section and is connected to ground at one end only. The guard ring must not carry any current, other that than radiated noise currents i.e. make no connections to the guard ring. MN1277BU 05/

24 Designing a NextMove PCI Breakout Unit Return GOOD BAD Figure 3-1: Routing differential signals 3.2 Ground / Power Planes Power and ground planes should be next to each other in the PCB layer stack. A bypass capacitor of 10 to 470 F should be connected between the power plane and its ground in each circuit section. The value of the bypass capacitor depends on the circuit function: its purpose is to act as a supply voltage reservoir and ripple filter for the section of circuit to which it is fitted. If a transient current demand from a circuit can be supplied by a local reservoir capacitor the transient currents routed around other sections of the PCB power lines are reduced. In general, the larger the PCB and the greater the distance from the circuit section to the supply the higher the value of bypass capacitor required. Power planes should also be well decoupled (the bypass capacitor is not effective as a highfrequency decoupler). Decoupling capacitor values depend on signal frequencies and, particularly, rise times: values of 10 to 100nF are recommended for breakout designs. Decoupling capacitors should be included close to every IC on the breakout board, and close to every section of high-speed circuitry. The ground plane should overlap the power plane at the edges of the board by a distance of approximately 10 times the separation of the planes, in order to soften the edge discontinuity and reduce emissions. Analog and digital sections of the board should be kept separate, and should use separate ground planes. If the analog and digital circuits must share a ground, the ground plane should be segmented with an unmetallised moat see Figure 3-2. Digital tracks should not cross the analog ground plane, and vice-versa. 22 MN1277BU 05/2000

25 PCB Layout Guidelines If two ground planes are used, for example a signal ground and a chassis ground, the risk of RF resonance is reduced by stitching the ground planes together with frequent closely-spaced vias. See Figure 3-3. DIGITAL CIRCUITS GROUND UNMETALLISED MOAT Figure 3-2: Segmented ground plane Via MINIMISE GROUND LOOP AREAS Figure 3-3: Stitching ground planes to reduce RF resonance MN1277BU 05/

26 Designing a NextMove PCI Breakout Unit 24 MN1277BU 05/2000

27 Connector Availability 4. Connector Availability 4 Chapter 4 suggests sources for the 100-pin connector. The 100 way connectors used for the Baldor NextMove PCI Cable (CBL021-50X) are available from a number of manufacturers. Table 4-1 gives some alternatives. Manufacturer Table 4-1: 100-pin connector alternatives Manufacturer s part number Straight Right-angle Baldor (AMP) ( CO0005A17 CO0005A16 AMP (www. connect.amp.com) M ( N102XX-62X2VC N102XX-52X2VC Honda Connectors (screw-lock version only) ( PCS PCS MN1277BU 05/

28 Designing a NextMove PCI Breakout Unit 26 MN1277BU 05/2000

29 Appendix 1 5. Appendix 1 Appendix 1 provides the circuit diagram for the Baldor NextMove PCI Breakout Unit. MN1277BU 05/

30 Designing a NextMove PCI Breakout Unit 28 MN1277BU 05/2000

31 Appendix 1 MN1277BU 05/

32 Designing a NextMove PCI Breakout Unit 30 MN1277BU 05/2000

33 Appendix 2 6. Appendix 2 Appendix 2 provides circuit diagrams for the Baldor Stepper and CAN Driver modules. Figure A2-1: Stepper Driver (OPTO25-5-1) circuit diagram MN1277BU 05/

34 Designing a NextMove PCI Breakout Unit Figure A2-2: Isolated CAN Driver (OPTO25-502) circuit diagram Figure A2-3: Non-Isolated CAN Driver (OPTO25-503) circuit diagram 32 MN1277BU 05/2000

35 Appendix 3 7. Appendix 3 Appendix 3 provides mechanical details for the Baldor Stepper and CAN Driver modules. Dimensions in mm, 0 1mm, mm, mm. Figure A3-1: Stepper Module (OPTO25-501) mechanical details (connectors are Samtec 2mm SMM series sockets) MN1277BU 05/

36 Designing a NextMove PCI Breakout Unit Figure A3-2: Isolated CAN Module (OPTO25-502) mechanical details Figure A3-3: Non-Isolated CAN Module (OPTO25-503) mechanical details 34 MN1277BU 05/2000