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Performance Motion Devices Juno MC71112, User Manual

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Performance Motion Devices Juno MC71112 User Manual Download Page 79

Juno Step Motor Control IC User Guide 

79

13

13.Drive & DC Bus Safety 

In This Chapter



Drive & DC Bus Safety



Current Foldback



Settable Parameters



Signal Processing

13.1 Drive & DC Bus Safety

The Juno step motor ICs provide sophisticated drive and DC Bus safety features. These features include 
overtemperature monitoring, over and under voltage monitoring, overcurrent monitoring, and current foldback.

The following sections provide detailed information for these drive and DC Bus safety related features.

13.1.1 Overtemperature Protection

Juno supports a 

Temperature

 sensor input to continuously monitor the temperature of the power electronics or another 

part of the motion system. Although various temperature sensors may be used, the most common type of sensor is a 
thermistor.

The value of the temperature sensor and downstream analog conditioning circuitry determine the overall temperature 
range that can be measured. The overall temperature sense range should be 15% to 25% above the highest expected 
temperature.

The 

Temperature

 signal input expects a voltage in the range of 0V to 3.3V representing the sensed temperature. Both 

temperature-voltage-increasing (voltage increases with increasing temperature) and temperature-voltage-decreasing 
(voltage decreases with increasing temperature) thermistors are supported. For voltage increasing thermistors 0.0V 
represents the lowest possible temperature, and for voltage decreasing thermistors 3.3V represents the lowest possible 
temperature.  

The overtemperature threshold is user programmable. The sign of the overtemperature threshold selects whether the 

Temperature

 input increases or decreases with rising temperature; positive thresholds indicate voltage increase while 

negative thresholds indicate voltage decrease. The actual limit threshold utilized by Juno for the comparison is the 
absolute value of the specified limit value. The magnitude of the numerical threshold value has a range of 0 to 32,767 
with 0 being the lowest readable temperature and 32,767 the highest. 

In addition to the settable overtemperature threshold Juno supports a settable temperature hysteresis. This function is 
used to avoid spurious re-triggering of an overtemperature event.

Example

A temperature-voltage-increasing thermistor and associated analog processing circuitry generate a voltage of 2.9V when 
the amplifier is at the hottest safely operable temperature. The overtemperature limit specified should thus be set to 
32,768 * 2.9V/3.3V = 28,796. Later the design is changed so that a voltage decreasing thermistor is used. With a voltage 
decreasing thermistor an overtemperature limit of -28,796 would be programmed.

Summary of Contents for Juno MC71112

Page 1: ...Performance Motion Devices Inc 1 Technology Park Drive Westford MA 01886 Juno Step Motor Control IC User Guide Revision 1 2 May 2019 ...

Page 2: ...n permission of Performance Motion Devices Inc The information contained in this document is subject to change without notice No part of this document may be reproduced or transmitted in any form by any means electronic or mechanical for any purpose without the express written permission of Performance Motion Devices Inc Copyright 1998 2019 by Performance Motion Devices Inc Juno Atlas Magellan ION...

Page 3: ...e support system an aircraft control system and a motor vehicle control system would all be considered Unauthorized Applications and use of a Performance Motion Devices Inc product in such a system would not be warranted or approved by Performance Motion Devices Inc By using any Performance Motion Devices Inc product in connection with an Unauthorized Application the customer agrees to defend inde...

Page 4: ...developer kit supports the two 56 pin VQFN Juno step motor control ICs MC74113N and MC75113N Juno Velocity Torque Control IC User Guide Complete description of all members of the Juno Velocity Torque Control IC family including the MC71112 MC71112N MC73112 MC73112N MC74113 MC74113N MC75113 MC75113N MC71113 MC73113 and MC78113 ICs Includes features and functions with detailed theory of operations J...

Page 5: ...et 25 4 5 Pulse Direction 25 5 Pinouts and Pin Descriptions 27 5 1 Pinouts for the MC74113 27 5 2 Pinouts for the MC74113N 28 5 3 Pinouts for the MC75113 29 5 4 Pinouts for the MC75113N 30 5 5 MC74113 MC74113N MC75113 MC75113N IC Pin Descriptions 31 6 Juno IC Configuration in the Production Application 35 6 1 Loading the NVRAM 35 6 2 Analog Signal Calibration in the Production Application 36 7 Ope...

Page 6: ...rrupts 76 12 5 Trace 76 12 6 Settable Parameters 77 13 Drive DC Bus Safety 79 13 1 Drive DC Bus Safety 79 13 2 Current Foldback 81 13 3 Settable Parameters 83 13 4 Signal Processing 83 14 Power up Configuration Storage NVRAM 87 14 1 Power up 87 14 2 NVRAM 87 14 3 Initialization Control 87 14 4 Settable Parameters 88 14 5 Signal Processing 88 15 Application Notes MC74113 MC75113 91 15 1 General Des...

Page 7: ...2 Pulse Direction Processing Circuitry 51 8 3 Direct Input SPI Format 52 8 4 Quadrature Encoder Processing Circuitry 53 9 1 Current Loop Control Flow Diagram 55 9 2 Typical Current Signal Processing Circuitry 57 10 1 PWM High Low Encoding 60 10 2 PWM High Low Signal Generation 60 10 3 Two phase Step Motor Bridge Configuration 61 10 4 Sign Magnitude PWM Encoding 63 10 5 Sign Magnitude PWM Step Moto...

Page 8: ...o Step Motor Control IC User Guide 15 7 Step Motor Drive with 10A Continuous Current Rating 109 15 8 Step Motor Control with Sign Magnitude Signal 111 15 9 Two Axis Step Motor Drive With Multi Axis Magellan 113 ...

Page 9: ... quadrature encoder index and Hall sensor signals It interfaces to external bridge type switching amplifiers utilizing PMD Corp s proprietary current and switch signal technology for ultra smooth ultra quiet motor operation Juno ICs can be pre configured via NVRAM for auto power up initialization and standalone operation with SPI Serial Peripheral Interface direct analog input or pulse direction c...

Page 10: ... MC78113 MC73112 MC73112N MC73113 MC78113 Motor Type Control Mode Motor Type Step motor DC Brush DC Brush Brushless DC Brushless DC Velocity Torque current Position outer loop Host Interface Serial point to point Serial multi drop SPI CANbus Command Input Analog velocity or torque SPI velocity or torque Pulse direction SPI position increment Motion I O Quadrature encoder input MC74113 MC74113N onl...

Page 11: ...d testing Pro Motion autotuning and axis wizard setup software Complete Juno manuals or PDFs Extensive application schematic examples Developer Kit P N Juno IC Installed Motor supported Comments DK71112 MC71112 DC Brush Torque control DK71113 MC71113 DC Brush Velocity torque control DK73112 MC73112 Brushless DC Torque control DK73113 MC73113 Brushless DC Velocity torque control DK74113 MC74113 Ste...

Page 12: ...The Juno IC Family 12 Juno Step Motor Control IC User Guide 1 This page intentionally left blank ...

Page 13: ...ps Motor output modes PWM High Low Individual high and low drive signals for each bridge switch Sign Magnitude PWM Separate sign and magnitude drive signal for each phase of switching bridge Current loop rate 19 53 kHz Current measurement resolution 12 bits PWM resolution rates 1 1 536 20 kHz 1 768 40 kHz 1 384 80 kHz 1 256 120 kHz DC Bus safety signals Brake BusVoltage BusCurrentSupply Temperatur...

Page 14: ...de 2 Output limiting I2 t current and voltage limit Microsteps per full step 1 to 256 Maximum encoder rate 40 Mcounts sec Position capture triggers Index signal Internal RAM 6 144 16 bit words Maximum number of simultaneous trace variables 4 NVRAM 1 024 16 bit words ...

Page 15: ...er Guide 15 2 2 2 Physical Dimensions 64 PIN TQFP Package All dimensions are in millimeters Figure 2 1 64 Pin TQFP Physical Dimensions Notes 1 Juno IC is RoHS compliant and free of Bromine and Antimony based flame retardants 2 Moisture sensitive level MSL 3 ...

Page 16: ...cal Dimensions Notes 1 Juno IC is RoHS compliant and free of Bromine and Antimony based flame retardants 2 Moisture sensitive level MSL 3 Thermal Pad 5 4 5 2 Pin 1 Indicator SQ 5 3 5 1 0 40 0 25 0 15 0 60 0 40 7 15 6 85 SQ Bottom View 1 0 0 8 0 20 Seating Plane 0 05 0 00 1 14 15 28 29 42 43 56 Front View 42 28 15 14 1 58 43 29 Pin 1 Indicator ...

Page 17: ...e 0 3V to 2 5V Analog voltage range with respect to AnalogGND AnalogVcc 0 3V to 4 6V Input voltage Vi 0 3V to 4 6V Output voltage Vo 0 3V to 4 6V Input clamp current Ii clamp peak 20 mA Input clamp current Ii clcontinuous 2 mA Output clamp current Io clamp 20 mA Package thermal impedance 64 pin TQFP package JA 56 5 C W Package thermal impedance 56 pin VQFN package JA 34 8 C W Junction temperature ...

Page 18: ...Functional Characteristics 18 Juno Step Motor Control IC User Guide 2 This page intentionally left blank ...

Page 19: ...erature 40 C 105 C Note 2 Tj Operating junction temperature 40 C 150 C Input Voltage Vih Logic 1 input voltage 2 0V Vcc 0 3V Vil Logic 0 input voltage 0 3V 0 8V Output Voltage Voh Logic 1 Output Voltage 2 4V Io 4 mA Vcc 0 2V Io 50 μA Vol Logic 0 Output Voltage 0 4V Io 4 mA Other Iout Tri state output leakage current 2 μA 2 μA Vo 0 or Vcc Iin Input current 2 μA 205 μA Vcc 3 3V with internal pullup ...

Page 20: ...configured to be active high Vanalog Analog input voltage range 0 3 3V With respect to AnalogGND Cai Analog input capacitance 5 pF typical Ednl Differential nonlinearity error Difference between the step width and the ideal value No missing codes 1 1 LSB Einl Integral nonlinearity error Maximum deviation from the best straight line through the ADC transfer characteristics excluding the quantizatio...

Page 21: ...k high to SPIXmt valid delay time T27 21 nSec SPIXmt data valid time after SPIClock low T28 T25 SPIRcv setup time before SPIClock high T29 25 nSec SPIRcv valid time after SPIClock low T30 25 nSec Last SPIClock low to SPIEnable high T31 25 Timing Interval No Min Max Power on pulse duration driven by device typical note 1 T32 600 μSec Device ready outputs initialized typical T33 2 mSec Timing Interv...

Page 22: ...Electrical Characteristics 22 Juno Step Motor Control IC User Guide 3 This page intentionally left blank ...

Page 23: ...r Quadrature Encoder Input SPI Timing Power On Timing Warm Reset Pulse Direction For the values of Tn please refer to the table in Section 3 2 AC Characteristics for more information 4 1 Quadrature Encoder Input Figure 4 1 Quad Encoder Timing T4 Quad A Quad B T5 Index T4 T5 T6 ...

Page 24: ...ser Guide 4 4 2 SPI Timing Figure 4 2 SPI Timing 4 3 Power On Timing Figure 4 3 Power On Timing SPIClock SPIEnable SPIXmt SPIRcv T23 T24 T25 T31 T28 T27 T29 T30 T26 data is valid data must be valid T32 Inputs note 2 T33 Reset Vcc AnalogVcc I O Pins ...

Page 25: ...e 25 4 4 4 Warm Reset Figure 4 4 Warm Reset Timing Please refer to Note 2 in Section 3 2 4 Warm Reset for more information 4 5 Pulse Direction Figure 4 5 Pulse Direction Timing T35 Inputs note Code Dependent Reset I O Pins Pulse Direction T38 T38 T39 T40 ...

Page 26: ...Timing Diagrams 26 Juno Step Motor Control IC User Guide 4 This page intentionally left blank ...

Page 27: ...ignA PWMHighB PWMLowB PWMHighC PWMMagC PWMLowC PWMSignC PWMHighD PWMLowD Reset AmplifierEnable Brake Enable QuadA QuadB Index AtRest FaultOut SrlXmt SrlRcv Pulse SPIClock SPIXmt Direction SPIRcv SPIEnable HostInterrupt CurrentA CurrentB CurrentC CurrentD BusVoltage BusCurrentSupply Temperature 15 16 AnalogVcc 29 57 Vcc GND 6 28 41 42 58 60 AnalogGND 17 18 24 FltCap 5 43 59 56 55 54 53 51 50 39 38 ...

Page 28: ... Reset AmplifierEnable Brake Enable QuadA QuadB Index AtRest FaultOut SrlXmt SrlRcv Pulse SPIClock SPIXmt Direction SPIRcv SPIEnable HostInterrupt CurrentA CurrentB CurrentC CurrentD BusVoltage BusCurrentSupply Temperature 13 14 AnalogVcc 26 50 Vcc GND 4 25 36 37 51 53 AnalogGND 15 21 FltCap 3 38 52 49 48 47 46 45 44 34 33 5 22 32 1 55 56 2 23 40 24 28 29 30 31 39 43 12 16 10 18 11 8 7 No Connect ...

Page 29: ...et AmplifierEnable Brake Enable AtRest FaultOut SrlXmt SrlRcv Pulse SPIClock SPIXmt Direction SPIRcv SPIEnable HostInterrupt CurrentA CurrentB CurrentC CurrentD BusVoltage BusCurrentSupply Temperature 15 16 AnalogVcc 29 57 Vcc GND 6 28 41 42 58 60 AnalogGND 17 18 24 FltCap 5 43 59 56 55 54 53 51 50 39 38 7 3 37 2 35 52 27 32 33 34 36 44 46 14 19 12 21 13 10 9 No Connect 1 4 8 11 20 22 23 25 26 30 ...

Page 30: ...D PWMLowD Reset AmplifierEnable Brake Enable AtRest FaultOut SrlXmt SrlRcv Pulse SPIClock SPIXmt Direction SPIRcv SPIEnable HostInterrupt CurrentA CurrentB CurrentC CurrentD BusVoltage BusCurrentSupply Temperature 13 14 AnalogVcc 26 50 Vcc GND 4 25 36 37 51 53 AnalogGND 15 21 FltCap 3 38 52 49 48 47 46 45 44 34 33 5 22 32 1 23 40 24 28 29 30 31 39 43 12 16 10 18 11 8 7 No Connect 2 6 9 17 19 20 27...

Page 31: ...sing the SetDrivePWM command PWMLowA B C D signals encode the low side drive for a switching bridge with separate high low controls The default encoding is active high however this can be changed using the SetDrivePWM command PWMMagA C signals encode the magnitude of a pulse width modulated output for use with switching bridges with sign magnitude controls The default encoding is active high howev...

Page 32: ...nused this pin may be left unconnected Pulse SPIClock 33 29 in Pulse provides a pulse step signal for the pulse direction command input function A step occurs when this signal transitions from a high state to a low state however the interpretation of this signal can be programmed SPIClock inputs the clock signal used with synchronous serial transfer on the host communication SPI bus If unused this...

Page 33: ...o to 3 3V If unused this signal should be connected to AnalogGND Temperature 9 7 in This pin inputs an analog voltage representing the temperature of the amplifier or other monitored circuitry The allowed signal input range is zero to 3 3V If unused this signal should be connected to AnalogGND AnalogVcc 16 15 13 14 N A These pins are connected to the analog input supply voltage which must be in th...

Page 34: ...1 20 22 23 30 40 47 48 6 9 17 19 20 27 35 42 N A These pins must be left unconnected Thermal pad N A T Pad N A Thermal pad on bottom of 56 pin VQFN IC package must be connected to GND For 64 pin TQFP package there is no thermal pad Name 64 Pin TQFP Pin 56 Pin VQFN Pin Direction Description ...

Page 35: ...s that load the control registers via an on board microprocessor use specially formatted host commands sent over the serial port For more information refer to the Juno Velocity Torque Control IC User Guide 6 1 Loading the NVRAM 6 1 1 NVRAM Programming via Juno DK IC Socket The 64 pin TQFP package Juno DK includes an IC socket that can be used to program the NVRAM on 64 pin Juno ICs prior to solder...

Page 36: ... desired calibration of the analog inputs is recommended The signals that can be calibrated for the Juno step motor ICs are CurrentA CurrentD For more information refer to Section 9 2 3 Current Signal Calibration When a microprocessor is on the user PCB generally this microprocessor is used to send the serial host commands needed to calibrate the analog inputs as part of the power up sequence Anot...

Page 37: ...ower cycle is to execute the calibration on the assembled PCB using a 3 pin UART programming cable The derived calibration offsets are stored into NVRAM and recalled automatically thereafter by Juno at each power up PMD Corp provides easy to use standalone Windows compatible executables for this function For more information see Section 6 1 2 NVRAM Programming Via 3 pin UART Cable ...

Page 38: ...Juno IC Configuration in the Production Application 38 Juno Step Motor Control IC User Guide 6 This page intentionally left blank ...

Page 39: ...lues are used and information is sent by serial from a host device such as a microprocessor or cable connected PC to configure the Juno IC for a specific application Depending on how Juno has been configured an external pulse and direction or SPI Serial Peripheral Interface data stream may be used for the incremental position command value Alternatively an internal profile generator commanded via ...

Page 40: ...nchronization and control is optimal over the entire operating range of the driven step motor A number of safety features are incorporated into the Juno ICs including I2 t current limiting brake signal input DC bus overvoltage and undervoltage detect overcurrent detect and overtemperature detect In addition the MC74113 and MC74113N devices accept a quadrature encoder input which can be used for au...

Page 41: ...position and uses pre programmed settings such as the desired current and the number of microsteps per full step to synthesis the two phase step motor waveform This module also provides stall detection via optional quadrature encoder feedback signals Current Loop This module inputs the commanded current for each step motor phase along with the measured current for each phase and uses a sophisticat...

Page 42: ...ion 7 4 2 SPI Control of Step Motors Figure 7 5 Step Motor SPI Control Diagram Applications General purpose step motor drive laboratory automation liquid handling scientific instruments printers XY stages In this configuration a microprocessor or other external profile generator commands the position via an SPI bus and optional at rest signal Encoder feedback signals which can be used with the MC7...

Page 43: ...d to a specific application Juno s serial port may be used to program these control parameters using what are known as host commands Host commands are data packets that follow a particular format and protocol Alternatively the NVRAM may be used to auto load the control parameters upon power up In this case the format of the stored NVRAM data closely resembles the serial host command packets Most h...

Page 44: ...rom the apostrophe to the end of the line are a comment Pro Motion always inserts as the first entry ScriptVersion indicating the script file version format that the file was stored in This entry is not stored into the Juno IC but allows past and future versions of Pro Motion to interpret the script file correctly Numbers default to decimal interpretation but can be forced for hexadecimal interpre...

Page 45: ...be user programmed This is shown in the table below Juno serial communications must follow a specific format For complete information on the SetSerialPortMode command as well as other commands in Juno s serial RS232 host command protocol refer to the Juno Velocity Torque Control IC Programming Reference Most users will not directly edit the script files and will instead rely on Pro Motion to creat...

Page 46: ...Operational Overview 46 Juno Step Motor Control IC User Guide 7 This page intentionally left blank ...

Page 47: ...s are processed by Juno and the resultant count is stored in a 32 bit position register Pulse direction input is a popular and easy to use method to continuously stream a commanded position to the Juno IC For more information on signal format and timing see Section 3 2 5 Pulse Direction Direct input SPI is an alternate available method of position command input When direct input SPI is selected th...

Page 48: ...n Note that this represents the theoretical positioning resolution but does not necessarily mean the motor will have this precision or even this number of actual resolved mechanical positions That depends on a number of application characteristics including system friction drive torque and motor linearity The minimum number of microsteps per full step is one phase counts setting of four The maximu...

Page 49: ...n capture register and the capture received indicator of the Event Status register is set The capture register can be read using serial host commands Reading the position capture register causes the trigger to be re armed allowing for more captures to occur 8 4 2 Stall Detection Juno step motor control ICs can actively monitor the encoder position and automatically detect when the step motor has s...

Page 50: ...ent Specified value has a range of 0 to 32 767 and determines the step motor s drive current command To convert to of maximum output multiply by 100 32 767 Holding current SetCurrent Specified value has a range of 0 to 32 767and determines the step motor s holding current command To convert to of maximum output multiply by 100 32 767 Encoder to microstep ratio SetEncoderStepRatio Two specified val...

Page 51: ...pported by the Juno step motor ICs is a write by the external circuitry of a 16 bit position command data word This 16 bit value represents the relative incremental distance that the position command has changed since the previous SPI relative position command write The write format is shown in Figure 8 3 The external circuitry serves as the SPI master generating the clock and the enable and trans...

Page 52: ...the watchdog countdown period a watchdog error occurs resulting in the drive exception flag of the Event Status register being set For more information see Section 12 1 1 Event Status Register Juno can be programmed to take various actions when a watchdog timeout occurs such as disabling the motor output The mechanism to program and process these functions is called event handling and described in...

Page 53: ...Index signal provides a capture trigger for the instantaneous up down quadrature position This input signal is most often tied to the encoder s index output but this is not required 8 6 3 1 Typical Quadrature Encoder Processing Circuitry Figure 8 4 Quadrature Encoder Processing Circuitry Figure 8 4 shows a typical circuit for processing differential quadrature and index signals The pull up and pul...

Page 54: ...Microstep Waveform Generation 54 Juno Step Motor Control IC User Guide 8 This page intentionally left blank ...

Page 55: ...e motor output module which generates the precise PWM pulse width modulation timing output signals to control external switching circuitry To control the current loop three parameters are specified for both a D loop and a Q loop by the user Kp Ki and Ilimit Two of these are gain factors for the PI proportional integral controller one is a limit for the integral contribution Determining correct Kp ...

Page 56: ...rolloff on the lower end of the frequency range Juno s operating with PWM frequencies of 40 kHz 80 kHz or 120 kHz operating in low or normal noise environments may consider a rolloff on the higher end of this range Parameter Host Command Mnemonic Range Description Set Operating Mode register SetOperatingMode Specified value is a bit oriented mask determining the state of the command source current...

Page 57: ...value of the user s external sense resistors and analog conditioning circuitry determine the overall controllable current range of the step motor amplifier The overall current sense range should be 25 to 50 above the largest expected peak current The user commandable current range is 80 of the current sense range Example A step motor application will require a peak current in each phase of 7 5 amp...

Page 58: ...o out external analog input offsets that may exist while the motor coils are not being driven by the amplifier and the motor is not moving This calibration sequence will automatically measure and set the offsets so that the leg current analog inputs are zeroed out Because a number of samples are taken and averaged 100 mSec should be allowed for this operation to complete Analog offsets unless expl...

Page 59: ...ted motor movement during startup by default the motor output module is disabled To enable motor output the user must enable the corresponding flag of the Operating Mode register 10 1 PWM High Low Motor Output Mode The Juno step motor control ICs can control high efficiency MOSFET or IGBT power stages with individual high low switch input control Step motors are driven in a two H Bridge configurat...

Page 60: ... requires a minimum amount of off time to allow the charge pump circuitry to refresh This parameter specifies this refresh time and has units of nSecs The related parameter of refresh time period which is the time interval between these off time refreshes has units of current loop cycles It is also possible to control the maximum allowed PWM duty cycle This may be useful to limit the effective vol...

Page 61: ...tional must be connected to the bridge to control when the bridge should be active For more information on the AmplifierEnable signal see Section 10 3 AmplifierEnable Since there is no separate high and low side signal to control the switches the bridge itself rather than the Juno IC must handle some details of switch timing generation such as shoot through protection Along those lines the dead ti...

Page 62: ...nge Description Set Operating Mode register SetOperatingMode Specified value is a bit oriented mask determining the state of the command source current loop and motor output enable disable flags PWM switching frequency SetDrivePWM Two parameter command the first must be 3 and the second is a fixed code value setting the PWM frequency to either 20 40 80 or 120 kHz PWM dead time SetDrivePWM Two para...

Page 63: ...de which ranges from 0 to 100 as shown in Figure 10 4 A high signal on this pin means the motor coil should be driven with voltage A second pin outputs the sign of the motor command by going high for positive sign and low for negative PWMLowC 50 44 Digital low side drive output for motor phase B positive coil terminal PWMHighD 39 34 Digital high side drive output for motor phase B negative coil te...

Page 64: ...ters For more information on Juno host commands refer to the Juno Velocity Torque Control IC Programming Reference Parameter Host Command Mnemonic Range Description Set Operating Mode register SetOperatingMode Specified value is a bit oriented mask determining the state of the command source current loop and motor output enable disable flags PWM switching frequency SetDrivePWM Two parameter comman...

Page 65: ... Section 12 3 Event Action Processing If either the motor output module is enabled or if the brake function is active than the AmplifierEnable signal is active If both the motor output module is disabled and the brake function is inactive than the AmplifierEnable signal is inactive 10 4 Brake The MC78113 Brake signal input provides a high speed PWM output disable that may be useful for safety prot...

Page 66: ...ent that caused the discontinuation of function must be reset For more information on Juno event processing see Section 12 3 Event Action Processing The braking function is only available with the PWM control mode set to PWM High Low When the output mode is Sign Magnitude PWM the Brake signal can only control a disable function ...

Page 67: ...e user specified target velocity is reached The sign of the velocity parameter determines the initial direction of motion Therefore the velocity value sent to Juno can have a positive value for positive direction motion or a negative value for negative direction motion The axis decelerates at the user specified target deceleration when a new velocity is specified with a smaller value in magnitude ...

Page 68: ...06 035 The acceleration command must achieve the desired velocity in 120 sec 9 765 cycles sec 1 172 cycles Therefore the acceleration is 13 825 microsteps cycle 1 172 cycle 01180 microsteps cycle2 To scale this command to the 8 24 format used for the Juno target acceleration we multiply by 224 giving a 32 bit acceleration command value to send of 01180 16 777 216 197 971 11 3 Profile Stop Events J...

Page 69: ...ion 11 2 Profile Parameter Scaling Parameter Host Command Mnemonic Range Description Velocity SetVelocity Specified value has a range of 2 147 483 648 to 2 147 483 647 and specified the profile target velocity Acceleration SetAcceleration Specified value has a range of 0 to 2 147 483 647 and specified the profile target acceleration Deceleration SetDeceleration Specified value has a range of 0 to ...

Page 70: ...Internal Profile Generation 70 Juno Step Motor Control IC User Guide 11 This page intentionally left blank ...

Page 71: ...t signal Bit Name Description 0 Reserved May contain 0 or 1 1 Position wraparound Set when the encoder position exceeds 2 147 483 647h the most positive position and wraps to 2 147 483 647h the most negative position or vice versa 2 Reserved May contain 0 or 1 3 Capture received Set when the Index position capture hardware acquires a new position value 4 Motion error Set when the encoder position ...

Page 72: ...owing additional captures to occur While this bit is set no new values will be captured 10 In motion indicator Set 1 when the profile generator commanded position is changing Cleared 0 when the commanded position is not changing 11 15 Reserved May contain 0 or 1 Bit Name Description 0 Calibration completed Set 1 when an analog input calibration procedure is completed Cleared if not completed 1 In ...

Page 73: ...ion 12 1 5 1 Signal Sense Mask The bits in the Signal Status register represent the high low state of various signal pins It is possible to invert the incoming signal to match the signal interpretation of the user s hardware Bit Name Description 0 Overcurrent Set 1 to indicate a fault due to a short circuit or overload in the drive output 1 4 Reserved May contain 0 or 1 5 Overvoltage Set 1 to indi...

Page 74: ...The following table lists each of the event conditions that Juno monitors along with the default event actions that will occur if no user specified event actions are provided Bit Name Interpretation 0 A encoder Set 1 to invert quadrature A input signal Clear 0 for no inversion 1 B encoder Set 1 to invert quadrature B input signal Clear 0 for no inversion 2 Index encoder Set 1 to invert clear 0 for...

Page 75: ...lies on the FaultOut signal to indicate a fault condition After the FaultOut signal goes active external logic must delay a minimum of 150 μSec but thereafter may request that Juno Overcurrent Disable Motor Output Occurs when an overcurrent condition is detected The programmed event action must be Disable Motor Output or Brake Overvoltage Disable Motor Output Occurs when an overvoltage condition i...

Page 76: ...arly to FaultOut but provides a separate programmable mask Any or all of Event Status register bits may be programmed to cause an interrupt If a 1 is stored in the mask then a 1 in the corresponding bit of the Event Status register will cause an interrupt to occur Juno continually and simultaneously scans the Event Status register and interrupt mask to determine if an interrupt has occurred When a...

Page 77: ...t signal active Event action process ing SetEventAction Two parameter command The first is a fixed value that specifies the event condition for which an action is being defined the second is a fixed value defining the action Juno defines 10 separate event conditions and therefore this command could be called up to 10 times one for each condition Event recovery method SetDriveFaultParameter Two par...

Page 78: ...Motion Monitoring Control 78 Juno Step Motor Control IC User Guide 12 This page intentionally left blank ...

Page 79: ...oltage decreasing voltage decreases with increasing temperature thermistors are supported For voltage increasing thermistors 0 0V represents the lowest possible temperature and for voltage decreasing thermistors 3 3V represents the lowest possible temperature The overtemperature threshold is user programmable The sign of the overtemperature threshold selects whether the Temperature input increases...

Page 80: ...nalog conditioning circuitry determine the overall current range that can be measured For the DC bus supply current input this range should be at least 150 of the maximum expected DC bus peak current flow The measured bus supply current is an unsigned number with range of 0 to 65 535 The user specified DC bus supply overcurrent threshold is continuously compared against the measured current The DC...

Page 81: ...sent 3 3V at the BusVoltage input when the DC bus voltage is 65 volts The scaling is 65V 65 536 or 992 mV count To set an undervoltage threshold of 45V a value of 45 000 mV 992 mV count 45 362 is specified To set an overvoltage threshold of 52V a value of 52 000 mV 992 mV count 52 419 is specified The under and overvoltage thresholds function continuously To disable the under voltage or over volta...

Page 82: ...ergy limit would be set to Energy Limit peak current2 continuous current limit2 time Energy Limit 52 A2 32 A2 2 Sec Energy Limit 32A2 Sec Following the current scaling example in Section 9 2 2 Current Signal Scaling the programmed continuous current limit would be 3 0 A 625 32 767 10 0A 6 144 The programmed energy limit value must convert seconds to Juno current loop cycles 19 531 cycles sec and m...

Page 83: ...e sec ond has a range of 0 to 65 534 and specifies the DC bus supply overcurrent threshold A value of 65 534 disables this feature DC bus overcurrent return threshold SetDriveFaultParameter Two parameter command The first must be 11 the sec ond has a range of 0 to 65 534 and specifies the DC bus return overcurrent threshold A value of 65 534 disables this feature DC bus overvoltage threshold SetDr...

Page 84: ...ly consists of a sense resistor as shown in Figure 13 3 or a linear Hall sensor The analog processing circuitry required for each is somewhat different If a dropping resistor is used an isolating operational amplifier current mirror or similar circuit should be used Linear Hall sensors typically use just a ground referenced operational amplifier The BusCurrentSupply input range is 0 0V to 3 3V wit...

Page 85: ...efore a low pass filter with a rolloff of 10 kHz or less is recommended Figure 13 6 shows a typical processing circuit for DC Bus voltage monitoring The bus voltage sensing consists of R2 R4 and C1 R2 and R4 scale the bus voltage between 0 and 3 3V C1 is referenced to analog ground and should be placed close to the BusVoltage pin See Section 15 6 Drive Related Safety and Monitoring Features for co...

Page 86: ...Drive DC Bus Safety 86 Juno Step Motor Control IC User Guide 13 This page intentionally left blank ...

Page 87: ...is and begins executing these commands Note that processing stored commands may increase the overall initialization time depending on the command sequence stored 14 2 NVRAM Juno step motor control ICs provide a 1 024 16 bit word NVRAM The primary purpose of the NVRAM is to allow configuration information to be stored so that upon power up the Juno IC can be configured and initialized automatically...

Page 88: ...nds refer to the Juno Velocity Torque Control IC Programming Reference 14 5 Signal Processing 14 5 1 Output Signal Status During Power up The following table summarizes the Juno step motor control IC output signal states during power up and after power up when no initialization data is stored in the NVRAM Parameter Host Command Mnemonic Range Description Initialization control settings ExecutionCo...

Page 89: ...ed in this circuit external control of the Reset signal is not required since the Juno IC will trigger an internal reset upon power up The Reset pin is driven low by Juno under a power on or reset condition If external reset is implemented an open drain device is used If no external reset is implemented Q1 from the above circuit is eliminated If configuration data has been stored in the NVRAM then...

Page 90: ...Power up Configuration Storage NVRAM 90 Juno Step Motor Control IC User Guide 14 This page intentionally left blank ...

Page 91: ...erenced by the name corresponding to the specified functionality For example pin 56 on the MC74113 is named PWMHighA PWMMagA but will be referenced by the name PW MHighA in the PWM High Low motor drive schematic example and PWMMagA in the sign magnitude motor drive schematic example 15 1 1 Interfacing to Other Logic Families When integrating different logic families consideration should be given t...

Page 92: ...es under different conditions are provided for thermal design θJA is the junction to ambient thermal resistance Although it is an important design reference this thermal metric highly depends on the board design and system configurations Directly using it for junction temperature estimation could result in misleading results because the environmental factors are different from design to design ψjT...

Page 93: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 93 15 This page intentionally left blank ...

Page 94: ...nalog 3 3Vs is the main digital supply for the MC74113 and MC75113 devices 3 3V_Analog is the filtered version of the 3 3Vs supply for ADC and its related conditioning circuitry The extra filtering is used to provide additional decoupling of the analog elements from the digital elements in the circuitry Notes The power supplies schematic provided in Figure 15 1 is for reference only and is designe...

Page 95: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 95 15 Figure 15 1 Basics Power Supplies MC74113 and MC75113 ...

Page 96: ...hough in some of the schematics that follow these capacitors are not shown for reasons of brevity In some cases especially for analog processing circuitry it may be beneficial to run a separate power line from the power supply to the component in order to prevent power supply fluctuations from impacting low level signal components The same points should be considered when designing the ground A go...

Page 97: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 97 15 Figure 15 2 Basics Clockand Bypass Caps MC74113 and MC75113 ...

Page 98: ...o drive this pin to assert a device reset In this case it is recommended that this pin be driven by an open drain device All digital output signals have an internal pullup except for FaultOut and the PWM signals See Section 14 5 1 Output Signal Status During Power up for more information If the AmplifierEnable and FaultOut signals are used they should have an external pull down resistor to prevent...

Page 99: ...und while C3 is to analog ground An optional resistor can be put between R5 and C3 to improve noise immunity as R10 does for temperature sensing function This block is also a low pass filter with bandwidth of 1 5kHz This bandwidth should be selected to respond to real voltage fault event while attenuating bus noise U1 is the high side bus current sensing IC With current sensing resistor R1 at 10mO...

Page 100: ...Application Notes MC74113 MC75113 100 Juno Step Motor Control IC User Guide 15 Figure 15 3 Drive Safety and Monitoring ...

Page 101: ...across R2 which is the differential voltage It also attenuates the common mode noise including the noise on the power train D1 provide a 1 65V voltage bias source as half the 3 3V ADC range This bias can be shared with current sensing stages of other phases With this voltage bias R2 current is sensed in either direction By default the MC74113 and MC75113 take 1 65V reading as zero current Host com...

Page 102: ...istor can be sized accordingly The board layout is critical for an optimal current sensing signal The current sensing traces to R3 R5 should be separated from the power path through R2 and these two traces should be routed in pair to improve its common mode noise immunity Also a motor power train has multiple current sensing resistors and these resistors are referred to ground During layout please...

Page 103: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 103 15 Figure 15 4 Leg Current Sensing ...

Page 104: ...ent and its voltage rating should be chosen based on HV and the 15V R21 is optional it can limit the charging current especially during power up when C6 is zero voltage R1 R3 and D1 provide an unsymmetrical turn on and turn off capability Upon power up or during reset PWMHighA and PWMLowA output are high impedance Therefore pull down resistors R24 and pull up resistor R22 ensure that the upper and...

Page 105: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 105 15 Figure 15 5 Step Motor Drive with 2A Continuous Current Rating ...

Page 106: ... the 12V R3 is optional it can limit the charging current especially during power up when C3 is zero voltage R1 R4 and D2 provide an unsymmetrical turn on and turn off capability Upon power up or during reset PWMHighA and PWMLowA output are high impedance Therefore pull down resistors R13 R14 ensure that the upper and lower switches are all off so that the half bridge output is high impedance Also...

Page 107: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 107 15 Figure 15 6 Step Motor Drive with 5A Continuous Current Rating ...

Page 108: ...hing diode with low leakage current and its voltage rating should be chosen based on HV and the 15V R21 is optional it can limit the charging current especially during power up when C6 is zero voltage R1 R3 and D1 provide an unsymmetrical turn on and turn off capability Upon power up or during reset PWMHighA and PWMLowA output are high impedance Therefore pull down resistors R24 and pull up resist...

Page 109: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 109 15 Figure 15 7 Step Motor Drive with 10A Continuous Current Rating ...

Page 110: ...inputs are filtered version of the PWM signal In the example a first order RC filter is used with bandwidth of 1 42kHz with gain of 35dB at 80kHz R3 and R4 should be 1 or better C7 and C8 should be NP0 type with 5 or better The bandwidth of the low pass filter should be able to attenuate the PWM frequency component because a higher cut off frequency results in higher ripple However the signal dela...

Page 111: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 111 15 Figure 15 8 Step Motor Control with Sign Magnitude Signal ...

Page 112: ... MC58000 Electrical Specifications 15 8 1 MC75113N Axis 1 For Axis 1 the MC75113N receives Pulse Direction and AtRest from Magellan and controls the motor with PWM high low and leg current sensing Please refer to Section 15 7 3 Step Motor Drive with 5A Current Rating for more details 15 8 2 MC74113N Axis 2 For Axis 2 the MC74113N receives Pulse Direction and AtRest from Magellan and controls the m...

Page 113: ...Application Notes MC74113 MC75113 Juno Step Motor Control IC User Guide 113 15 Figure 15 9 Two Axis Step Motor Drive With Multi Axis Magellan ...

Page 114: ...Application Notes MC74113 MC75113 114 MC58113 Electrical Specifications 15 This page intentionally left blank ...

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