Innovative Motion
Control Solutions
SPS, Nov. 2013
November 2013
Agenda
10:00 – 10:05 Gathering & seminar introduction (Z'eev)
10:05 – 10:30 450mm wafer handling (Z'eev)
10:30 – 11:15 Look-ahead algorithm, G&M-codes,
Network cable failure detection & recovery (Shura)
11:15 – 11:30 Break
11:30 – 12:15 Motion enhancements new features (Boaz)
12:15 – 13:00 Motion enhancements new features-cont. (Maksim)
2
450mm Wafer Handling
and Inspection
3
State of the Art Motion Control Solutions
450mm (& 300mm) Wafer Inspection
4
Agenda
> 450mm wafer inspection challenges and general motion
system structure
> System/subsystem motion control requirements
> ACS technologies and solutions to meet specific requirements
> Complete solution summary
5
Challenges in 450mm Wafer
Production / Inspection
> Larger work envelope, higher speeds and larger masses
> Equal or better level of precision and accuracy!
Extremetech.com
6
Wikipedia.com
Motion System Structure
>
High precision wafer positioning stage
> Gantry (XX’Y) structures preferred over basic XY
> Higher performance
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stand-still jitter and better constant velocity
High resolution laser based encoders or interferometers
May require multiple feedbacks with real-time feedback switching
Control algorithms become more complex (servo, homing, etc.)
Inspection heads
> Relatively small linear/rotary motors (brushless, brush, or stepper)
> Digital and Analog I/O
> Synchronization with motion (camera, laser, etc.)
>
Auxiliary axes and I/Os
> Transport/handling, alignment, optics focus
> Safety interlocks, GP digital/analog I/O
>
7
User interface & high level machine control typically resides on PC
Wafer Stage
Motion Control Requirements
> Large Gantry – 750 x 750 mm or more travel area
> Typical Motion Performance Specs
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High speed >1 m/sec
High accuracy <50nm over 450mm
Fastest possible Move & Settle to ±1nm window
Smooth velocity
(±3nm following error @ 100mm/sec)
> Typical Stage Components
> Air or precision mechanical bearing
> Linear servomotors
> High resolution optical and/or laser interferometer and
laser encoder
8
Inspection Heads
Motion Control Requirements
Dynamic Z auto-focus
Multiple low power motors and feedback types
Camera/Optic triggering based on XY or XYZ position
Focus accuracy of 100nm
Automatic, smooth switching to & from focus error sensor
and position encoder feedback
> Mount driver and I/O on moving heads to simplify cabling
cables
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Auxiliary Axes & I/O
Motion Control Requirements
> Multiple motor and feedback types, wide range of power
levels
> Wide range of I/O types, fast response time (=sub-millisecond)
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Wafer Stage Subsystem
Control Solution
> MC4Unt integrated multi-axis drive chassis
> Includes
› Controller & EtherCAT master
› Modular drives
› Power supply
> Revolutionary NanoPWMTM drives offer performance better
than linear drives
> MIMO gantry control
> Advanced ServoBoostTM algorithm for optimal
performance and stability
> Additional advanced features
› 2D/3D Error Mapping
› Profile Shaping
› Kinematics transformations
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MC4UNT Complete System
Motion and Machine Controllers
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SPiiPlus EtherCAT Motion and Machine Controller
Up to 32 (64) synchronized axes & 1000’s I/Os
Multitasking with 64 threads / programs
Flexible programming
> Real time ACSPL+
> IEC61131-3 PLC
> Host libraries
> Other possible controllers
> SPiiPlusSC PC based Soft Controller
> SPiiPlusNTM standalone controller
12
NanoPWMTM Drives
Better than Linear Drives
> Based on ACS’ proprietary
PWMBoostTM technology
developed over the last 5 years
> Replaces linear drives, providing:
> Better performance
> Sub-nano jitter
> Smooth velocity (velocity
error<<1%)
> Higher voltages and higher
currents
13
±0.4nm
jitter
1nm
steps
NanoPWMTM Drives
Better than Linear Drives
> A much smaller package
> Improved reliability
> Better price
14
Wafer Stage Control Technology
ServoBoostTM
> ServoBoostTM is a proprietary real time servo algorithm
that:
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>
>
>
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Identifies disturbances in real time
Analyzes disturbance root cause
Compensates for it and attenuates its impact
Predicts the disturbances anticipated and prevents their negative effects
ServoBoostTM provides:
> Improved machine performance: Faster settling, better stability, lower jitter,
smoother velocity
> Excellent robustness
› Large changes in load
› Varying system parameters
> Automatic compensation of disturbances, resonances, axes interaction,
cogging and more
15
Inspection Heads Subsystem
Control Solution
> UDMLC – 2 , 4-axis compact EtherCAT drive
module for small motors
> Designed for remote mounting (100x75x48mm3)
> 12 to 48Vdc, 1.25/2.5A, 2.5/5A, 5/10A per axis (dual
axis)
> Brush, brushless, stepper, voice coil motors
> Incremental and absolute digital encoders
> Autofocus control algorithm
> Multiple GP I/Os
> IOMNT
> Compact (101x65x59mm3)
> Up to 32/32 I/O per module
> 24Vdc, 0.5A per output
16
Inspection Head Control Technology
Autofocus
> Proprietary autofocus algorithm developed for wafer inspection
> On the fly switching between multiple feedback sources
> Maintain focus accuracy while moving (high bandwidth)
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Auxiliary Subsystem Axes & I/O
> UDMxx – Multi-axis EtherCAT drive
modules for various motor sizes
>
>
>
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Wide power ranges (100W to 3kW peak)
Brush, brushless, stepper, voice coil motors
Incremental, absolute digital, SinCos encoders
Multiple GP I/Os
> IOMNT (if additional I/O needed)
> EtherCAT modules for interfacing to
standard drives
> UDIxx - +/-10V commands, encoder inputs
> PDMnt - Step/Dir stepper and servo drives
> 3rd Party EtherCAT drives and I/O
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A Complete Control Solution
for Wafer Inspection
MC4U EC
Master
with
NanoPWM
Drives
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Additional
optional drives
and I/O
3-8
Wafer Stage
UDMLC
IOMNT
32/32
4
Inspection Heads
UDMXX
2
IOMNT
32/32
Auxiliary Axes & I/O
Summary
> Highest Performance
> Advanced algorithms ServoBoost, MIMO Gantry, Autofocus, feedbacks switching
> NanoPWM drives to handle larger loads with higher dynamics needs
> Scalability & Flexibility
> Standard Industrial EtherCAT Network
> 64 axes & 1000’s of I/Os
> Support of 3rd party devices
> Short time to market
> One common platform for many machines and system configurations
> Single development environment for entire system with full simulator
> Suitable for many other demanding applications
> Electronic Mfg Pick/Place, Flat Panel Display Inspection, Wide Format Inkjet
Printing, SEM, CMM
20
Look-Ahead Algorithm
G&M-Codes Programming Support
Network Cable Failure Detection & Recovery
21
Look-ahead in SPiiPlusNT
Agenda
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Market needs
Look-ahead advantages
SPiiPlusNT XSEG capabilities
Corner processing
Example
Further XSEG extensions
Look-ahead in SPiiPlusNT
Market Needs
> Markets:
> Cutting applications (especially laser cutting)
> High-speed precise machining
> Applications that challenge to perform a process more
efficiently and with better quality
> Technically, it means to pass trajectory with higher velocity
and smaller tracking (position) error
23
Look-ahead Advantage
> Look-ahead is an ability of the motion controller to detect
conditions that cause exceeding of the machine limits and
correct the motion profile automatically and in advance
> Thus, with Look-ahead algorithm better performance and
accuracy of the trajectory following is achieved
24
Look-ahead Algorithm
in SPiiPlusNT
> Look-ahead algorithm in SPiiPlusNT is implemented as part of
the new segmented motion - XSEG
> Main capabilities of XSEG:
• Automatic detection of corners and segments, where
required velocity exceeds axis limits (maximal acceleration,
jerk)
• Automatic velocity reduction at such segments
• Building-up velocity profile using multi-segment look-ahead
algorithm
• Segments adding “on-the-fly” (competitive advantage)
• Velocity override (competitive advantage)
• Outputs synchronization (competitive advantage)
25
Corner Processing
> The controller automatically detects the corner and can
automatically calculate the corner velocity in order to pass it
with no acceleration/jerk jumps
> As alternative option, the corner velocity can be set by the
application
Exact path option
Corner angle
Required velocity
Velocity profile
Corner
Path
Corner
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Corner velocity
Corner Processing
Scope Graph
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XSEG- Further Extensions
> Different geometry processing
> Smooth path with permitted deviation/curvature
> Smooth path with minimal velocity
> 3D segments
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RS274 Numerical Control Language (G-code)
Agenda
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Market needs
Implementation
Execution
Integration with ACSPL+
G-code
Market Needs
> Market Needs:
> G&M-codes language is the de-facto standard for CNC
machines
> CAD/CAM systems produce G&M-codes programs for
many other markets, such as
› cutting applications
› different high-speed precise machining
30
G-code in SPiiPlusNT
> SPiiPlusNT implements many common G&M codes,
specifically motion-related commands, tool and offset
compensation commands, absolute/increment programming,
digital outputs control, etc.
Main advantages:
> Sophisticated look-ahead algorithm for segments
processing
> Outputs synchronization with the motion
> Integration of G-code program with ACSPL+
> Ability to implement unknown G-codes by the user
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G-code Program Execution
> Editing, debugging and execution of G-code program is done
the same way as ACSPL+ program
SPiiPlusNT controller
CAD/CAM SW
G-code program as text file
N10 G0 X-90 Y-100
N15 G2 X-100 Y-90 I-90 J-90
N20 G1 Y90
N25 G2 X-90 Y100 I-90 J90
N30 G1 X90
N35 G2 X100 Y90 I90 J90
N40 G1 Y-90
N45 G2 X90 Y-100 I90 J-90
N50 G1 X-90
N60 G0 X0 Y0
N100 M2
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ACSPL+ buffer
G-code program is
downloaded to the
controller either by
SPiiPlus MMI or by
the user program
N10 G0 X-90 Y-100
N15 G2 X-100 Y-90 I-90 J-90
N20 G1 Y90
N25 G2 X-90 Y100 I-90 J90
N30 G1 X90
N35 G2 X100 Y90 I90 J90
N40 G1 Y-90
N45 G2 X90 Y-100 I90 J-90
N50 G1 X-90
N60 G0 X0 Y0
N100 M2
G-code with ACSPL+
> ACSPL+ commands and G-code commands can be mixed
within the controller buffer
CAD/CAM SW
SPiiPlusNT controller
G-code program as text file
N10 G0 X-90 Y-100
N15 G2 X-100 Y-90 I-90 J-90
N20 G1 Y90
N25 G2 X-90 Y100 I-90 J90
N30 G1 X90
N35 G2 X100 Y90 I90 J90
N40 G1 Y-90
N45 G2 X90 Y-100 I90 J-90
N50 G1 X-90
N60 G0 X0 Y0
N100 M2
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G-code program is
downloaded to the
controller either by
SPiiPlus MMI or by
the user program
ACSPL+ buffer
N10 G0 X-90 Y-100
N15 G2 X-100 Y-90 I-90 J-90
N20 G1 Y90
N25 G2 X-90 Y100 I-90 J90
N30 G1 X90
N35 G2 X100 Y90 I90 J90
OUT0.0=1 ! ACSPL+ line
N40 G1 Y-90
N45 G2 X90 Y-100 I90 J-90
N50 G1 X-90
N60 G0 X0 Y0
N100 M2
Implementing G-code Commands
by the User
> Unknown G-code commands support can be easily added by
implementing G-code subroutine
CAD/CAM SW
SPiiPlusNT controller
ACSPL+ buffer
G-code program as text file
N10 G0 X-90 Y-100
N11 G54
N15 G2 X-100 Y-90 I-90 J-90
N20 G1 Y90
N25 G2 X-90 Y100 I-90 J90
N30 G1 X90
N35 G2 X100 Y90 I90 J90
N40 G1 Y-90
N45 G2 X90 Y-100 I90 J-90
N50 G1 X-90
N60 G0 X0 Y0
N100 M2
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G-code program is
downloaded to the
controller either by
SPiiPlus MMI or by
the user program
N10 G0 X-90 Y-100
N11 G54
N15 G2 X-100 Y-90 I-90 J-90
N20 G1 Y90
N25 G2 X-90 Y100 I-90 J90
N30 G1 X90
N35 G2 X100 Y90 I90 J90
N40 G1 Y-90
N45 G2 X90 Y-100 I90 J-90
N50 G1 X-90
N60 G0 X0 Y0
N100 M2
D-buffer
G54:
N10 G10 X10 Y20 Z30
RET
Unknown G-code
command
implementation
Network Cable Failure
Detection & Recovery
Agenda
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Demonstration movie
Advantages
Prerequisites
Functionality
Network Cable Failure Detection
& Recovery - Demonstration
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Network Cable Failure Detection
& Recovery - Advantages
> In case of cable or connector failure:
> the machine can be immediately recovered without a need
to repair the broken part
> the location of broken cable or connector is detected by the
controller that simplifies the machine repair
37
Network Cable Failure Detection
& Recovery - Prerequisites
> In order to support Enhanced Network Failure and Recovery,
the machine setup should provide:
> Additional (2nd) EtherCAT port in the EtherCAT Master
module
> Additional cable that connect the 2nd EtherCAT port to the
network
> Currently, only SPiiPlusSC with two EtherCAT ports can be
used as EtherCAT Master
> In the future also SPiiPlusNTM and MC4U with 2nd EtherCAT
port will be available
38
Network Cable Failure Detection
& Recovery - Functionality
> Detection of the location of the failure
> The system reactivation in the simple and quick way, with no
need for the machine re-initialization
> Ability to save the configuration after the failure, so at the
subsequent power-up, the system will be initialized correctly
(even if the cable is still broken)
> Quick and simple way to reinitialize the network after the
failure repair
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New Servo & Motion Features
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Agenda
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ServoBoostTM – for enhancement of servo performance
Cogging compensation – for smoother motion
Profile shaping – for reduction of vibrations
Smooth Feedback switching – for systems with multiple feedback
devices
Enhanced fast Sin-Cos – for high resolution Sin-Cos encoders, up to
6[MHz]
MotionBoostTM – for faster motion
One parameter tuning – for simpler high performance servo tuning
BiQuad filters – for solving resonance issues
NanoPWMTM – for ultimate jitter performance
ServoBoostTM
Better Servo Performance
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>
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ServoBoostTM is a real time algorithm that:
> Identifies disturbances in real time
> Analyzes disturbance root cause
> Compensates it and attenuates its impact
ServoBoostTM provides:
> Improved machine performance: Faster settling, better stability,
lower jitter, better constant velocity
> Automatic adaptation to large changes in load and system
parameters
> Automatic compensation of disturbances, resonances, axes
interaction, cogging and more
Applicable to all ACS high performance (HP) products
Adaptation to Load Changes
• System performance may deteriorate
or even become unstable due to
significant load changes.
• With ServoBoostTM , the performance
remains consistent and stable despite
of load changes and disturbances.
Position error with PID control
Position error with ServoBoostTM
Total moving mass is increased x 3
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No load
Adaptation to Increasing Load by x3
Initial system
With extra load
Standard PID
With extra load
Using ServoBoostTM
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> With standard PID algorithm
> The system is still stable
> The bandwidth is 3 times smaller
(20Hz instead of 60Hz)
> Poor performance
> With ServoBoostTM
> maintains the 60Hz bandwidth
> Same performance
> It also compensates the resonance
created by the elevated center of
gravity
Crossover Error EliminationSeveral Axes, One Machine Frame
Position Error 5[nm/div]
> Due to reaction forces of
accelerating axes the frame
vibrates and deteriorates
overall performance. Appears
in almost all multi axes
machines.
> ServoBoostTM eliminates
this interaction, enhancing
placement accuracy
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Without ServoBoostTM
With ServoBoostTM
Automatic Cogging Compensation
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Cogging and Periodic Disturbances
> Brushless motors may suffer from periodic disturbances that
result from imperfections in motor structure or electrical drive.
> These disturbances create speed fluctuations, vibrations,
acoustic noise, and an excitation of lightly damped resonances.
> Cogging is an example of a periodic disturbance: non-uniform
force that is caused by magnetic interactions between magnets
and the rotor slots in the motor.
> Motors with low cogging are usually more expensive.
47
Cogging and Periodic Disturbances
> Cogging Compensation algorithm compensates cogging
automatically and provides an “electronic upgrade” to
inexpensive motors.
> ServoBoostTM provides automatic compensation to cogging
and other periodic disturbances.
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Profile Shaping
> If a first impulse starts a vibration, a second impulse can
cancel it.
> Timing and magnitude of the second impulse must be
accurate.
> Additional pulses may be added to improve robustness.
> Several vibration modes can be treated.
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Profile Shaping
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Switching between Multiple Feedback Devices
> In systems with more than one feedback device, it’s
possible that some of the feedbacks do not cover the entire
travel range
> Maximal length of glass scales/ laser interferometer
mirrors is limited and insufficient for some applications
> Encoders with multiple short glass scales can be less costly
than one long scale encoder
> In moving magnet applications the encoder scale may be
attached to the moving magnet, that moves through
multiple encoder readheads
51
Multiple Encoder Scales Switching
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Multiple Encoder Scales Switching
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Fast
Switching
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&
Smooth switching
Fast Sin-Cos Support
> Improved support has been developed for high resolution
Sin-Cos feedbacks
Old support
New support
Sine periods/sec
2.5x106
6x106
Suitable for high resolution feedback
With restrictions Yes
Suitable for PWM drives
No
> Available for UDMNT, UDIHP
> Soon available for MC4U
54
Yes
MotionBoostTM – Solution for
Fast & Aggressive Motion
> MotionBoostTM technology implements an enhanced motion
profile
> Designed to :
> Improve settling time by reducing the residual vibrations
> Lower peak current, acceleration and velocity values
> Mostly effective in short aggressive moves with aggressive
servo
> Ideal for Pick and Place applications and wire bonders
> Very short move durations are possible with SPiiPlusSC using
CTIME = 0.2[msec]
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MotionBoostTM Example
10[mm] motion in 58[msec]
Regular PTP
Move and settle to 1[µm] 170[msec]
MotionBoostTM
84[msec]
~50% improvement
of move and settle
Position error with PTP
5[µm] div
1[µm] div
Zoom In
Position error with Motion Boost
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Simplified Tuning for
High Performance
> One parameter tuning of position and velocity loops
> The user:
› Specifies the desired bandwidth of the system
> The tool:
› Identifies the characteristics of the system
› Automatically calculates the servo parameters
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Easy Interface & Reliable Result
•
Tuning example:
Tuning is based on a single
parameter: system bandwidth
Resulted FRF
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Inertia Mismatch
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Inertia Mismatch Compensation
> Stability issues may occur when a heavy load is connected to
relatively low-inertia motor Inertia motor through a
compliant transmission
> At low frequencies the system behaves as a rigidly coupled
motor and load
> At high frequencies the load is effectively decoupled from
the motor. The gain of the plant significantly increases and
reflects the motor inertia only
60
High Order BiQuad Filters – for Inertia
Mismatch Compensation
> ACS offers fully adjustable high order BiQuads filters in the
servo loops.
> Examples where BiQuads can be handy:
> Inertia mismatch compensation
> Frame vibration compensation
> Attenuation of resonances
61
BiQuad Filters– Inertia Mismatch
Compensation
> Example: Cardiac CT scanner
> Rotation motor connected by a belt to the load
> Inertia mismatch of 10,000!
Decoupling of load raises
the plant gain
Rigidly coupled motor and load
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BiQuad Filters– Inertia Mismatch
Compensation
> Using a regular PID results in a very low bandwidth with
poor stability margins.
Sub-Hertz Bandwidth
Poor Stability margins
causes high resonance
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BiQuad Filters– Inertia Mismatch
Compensation
> A proper selection of Biquad filters results in a high
bandwidth with significantly improved stability margins
~30Hz Bandwidth
Sufficient
Stability margins
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NanoPWM™ Drives
NanoPWMTM Drive Technology is a brand new state of the art
proprietary PWM power stage implementation in select ACS drives, that
provides:
> As good or better performance than precision linear drives
> Sub-nano jitter
> Smooth velocity (velocity error<<1%)
>
>
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Higher voltages and higher currents in a much smaller and cost
effective package when compared with commercially available
linear drives
Improved reliability over linear drives
NanoPWM™ - Compact Solution
>
Simpler to use:
> Integrated into MC4U control module
for full hardware multi-axis systems
solution
> Single bus supply vs. bipolar
supplies in most linear drives
> Digitally adjustable advanced
current loop vs. primitive
non-adjustable analog loops
in most linear drives
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NanoPWM™ Drives
> Ultimate solution for:
> 450mm / 300mm wafer handling and inspection stages
> FPD handling and inspection
> Demanding applications that require high performance
> High power output & compact footprint
> 100Vdc, up to 15A/30A (continuous / peak)
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NanoPWM™ Technology
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>
Sub-nanometer position jitter performance
Nanometer stepping:
±0.4nm
jitter
1nm
steps
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Significantly Lower Standstill Jitter
comparing to equivalent 3rd party linear drives
Stand still jitter[nm] p-p
3rd party linear drive
NanoPWMTM drive
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NanoPWMTM
(100V, 30Apeak)
3rd party linear drive
(±50V, 30Apeak )
1.32
3.56
Better Results at Low Speed
comparing to off-the-shelf linear drives
Position Error[nm] p-p
@ 1[mm/sec]
NanoPWMTM
3rd party linear drive
22.3
47.8
3rd party linear drive
NanoPWMTM drive
(*) Results taken on an ironless
linear stage with cross roller
bearings
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NanoPWM™ is Superior to Any Other Equivalent
PWM Drive in the Market
Stand still jitter[nm] p-p
Regular PWM drive
NanoPWMTM drive
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NanoPWMTM
100V, 30[A]
Standard PWM
100V, 30[A]
1.4
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NanoPWM™
the Best PWM Drive One Can Get!
NanoPWMTM
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3rd party linear drive
Package size
Small
Big
Complexity
Low
High
Performance
Very Good
Good
Reliability
Very Good
Problematic
Price
Lower
High
Summary
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>
Algorithms for better system performance were discussed–
ServoBoostTM, MotionBoostTM, Cogging compensation, profile
shaping and BiQuad filters
>
New developments were presented:
> Enhanced support for fast Sin-Cos
> Support for switching between multiple feedback devices
> New tool for advanced and simpler tuning
> NanoPWMTM drives – for ultimate jitter performance, better
than cumbersome linear drives
THANK YOU