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ADI | Engineering a More Sustainable Future
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DrIVING HIGHer LeVeLS OF FLexIBILITy, PrODuCTIVITy, AND SuSTAINABILITy IN SMArT MANuFACTurING
Intelligent Motion Control Solutions
Analog Devices technologies and system-level solutions for intelligent motion
applications are enabling higher levels of performance while reducing energy
consumption and downtime. Figure 5 outlines a typical motor drive signal
chain that comprises six key blocks. Each block outlines an ADI solution.
Power Electronics
Power electronics provide the power conversion in a motor drive system. For
high voltage systems
(
>100 V
)
, an isolated gate driver is used to drive the power
semiconductors. ADuM4122 is a single-gate isolated gate driver with 3 A short
circuit
(
<3 Ω
)
. It supports functional or reinforced isolation up to ~800 V DC bus
with slew rate control for EMI/power loss optimization. It also supports high
common-mode transient immunity
(
CMTI
)
and low propagation delay for use
with SiC and GaN power semiconductors. ADuM160N multichannel digital isola-
tors can be used to isolate PWM signals for use with integrated power modules
(
IPM
)
that integrate the gate driver with the power semiconductor. The ADuM6028
isolated power device can be used in conjunction with digital isolators, isolated
transceivers, and isolated data converters to provide a very small 8-lead solution
that is fully safety certified and ready to use.
For low voltage systems
(
<100 V
)
, the LTC7060, a 100 V half-bridge driver with
floating grounds and programmable dead time or the LTC7000, a 150 V protected
high-side NMOS static switch driver with PassThru
™
technology and adaptive shoot-
through protection can be used to drive low voltage semiconductors. LTC7000
also supports programmable dead time for efficiency optimization, enhanced
current control, and slew rate control for EMI reduction.
Current Sense
For isolated current sense measurement, the ADuM7701 is a high performance,
second-order, sigma-delta
(
∑
-Δ
)
modulator that converts an analog input signal
into a high speed, single-bit data stream with on-chip digital isolation based
on Analog Devices iCoupler
®
technology. ADuM7703's low offset drift
(
0.6 μV/°C
max
)
reduces torque ripple and is packaged in a compact 8-lead package with
integrated LDO to simplify power supply design and reduce board area. Its 150 V/ns
min CMTI rating enables use with GaN and SiC power electronics.
AD8410 high voltage, current sense amplifiers provide a high gain
(
20 V/V, 50 V/V,
100 V/V
)
and low offset drift
(
~1 μV/°C
)
with high bandwidth
(
2 MHz
)
for optimum
current control. AD8410 also includes bidirectional current measurement input up to
100 V common-mode input. The LTC6102 precision zero-drift current sense amplifier
ensures accuracy across a wide range of operating conditions and can be powered
from high-side voltages up to 100 V in shunt-based current sensing applications.
Position Sense
Position feedback is used for direct position control or for inferring rotational
speed and implementing machine speed control. ADA4570 and ADA4571 integrated
AMR angle sensors with integrated signal conditioners enable higher absolute
accuracy position sensing for motor drive and servo applications
(
<0.1° error,
<0.5° over life/temperature
)
. They are robust in magnetically harsh environ-
ments, support wide air gap tolerances without degradation of angular error
(
unlike Hall/GMR/TMR
)
, and simplify system design considerations. The ADA4570
and ADA4571 are not affected by dust or dirt when compared with optical sensors
in industrial applications, and they have very low latency compared to digital out-
put solutions on the market with built-in calibration engines. ADA4571 produces
two single-ended analog outputs
(
sine and cosine
)
that indicate the angular
position of the surrounding magnetic field, while the ADA4570 produces two
differential analog output pairs. A dual version of the ADA4571
(
ADA4571-2
)
is also
available where full redundancy is needed in safety critical applications.
The AD7380 is a 4 MSPS dual simultaneous sampling, 16-bit SAR ADC that provides
precision, throughput, and minimal size for encoder applications. AD7380 is in a
small package size
(
3 mm × 3 mm
)
for miniaturization of the encoder with 4 MSPS
throughput for minimal latency and fast control loop transient response. The AD7380
oversampling engine allows higher accuracy for slower operating conditions.
Figure 5. Analog Devices solutions for intelligent motion applications.
Power Electronics
Current Sense
∑-
∆
∑-
∆
Position Sense
Machine Health
AC
Motor
ADC
+ – + –
Current Feedback
PWM
Output
Network
Switch
Isolated Gate Drivers
LV Bridge Drivers
Robust Isolation
Technology
Current Feedback for
Precision Motion Control
Power Management
Multi-Axis and Network Connectivity
Position Feedback for
Precision Motion Control
ESD Protected Isolated/
Nonisolated RS-485/RS-422
AMR Angle Sensing
Machine
Monitoring
Network
Interface
PHY
V
o
LDO
V
i
PHY
Position Feedback
ADC
ASIC
Motion Controller
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