Transcript Power Forum: An Avnet Virtual Conference

STEPPER MOTOR DRIVER
SOLUTIONS
Jon Chen
Applications Engineer
Introduction
Purpose
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To introduce ROHM’s line of stepper motor drivers
Objectives
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To provide an overview of the product offering
To discuss the focus of product development efforts
To highlight the features/functionality of ROHM’s stepper motor drivers
and their advantages
To introduce examples of common applications
To discuss available design resources
Common Applications
Printer / Copier (Paper Feed)
Scanner
Miscellaneous
• Security Cameras
• Sewing Machines
Factory Automation
Robotics
Development Trend
High Reliability Series (36V CLK-IN)
BD6425EFV (1.5A)
High Reliability Series (36V PARALLEL-IN)
BD6423EFV (1.0A)
BD63847EFV (2.0A)
High Voltage Series (45V CLK-IN)
Microstep Series (36V CLK-IN)
BD63860EFV (2.5A)
BD63843EFV (1.0A)
Standard Series (36V PARALLEL-IN)
BD63876EFV (2.0A)
BD63877EFV (2.0A)
Standard Series (36V CLK-IN)
BD63874EFV (1.5A)
BD63875EFV (1.5A)
Low Voltage Series (PARALLEL-IN)
BD63872EFV (1.0A)
BD63873EFV (1.0A)
BD6290EFV (0.8A)
BD63801EFV (0.8A)
BD6380EFV (0.8A)
BD6381EFV (1.2A)
2013
Year
Series Compatibility
Advantages
• Identical pin-out configuration and package throughout entire series
• Easy thermal design/standardization
• Enables driver replacement in final step of design phase
• Short development cycle and reduced risk related to motor change
• Optimal driver available for virtually any motor spec
• Low price
High Voltage Series (CLK-IN)
BD6425EFV (1.5A)
BD6423EFV (1.0A)
BD63877EFV (2.0A)
BD63875EFV (1.5A)
BD63873EFV (1.0A)
BD63876EFV (2.0A)
BD63874EFV (1.5A)
High Reliability Series (CLK-IN)
High Reliability Series (PARALLEL-IN)
Microstep Series (CLK-IN)
← Package & Pin
Compatible
← Package & Pin
BD63872EFV (1.0A)
Compatible
Standard Series
BD63860EFV (2.5A)
BD63847EFV (2.0A)
BD63843EFV (1.0A)
Low Voltage Series
(PARALLEL-IN)
63847 & 63843 are
Package & Pin
Compatible
BD6290EFV (0.8A)
BD63801EFV (0.8A)
BD6381EFV (1.2A)
BD6380EFV (0.8A)
Package Benefits
Conventional
2.2W
ROHM
4.0W
Unit: mm
Performance and Reliability
Technology
• Single power supply
• Ghost Supply Prevention (GSP)
• Mixed Decay Mode
• Linearly variable fast/slow decay ratio
• Pin-compatible lineup
• Bipolar PWM constant current drive
• Thin, compact power package
• Power DMOS
Protection
• Over-Current Protection (OCP)
• Thermal Shutdown (TSD)
• Under-/Over-Voltage Lockout (UVLO/OVLO)
Safety
• IC reverse polarity protection
• High ESD resistance: 4000V (HBM)/400V (MM)
• IC pin short protection
• No charge pump
Single Power Supply Drive
Advantages
• No separate power supply required for logic (reduces external component count - no bypass
capacitor needed)
• Simplifies power up/down sequence
• Simplifies PCB layout and routing
Dual Power Supply
Single Power Supply
VM
Vcc
Logic
VM
Internal
Regulator
Driver
Logic
Note: Does not apply to
low voltage solutions
Driver
Ghost Supply Prevention (GSP)
Advantages
• Prevents malfunctions in motor driver IC and other ICs on the same supply line (Vcc)
• Simplifies power up/down sequence
Malfunctions
No Malfunctions
Vcc = Vinput-１Vf Vcc
Vcc
No Pass Route
input
input
Microcontroller
Microcontroller
GND
GND
Linearly Variable Fast/Slow Decay Ratio
Output current is distorted during
current ramp-down
Slow Decay
Mix Decay
- Better
Mix Decay
Vibration / Noise
VDS adjusts to motor and control
signals
=
Improved characteristics
- Better
Output Current (in Quarter Steps)
Over-Current Protection (OCP)
Advantages
• Provides better, more reliable protection than a fuse
• Latch-type OCP provides instantaneous protection
Image of chip damaged due to
overcurrent
Short-Circuit
Instantaneous
Protection
(200 μsec/DIV)
4 µs
Without OCP
Output Current (5A/DIV)
Output Current (5A/DIV)
With OCP
Short-Circuit
Failure
(200 μsec/DIV)
No Charge Pump
Advantages
• Fewer external components (eliminates 2+ high-voltage electrolytic capacitors)
• High resistance to failure
• Reduced EMI
Charge Pump Circuit
CP1
Vcc
Vcc
CP2
VG
PreDriver
Nch
OUT
Nch
Pch
PreDriver
OUT
Nch
RNF
RNF
BD63843/47EFV (Microstep / 36V)
Features
• Supply voltage: 36V Vcc (internal voltage
regulator)
• DMOS output (Pch + Nch) (1.0A Io max.:
BD63843EFV / 2.0A max.: BD63847EFV)
• Constant current PWM driver
• Serial/CLK IN with built-in translator
• No charge pump required
• Full-/Half-/Eighth-/Sixteenth-step
• Mixed/Auto decay modes
• Linearly variable fast/slow decay ratio
• Integrated 4-bit DAC
• Multiple protection functions:
TSD/UVLO/OVLO/OCP
• HTSSOP-B28 package
4.7 w
Block Diagram
BD638xEFV Series (Low Voltage Type)
Features
• Wide supply voltage range
• Vcc: 2.5 - 5.5V
• VM1,2: 4 - 13.5V
(BD6380EFV), 6 - 13.5V
(BD6381EFV)
• DMOS output
• Io (max): 0.8A (BD6380EFV)
• Io (max): 1.2A (BD6381EFV)
• Constant current PWM driver (Fixed
Off Time Type)
• Reference voltage: 1V ± 3%
• Multiple protection functions:
• TSD/UVLO/OCP
• Crossover current protection
• IC pin short protection
• Standby current: ~ 0µA
• HTSSOP-B24 package
Block Diagram
4.7uF
0.1uF
VCC
24
VREF
VREF
23
Current Limit Comp.
VLIM1
3
9
Predriver
CR1
5
39kΩ
10
11
12
CR
Timer
VM1
OUT1A
OUT1B
RNF1
0.3Ω
4
1000pF
SENSE1
PS 2
IN1A 6
IN1B 7
IN2A 19
UVLO
Logic
47uF
TSD
OCP
IN2B 18
CR2
20
39kΩ
16
CR
Timer
Predriver
1000pF
15
14
13
VLIM2
VM2
OUT2A
OUT2B
RNF2
22
Current Limit Comp.
1
GND
21
SENSE2
0.3Ω
0.1uF
BD642xEFV Series (High Voltage Type)
Features
• Supply voltage: 42V Vcc (Internal
voltage regulator)
• Output current
• Io (max): 1.5 A (BD6425EFV)
• Io (max): 1.0 A (BD6423EFV)
• Constant current PWM driver
• Multiple protection functions
• TSD/UVLO/OCP
• IC pin short protection
• 8kV ESD resistance
• HTSSOP-B28 package
(BD6425EFV)
• HTSSOP-B24 package
(BD6423EFV)
BD6425EFV Block Diagram & Application
Circuit
Comprehensive Support System
Support is available at all stages of product test/evaluation and during
the design process. Feel free to consult with us on any matter.
IC Selection
ROHM’s short form catalog and component-specific selection guides facilitate
quick and easy selection of potential solutions for customer applications.
Testing & Evaluation
Detailed technical notes allow design engineers to assess the capabilities and
benefits of ROHM’s solutions. Evaluation hardware is available upon request.
Integration of ROHM’s Solutions in Customer Applications
ROHM’s tech notes address numerous design topics. E-mail support is
available to assist with issues such as board layout/routing and external
component selection.
Operational Analysis
ROHM engineers can provide performance improvement recommendations by analyzing customer designs.
Troubleshooting
ROHM provides services such as evaluation of customer board layout/routing and testing via EMI scan.
Failure Resolution
ROHM’s Quality Assurance Centers will issue a preliminary report within 24 hours of receipt of suspect
components. Analysis and failure reproduction will then be conducted and relevant
precautions/countermeasures recommended.
Chemical Compliance
ROHM complies with all major substance directives
and regulations
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Restriction of Hazardous Substances (RoHS)
Deca BDE / PFOS
Registration Evaluation Authorization of Chemicals (REACH)
Halogen-free (HF)
Sample RoHS-Compliant Product List
REACH Statement
Online Support: www.ROHM.com
A number of support tools are available
for many P/Ns:
»Detailed materials composition
»Technical notes (for ICs)
»Supplementary information (FAQs)
»Design simulation tool
Summary
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A focus on integration along with package and pin
compatibility has resulted in a product offering which
has eased the burden on designers
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Through the use of packaging with a bottom side heat
sink and the availability of features such as serial CLK
IN clock signal control, ROHM has been able to
reduction the size and complexity of its drivers
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Elimination of the ghost supply path has improved
operational reliability while the addition of overcurrent
protection combined with robust resistance to ESD has
made ROHM stepper motor drivers less prone to failure
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Expansion of the product offering to include microstep
and high voltage solutions has allowed ROHM to
branch out into applications that were previously out of
reach