IRF OMC506

PD-95805
Closed Loop Speed Controller For
3-Phase Brushless DC Motor
MP-3T Package
OMC506
Description:
The OMC506 is an integrated, high density, three phase
Brushless DC (BLDC) motor, speed controller housed in a
MP-3Tpackage. The OMC506 contains the power, driver
and control electronics to adjust timing functions and speed
control loop parameters to optimize the controller for each
application. The electronics contained in the OMC506 are
assembled using mixed process technologies: surface
mount components on a printed circuit board and chip &
wire on an Insulated Metal Substrate.This combination
offers small size, excellent thermal characteristics and
electrically isolated heat sink.
MP-3T
Features:
n 10A Average Phase Output Current
n Over Temperature Protection
n Compensation Circuitry Adjustable to
Motor Parameters
n Speed Controlled by 0 to 5V Linear
Input Signal
n Forward or Reverse Direction
n Isolated, Low Profile Package
Absolute Maximum Ratings
Symbol
VM
Parameter
Units
Motor Supply Voltage
32
Vdc
Peak Motor Supply Voltage
48
V
IO
Average Phase Output Current
10
IOP
Pulsed Output Current ( <1% Duty Cycle )
30
VM pk
IOSC
Oscillator Input Current ( Source or Sink )
30
VREF
Reference Output Voltage ( IREF = 1.0mA )
6.5
IREF
Digital Inputs ( Fwd / Enable / Brake / SA /SB / SC )
Reference Output Current ( VREF = 6.2V )
6.5
10
VSPEED
Speed Control Input Voltage
-0.3 to VREF
VTACH
Tachometer Input Voltage
-0.3 to VREF
VCNTL
Temperature Control Input Voltage
Regulator Output Current ( VREG + 15V )
VCS
Current Sense Input Voltage
TOP
Operating Temperature Range
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A
mA
V
mA
V
6.2
100
mA
-0.3 to 5.0
V
-25 to 85
°C
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11/24/03
OMC506
Electrical Characteristics @ TJ = 25°C (Unless Otherwise Specified)
Characteristics
Parameter
Symbol Min. Typ. Max. Units
Test Conditions
REFERENCE
Reference Output Voltage
Reference Load Current
VREF
IREF
5.9
-
6.24
5.0
6.5
8.0
V
mA
IREF = 1.0mA
OSCILLATOR
FOSC
22
25
28
KHz
VOSCpk
VOSCva
1.2
4.1
1.5
4.5
-
V
V
Vih
V il
3.0
2.2
-
V
Low Input Treshhold Voltage
-
1.7
0.8
V
Treshhold Voltage
Vth
85
101
115
mV
Input Common Mode Volt Range
Vicr
Vib
-
3.0
-
V
Input Bias Current
-
-0.9
-5.0
mA
Output Voltage
Load Regulation
V reg
Ireg
14
-
14.5
0.1
15
0.3
V
%
Output Trip Voltage
VOUT
13
Output Normal Voltage
VON
-
0.13
0.4
V
Trip Temperature
Ttrip
137
145
150
°C
Reset Temperature
Treset
129
137
142
°C
Internal Current Sense Resistor
Rs
Rthjc
9.5
10
-
-
Oscillator Frequency
Sawtooth Peak Voltage
Sawtooth Valley Voltage
ROSC= 4.7K,COSC= 0.01mF
DIGITAL INPUTS
High Input Treshhold Voltage
CURRENT SENSE
VOLTAGE
REGULATOR
10mA < IO < 100mA
THERMAL
Junction-to-Case MOSFET Resist.
13.31 14.79
V
T > T trip, RL = 100K
10.5 mOhm
1.6
°C/W
MP3 Package Application
A new mixed signal module fully integrates power, control functions, and drive circuitry into a single 2” x 4”
x 0.48” package. The module provides closed loop speed control of three phase, brushless DC (BLDC)
motors used in a variety of system applications. The OMC506 has been designed with flexibility in mind.
Timing functions and loop parameters can be adjusted to optimize the OMC506 to each customer’s application.
In addition, the OMC506 has been designed into a MP-3T package. This package uses an insulated metal
substrate, thereby, isolating the module’s electronics from chassis while providing the necesssary thermal
interface for proper performance. The OMC506 offers a high efficiency, flexible, compact, motion control
system in an industry standard footprint.
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OMC506
Block Diagram
RT/CT
VMOTOR
VOUT
CONTROL
OVER
TEMP
CKTRY
FOUT
6.2 V REF
COMPENSATION
TACH IN
VSPEED
SA
SB
SC
TACHOMETER
LOOP
SHAPING
+15 V
+15 V
DRIVER
A
DRIVER
B
DRIVER
C
REGULATOR
FWD/REV
OSC
C.S.+
C.S.BRAKE
ENABLE
A OUT
B OUT
MOT
C OUT
RSENSE
RSENSE
RSENSE RTN
THREE
PHASE
REFRESH
Controller
The OMC506 is based on the Motorola MC33035 Brushless Motor Control I.C. This controller is used in
concert with the motorola MC33039 Closed Loop Brushless Motor Adapter I.C. to provide direct duty cycle
control of the motor speed. The OMC506 provides two quadrant speed control via an analog 0 to 5V signal
applied to the Vspeed ( pin22 ) input. The OMC506 is selected for 60/120 degree hall sensor spacing. The
commutation truth table for the OMC506 is shown in Table 1.
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OMC506
Table 1 - Commutation Truth Table
Inputs
Outputs
SA
120°
SB
SC
F/R
Enable
Brake
AOUT
BOUT
COUT
Fault
1
0
0
1
1
0
1
-
0
1
1
1
0
1
1
0
-
1
0
1
0
1
0
1
1
0
0
1
-
1
0
1
1
1
1
0
0
-
1
1
0
0
1
1
1
0
0
-
0
1
1
0
1
1
1
0
1
0
-
1
1
0
0
0
1
0
0
-
1
1
1
1
0
0
1
0
-
0
1
1
0
1
0
0
1
0
1
0
-
1
0
1
1
0
1
0
1
-
0
1
0
0
1
0
1
0
-
1
0
1
1
0
1
0
1
0
0
1
-
1
1
1
1
X
X
0
-
-
-
0
0
0
0
X
X
0
-
-
-
0
1
1
1
X
X
1
0
0
0
0
0
0
X
X
1
1
0
0
0
0
V
V
V
X
1
1
0
0
0
1
V
V
V
V
V
V
X
X
0
0
1
0
0
-
0
-
0
-
0
0
Notes
1
1
2
Notes:
1) Invalid Sensor Inputs; X= Don’t Care
2) V= Valid Sensor Input
Closed Loop Circuit
Additional amplifiers are used in the OMC506 to provide the necessary control loop compensation for extended
bandwidth. By extending the bandwidth of the direct duty cycle control system, torque pertubations can be
accounted for while regulating the speed of the motor. This allows the module to be used in relatively dynamic
systems as well as constant torque applications. Internally, the compensation circuitry used for control loop
shaping can be tuned to optimize the OMC506 for various applications.
The OMC506 provides directional, braking, and enable interfaces from the controller I.C. (pins 32, 24 and 25,
respectively). The module also allows the user to externally set the pulse width modulation (PWW) frequency
(pin21) as well as the pulse width from the Closed Loop Brushless Motor Adapter (pin 34). This allows a
common module to be used in many applications.
Motor commutation and speed control are derived from the Hall effect sensor signals provided from the motor.
The signals are provided as inputs to the OMC506 (pins 29, 30 and 31). The amplitude of the sensor signals
must be limited, by the user, to +6.2V to insure proper operation of the module.
Finally, the output from the Closed Loop Brushless Motor Adapter is provided as an output of the OMC506.
This signal has fixed amplitude and pre-set pulse width. The frequency is six times that of the motor. This
signal is integrated to produce a voltage proportional to motor speed.
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OMC506
Current Limit
The OMC506 provides outputs from the internal current sense resistor (pin 7& 8). These outputs can be
directly wired to the C.S. +, C.S.- (pin 28 & 27) inputs. The outputs can also be used in external current limit
circuitry. Figure 1 shows a typical connection of the OMC506’s current limit circuitry.
Figure 1 - Current Limit Circuitry
Over Temperature Protection
The OMC506 has been designed with an internal over temperature protection circuit. The circuit provides a
diagnostic in the event an over temperature condition occurs in the power stage. The circuit normally outputs
a voltage level < 0.5Vdc. When the power stage reaches 140°C, the VOUT (pin19) will rise to +15Vdc. The
OMC506 also outputs a control function for this circuitry. A logic “0” at pin 18 will disable the over temperature
circuit and a logic “1” will force VOUT to go high. The over temperature circuitry has been designed to interface
with a system controller. The system controller can act on the pretense of an over temperature and shut the
OMC506 down. The system controller may opt to over ride the over temperature flag and disable the circuit
over temperature circuitry. In addition, the system controller can force the VOUT high as part of a built in test
(BIT) feature at the system level. The over temperature circuitry will reset when the power stage has cooled to
130°C. Finally, an internal diode can be jumpered causing the temperature circuitry to latch on trip, requiring
a power off reset.
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OMC506
Typical Motor Connections
Figure 2 shows a typical application of the OMC506. The user must externally connect an electrolytic capacitor
(value is dependant on the application) bypassed with a ceramic decoupling capacitor. These capacitors
should be as close to the module as feasible. In addition, it is recommended that a transient suppressor also
be added in parallel with the external capacitors to prevent high voltage transients on the motor bus.
Figure 2 - Typical Motor Connections
5V
634
0.1µF
MOT
80.6K
0.01µF
DIAGNOSTIC
+
6.65K
0.01µF
100K
DISABLE
480µF
145 C TRIP
FORCE TRIP
Conclusion
International Rectifier’s OMC506 offers a complete motor control system, that is flexible in design, in a high
density, high power industrial module. The assembly technology makes the OMC506 an ideal candidate in
systems where package size is critical. This power module integrates all the functions necessary to control a
DC brushless motor. The design of the OMC506 is flexible enough to be customized for various applications
while still maintaining a turn-key solution to the end user. Finally, the MP310, as other industrial packages
from International Rectifier, makes the user’s mechanical interface simple while optimizing the thermal transfer
from the module to the heatsink.
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OMC506
Mechanical Outline - MP-3T
2.000
.600
1.350
.325
.150
(4) PLCS.
.250
.135
.500
.050
(34) PLCS.
.150
2.450
3.000
4.000
.300
.500
.250
.020
.480 MAX.
.180
Pin Designation
Pin No.
Designation
Pin No.
Designation
Pin No.
Designation
Pin No.
Designation
1
Power GND
11
Phase A
21
OSC
31
SA
2
3
Power GND
NC
12
13
Phase A
NC
22
23
Vspeed
Tach Input
32
33
Fwd / Rev
FOUT (Tach)
4
Phase C
14
Phase B
24
Brake
34
RT / CT
5
Phase C
15
Phase B
25
Enable
6
7
NC
Rsense return
16
17
Vm
Vm
26
27
Fault
CS -
8
Rsense
18
Control
28
CS+
9
+ 15V
19
29
SC
10
Signal GND
20
VOUT
6.2 VREF
30
SB
Note: Contact IR Leominster for lead bending options
IR WORLD HEADQUARTERS: 233 Kansas St., El Segundo, California 90245, USA Tel: (310) 252-7105
IR LEOMINSTER: 205 Crawford St., Leominster, Massachusetts 01453, USA Tel: (978) 534-5776
Visit us at www.irf.com for sales contact information.
Data and specifications subject to change without notice. 11/03
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