IRF OM9373SP

PD-94705
OM9373
OM9373SF
OM9373SP
FULL-FEATURED POWER MODULE
FOR DIRECT DRIVE OF
3-PHASE BRUSHLESS DC MOTOR
F-43 / MP3-43L Packages
25A Push-Pull
3-Phase Brushless DC Motor
Controller / Driver Module
in a Power Flatpack
F-43
Description:
The OM9373 is one of a series of versatile, integrated
three-phase brushless DC motor controller/driver
subsystems housed in a 43 pin power flatpack. The
OM9373 is best used as a two quadrant speed
controller for controlling/driving fans, pumps, and
motors in applications which require small size.
Many integral control features provide the user much
flexibility in adapting the OM9373 to specific system
requirements.
The small size of the complete subsystem is ideal for
aerospace, military, and high-end industrial applications.
Two package types provide a broad range of cost
and screening options to fit any application.
MP3-43L
Features:
n Fully Integrated 3-Phase Brushless DC Motor
n
n
n
n
n
n
n
n
Control Subsystem includes Power Stage,
Non-Isolated Driver Stage and Controller Stage
MOSFET Output Stage
25A Average Phase Current with 80V
Maximum Bus Voltage
Internal Precision Current Sense Resistor
(6W Max. Dissipation)
Speed and Direction Control of Motor
Brake Input for Dynamic Braking of Motor
Overvoltage/Coast Input for Shutdown of
All Power Switches
Soft Start for Safe Motor Starting
Unique Hermetic or Plastic Ring Frame Power
Flatpacks
Hermetic (3.10” X 2.10” X 0.385”)
Plastic Ring Frame (4.13” X 2.00” X 0.49”)
Applications:
n Fans and Pumps
n Hoists
n Actuator Systems
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1
11/21/03
OM9373
Absolute Maximum Ratings
Parameter
Motor Supply Voltage
Peak Motor Supply Voltage
Symbol
Value
Vm
80
Vm pk
100
Units
V
Io
25
A*
Peak Phase Output Current
Iom
50
Apeak **
Control Supply Voltage
Vcc
+18
Average Phase Output Current
Logic Input Voltage (Note 1)
Reference Source Current
-30
Error Amplifier Input Voltage Range
( EA1+ / EA1-)
Error Amplifier Output Current
Spare Amplifier Input Voltage
V
-0.3 to +8.0
( EA2+ / EA2-)
mA
-0.3 to +10
V
±8
mA
-0.3 to +10
V
±8
mA
-0.3 to +6.0
V
±10
mA
PWM Input Voltage
-0.3 to +6.0
V
Operating Junction Temperature
-55 to 150
Storage Temperature Range
-65 to 150
Spare Amplifier Output Current
Current Sense Amplifier Input Voltage
(ISH / ISL)
Current Sense Amplifier Output Current
Tachometer Output Current
Lead Soldering Temperature, 10s maximum, 0.125" from case
Package Isolation Voltage
Power Switch Junction-to-Case Thermal Resistance
°C
300
600
0.35
Vrms
°C/W
Symbol
Value
Units
Vm
+48
V
Io
25
A
V cc
15+10%
Vil
Vih
0.8
RθJC
* TCASE = 25°C
* * TCASE = 25°C, Maximum pulse width = 10 mS
Recommended Operating Conditions ( Tcase = 25°C )
Parameter
Motor Power Supply Voltage
Average Phase Output Current
With Internal Current Sense Resistor ( Note2 )
Each Power Switch
Control Supply Voltage
Logic Low Input Voltage (maximum)
Logic High Input Voltage (minimum)
V
2.0
Note 1: Logic Inputs: Direction, Hall Inputs (H1--- H3) Overvoltage - Coast, Speed, and Quad Select.
Note 2: The internal 5mΩ current sense resistor is limited to 6 Wdc power disipation. Other values are avaliable.
Please contact International Rectifier for more information.
2
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OM9373
Electrical Characteristics
Parameter
Symbol
Test Conditions (Note 1)
Min. Typ. Max. Units
Power Output Section
Zero Gate Voltage Drain Current
Drain-to-Source On-Resistance
Gate Body Leakage Current
Idss
Vds = 80Vdc, Vgs = 0V
Rds(on) Id = 35A, Vgs = 10V ( Note 4 )
Igssr Vgs = 20Vdc, Vds = 0V
-
-
-
-
-
-
250
µΑ
0.024 Ohms
100
nA
Diode Forward Voltage
Vf
IS = 35A
-
-
0.9
V
Diode Reverse Recovery Time
trr
IS = 25A, di/dt = -100A/µsec, VGS = 0V
-
-
200
nS
Icc
VCC over operating range
-
-
100
mA
9.45
13
-
-
V
4.9
5.0
5.1
4.7
5.0
5.3
ILOAD = 0mA to -20mA
-40
-5.0
30
-
mA
mV
mA
Control Section
Control Supply Current
Control Turn-On Threshold
Driver Turn-On Threshold
Vcc(+) TC over operating range
Reference Section
Output Voltage
Output Voltage
V ref
TC over operating range
V
Output Current
Load Regulation
Io
Short Circuit Current
Isc
TC over operating range
50
100
150
EA1 / EA2 Input Offset Current
Ios
V(pin 2) = V(pin 4) = 0V,
-30
-3.0
0
EA1 / EA2 Input Bias Current
Iin
V(pin 3) = V(pin 6) = 0V
V(pin 2) = V(pin 4) = 0V,
-50
-45
0
-
-
7.0
mV
0
-
6.0
V
0
3.0
30
µΑ
µΑ
Error / Spare Amplifiers Section
Input Offset Voltage
Amplifier Output Voltage Range
Vos
V(pin 3) = V(pin 6) = 0V
0V < Vcommon-mode < 3.0V
-
nA
PWM Comparator Section
Iin
V(pin 9) = 2.5V
ISH / ISL Input Current
Iin
V(pin 12) = V(pin 13) = 0V,
-850
-320
0
Input Offset Current
Ios
V(pin 12) = V(pin 13) = 0V,
-
±2.0
±12
Peak Current Threshold Voltage
Vpk
V(pin 12) = 0V, V(pin 13) Varied to
0.14
0.20
0.26
Over Current Threshold Voltage
Voc
Threshold
0.26
0.30
0.36
V
ISH / ISL Input Voltage Range
Amplifier Voltage Gain
AV
( Note 2 )
V(pin 12) = 0.3V, V(pin 13) = 0.5V to 0.7V
-1.0
1.75
1.95
2.0
2.15
V/V
V(pin 12) = V(pin 13) = 0.3V
2.4
2.5
2.65
V
PWM Input Current
Current-Sense Amplifier Section
Amplifier Level Shift
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3
OM9373
Electrical Characteristics - Continued
Parameter
Symbol Test Conditions (Note 1) Min.
Typ. Max. Units
Logic Input Section
H1, H2, H3 Low Voltage Threshold
Vil
H1, H2, H3 High Voltage Threshold
Vih
H1, H2, H3 Input Current
Iin
Quad Select / Direction Threshold Voltage
Vth
Quad Select Voltage Hysteresis
Direction Voltage Hysteresis
Quad Select Input Current
Direction Input Current
0.8
1.0
1.2
1.6
1.9
2.0
TC over operating range,
-400
-250
-120
V(pin 20, 21, or 22) = 0Vdc
TC over operating range
0.8
1.4
2.0
V
-
70
-
mV
TC over operating range
Vh
V
µΑ
-
0.6
-
V
-30
50
150
µΑ
-30
-1.0
30
1.65
1.75
1.85
1.55
0.05
1.65
0.10
1.75
0.15
V
Vh
Iin
-10
-1.0
0
µΑ
-10
-5.0
µΑ
lin
Overvoltage / Coast Input Section
Overvoltage / Coast Inhibit Threshold Voltage
Overvoltage / Coast Restart Threshold Voltage
Overvoltage / Coast Hysteresis Voltage
Overvoltage / Coast Restart Input Current
Vth
TC over operating range
Soft-Start Section
Soft-Start Pull-Up Current
Soft-Start Discharge Current
Soft-Start Reset Threshold Voltage
Ip
V(pin 18) = 0V
-16
Id
V(pin 18) = 2.5V
0.1
0.4
3.0
mA
0.1
0.2
0.3
V
4.7
5.0
5.3
-
-
0.2
85
100
140
-
0.1
-
%
-1.9
-
mA
Vth
Tachometer/Brake Section
Tachometer Output High Level
Voh
Tc over operating range
Tachometer Output Low Level
Vol
(pin15) 10KΩ to 2.5V
Tachometer On-Time
ton
V
µS
Tachometer On-Time Variation
-
TC over operating range
Brake/Tach Timing Input Current
Iin
V(pin 16) = 0V
-4.0
Brake/Tach Timing Threshold Voltage
Vth
TC over operating range
0.8
1.0
1.2
Voltage Hysteresis
Vh
-
0.09
-
Speed Input Threshold Voltage
Vth
220
257
290
Speed Input Current
Iin
-30
-5.0
30
mV
µA
13.5
14.8
20
KHz
TC over operating range
V
Oscillator Section
Oscillator Frequency
fo
Measured at pin 10
Specification Notes:
1. All parameters specified for Ta = 25°C, Vcc = 15Vdc, Rosc= 75KΩ (to Vref), Cosc = 1800pF, and all Phase Outputs unloaded (Ta-Tj).
All negative currents shown are sourced by (flow from) the pin under test.
2. Either ISH or ISL may be driven over the range shown.
3. Bold parameters tested over temperature range.
4. Pulse Test: Pulse Width £ 300 µSec,Duty Cycle £ 2%.
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OM9373
APPLICATIONS
Start-Up Conditions
The OM9373 3-phase brushless DC motor controller/
driver is designed to drive fractional to integral
horsepower motors. To ensure proper operation, it is
necessary to ensure that the high-side bootstrap
capcitors are charged during initial start-up. However,
the method(s) used to ensure this may be dependant
upon the application. For example, some applications
may only require that OV_COAST (pin 17) be
connected to ground, either via a hardwire connection
or via a switch (Enable/Disable), before applying Vcc.
When Vcc is applied, the controller/driver is forced
into brake mode for approximately 200µs (all highside drivers are disabled and all low-side drivers are
enabled).
This may not be adequate for other applications;
while maintaining a constant speed command,(above
zero),the RC_BRAKE (pin 16) may have to be
momentarily connected to ground via a switch,
either manually or electronically (ref. Figure 1).
Note that with the component values shown in
Figure 1, RC_BRAKE is pulled for low for approximately
300ms after applying Vcc at pin 1.
Fig 1: Optional Start-Up Circuit
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5
OM9373
Modes of Operation
Figures 2 and 3, shown on the following pages,
provides schematic representations of typical voltagemode and current -mode applications for the OM9373
controller/driver.
Figure 2 represents the implemenation of a typical
voltage-mode controller for velocity control. A voltage
or speed command is applied to the noninverting
input of the error amplifier which is configured as
voltage follower. The ouput of the error amplifier is
compared to a pulse width modulated ramp,and
since motor speed is nearly proportional to the
average phase output voltage, the average speed is
controlled via duty cycle control. If a speed feedback
loop is required, the tachometer output can be
connected to the inverting input of the error amplifier
via a loop compensation network.
Figure 2 also shows the implementation of the
cycle-by-cycle current limit/overcurrent protection
feature of the OM9373. The load current is monitored
red via the controller’s internal sense resistor. The
current sense signal is filtered and fed into the current
rent sense amplifier where the absolute value of
ISH-ISL is multiplied by two and biased up by 2.5V
The output of the current sensor amplifier is compared to
a fixed reference, thus providing cycle-by-cycle
current limiting and/or overcurrent protection as
necessary. The typical peak current threshold (ISL-ISH)
is 0.2V; the typical over current threshold (ISH-ISL) is
0.3V.
Fig 2: Implementation of a Voltage -Mode Controller
+15V
10uF
+
.1uF
3.24k
COMMAND
1k
1.50k
.1uF
10k
.1uF
FROM MOTOR HALL SENSORS
H3
H2
H1
4700pF
232
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Vcc
EA1EA2+
EA1+
VREF
EA2EA2_OUT
EA1_OUT
PWM_IN
OSCILLATOR
I_SENSE
ISH
ISL
QUAD_SEL
TACH_OUT
BRAKE
OV_COAST
SOFT_START
GROUND
H3_HALL_INPUT
H2_HALL_INPUT
H1_HALL_INPUT
SPEED_IN
DIRECTION
CSH
CSL
V_MOTOR
42
PHASE_A_OUT
41
PHASE_A_OUT
SOURCE_A
SOURCE_A
V_MOTOR
V_MOTOR
43
C_BUS
+
C_FILT
40
39
38
37
PHASE_B_OUT
36
PHASE_B_OUT
SOURCE_B
SOURCE_B
V_MOTOR
MOTOR
35
34
33
32
PHASE_C_OUT
31
PHASE_C_OUT
N/C
SOURCE_C
30
29
28
MOTOR_RETURN
27
MOTOR_RETURN
H1
H2
H3
HALL SENSORS
232
6
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OM9373
Figure 3 represents the implementation of a typical
current-mode controller for torque control. The load
current is monitored via the controller’s internal sense
resistor. The current sense signal is filtered and fed
into the current sense amplifier where the absolute
value of ISH-ISL is multiplied by two and biased up by
2.5V. Besides the implementation of the cycle-bycycle current limit/overcurrent protection feature of the
OM9373 discussed in the preceding paragraph, the
output of the current sense amplifier is fed into the
error amplifier which is configured as a differential
amplifier. An error signal representing the difference
between the current command input and the value
of the amplified current sense signal is produced.
Then it is compared to a pulse width modulated
ramp and since torque is nearly proportional to the
average phase output current, the torque controlled
via duty cycle control.
Fig 3: Implementation of a Current-Mode Controller
CURRENT_COMMAND
+15V
10uF
+
.1uF
3.24k
35.6k
1k
1
2
3
4
5
6
7
8
9
OFFSET
1800pF
3.24k
.26uF
2k
43k
.1uF
10k
.1uF
FROM MOTOR HALL SENSORS
H3
H2
H1
4700pF
232
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Vcc
EA1EA2+
EA1+
VREF
EA2EA2_OUT
EA1_OUT
PWM_IN
OSCILLATOR
I_SENSE
ISH
ISL
QUAD_SEL
TACH_OUT
BRAKE
OV_COAST
SOFT_START
GROUND
H3_HALL_INPUT
H2_HALL_INPUT
H1_HALL_INPUT
SPEED_IN
DIRECTION
CSH
CSL
V_MOTOR
PHASE_A_OUT
PHASE_A_OUT
SOURCE_A
SOURCE_A
V_MOTOR
PHASE_B_OUT
PHASE_B_OUT
SOURCE_B
SOURCE_B
V_MOTOR
PHASE_C_OUT
PHASE_C_OUT
N/C
SOURCE_C
43
V_MOTOR
42
41
C_BUS
+
C_FILT
40
39
38
37
36
MOTOR
35
34
33
32
31
30
29
28
MOTOR_RETURN
27
MOTOR_RETURN
H1
H2
H3
HALL SENSORS
232
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7
OM9373
Simplified Block Diagram
8
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OM9373
Pin Descriptions / Functionality
VCC (Pin 1) -- The Vcc Supply input provides bias
voltage to all of the internal control electronics
within the OM9373, and should be connected to a
nominal +15Vdc power source. High frequency
bypass capacitors (10uF polarized in parallel with
0.1uF ceramic are recommended) should be connected
as close as possible to pin 1 and Ground (pin 19).
ERROR AMPLIFIER (EA1- Input, Pin 2; EA1+
Input, Pin 4; EA1 Output, Pin 8) -- The Error
Amplifier is an uncommitted LM158-type operational
amplifier, providing the user with many external
control loop compensation options. This amplifier is
compensated for unity gain stability, so it can be
used as a unity gain input buffer to the internal
PWM comparator when pin 2 is connected to pin 8.
The output of the Error Amplifier is internally connected
to the PWM comparator's "-" input, simplifing external
layout connections.
+5V REFERENCE OUTPUT (Pin 5) -- This output
provides a temperature-compensated, regulated
voltage reference for critical external loads. It is
recommended that this pin be used to power the
external Hall-effect motor position sensors. By design,
the +5V reference must be in regulation before the
remainder of the control circuitry is activated. This
feature allows the Hall-effect sensors to become
powered and enabled before any Phase Output is
enabled in the OM9373 preventing damage at turnon. High-frequency bypass capacitors (10uF polarized
in parallel with 0.1uF ceramic are recommended)
should be connected as close as possible to pin 5
and Ground (pin 19).
SPARE AMPLIFIER (EA2- Input, Pin 6; EA2+
Input, Pin 3; EA2 Output, Pin 7) -- The Spare
Amplifier is an uncommitted LM158-type operational
amplifier, and in addition to the internal error
amplifier, provides the user with additional external
control loop compensation options. This amplifier is
also compensated for unity gain stability and it can
be used as a unity gain input buffer when pin 6 is
connected to pin 7. If the Spare Amplifier is unused,
pin 3 should be connected to Ground, and pin 6
should be connected to pin 7.
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PWM INPUT (Pin 9) -- This pin is connected to the
"+" input of the internal PWM comparator. The PWM
output clears the internal PWM latch, which in turn
commands the Phase Outputs to chop. For voltagemode control systems, pin 9 may be connected to
the Oscillator Timing Input, pin 10.
OSCILLATOR TIMING INPUT (Pin 10) -- The Oscillator
Timing Input sets a fixed PWM chopping frequency
by means of an internal resistor (Rosc), whose
value is set to 75kΩ, connected from pin 10 to the +5V
Reference Output, and an internal capacitor (Cosc),
whose value is 1800pF, connected from pin 10 to
Ground. In custom applications, the recommended
range of values for Rosc is 10kΩ to 100kΩ, and for
Cosc is 0.001uF to 0.01uF and the maximum operating
frequency should be kept below 20kHz. The approximate
oscillator frequency is:
fo =
2
[ Hz ]
( Rosc x Cosc )
The voltage waveform on pin 10 is a ramp whose
magnitude is approximately 1.2Vp-p, centered at
approximately 1.6Vdc. In addition to the voltagemode PWM control, pin 10 may be used for slope
compensation in current-mode control applications.
ISENSE (Pin 11) -- This pin is connected to the
output of the internal current-sense amplifier. It
drives a peak-current (cycle-by-cycle) comparator
which controls Phase Output chopping, and a failsafe current comparator which, in the event of an
output overcurrent condition, activates the soft-start
feature and disables the Phase Outputs until the
overcurrent condition is removed. The magnitude of
the voltage appearing at pin 11 is dependent upon
the voltages present at the current-sense amplifier
inputs, ISH and ISL:
V(Isense) = 2.5V + [2 x ABS (ISH - ISL)] [ V ]
CURRENT SENSE INPUTS (ISH, Pin 12; ISL, pin 13)
These inputs to the current-sense amplifier are inter
changeable and they can be used as differential
inputs. The differential voltage applied between pins
12 and 13 should be kept below +/-0.5Vdc to avoid
saturaion.
9
OM9373
QUAD SELECT INPUT (Pin 14) -- This input is used
to set the OM9373 in a half control or full control
chopping regime. When driven with a logic low level,
the OM9373 is in the half control mode, whereby only
the three lower (pull-down) power switches associated
with the Phase Outputs are allowed to chop. Alternately,
when driven with a logic high level, the OM9373 is
in the full control mode, where all six power switches
(pull-up and pull-down) associated with the Phase
Outputs are chopped by the PWM. During motor braking,
changing the logic state of the Quad Select Input
has no effect on the operation of the OM9373.
TACHOMETER OUTPUT (Pin 15) -- This output
provides a fixed width 5V pulse when any Halleffect Input (1, 2 or 3) changes state. The pulse width
of the Tachometer Output is set internally in the
OM9373 to 113µs (nominal). The average value of
the output voltage on pin 15 is directly proportional
to the motor's speed, so this output may be used
(with an external averaging filter) as a true tachometer
output, and fed back to the Speed Input (pin 23) to
sense the actual motor speed.
Note: Whenever pin 15 is high, the internal Hall-effect
position latches are inhibited (i.e. "latched"), to reject
noise during the chopping portion of the commutation
cycle, and this makes additional com mutations
impossible. This means that in order to prevent false
commutation at a speed less than the desired maximum
speed, the highest speed as observed at the Tachometer
Output should be set above the expected maximum
value.
BRAKE / TACH TIMING INPUT (Pin 16) -- The
Brake/Tach Timing Input is a dual-purpose input.
Internal to the OM9373 are timing components tied
from pin 16 to Ground (a 51kΩ resistor and a 3300pF
capacitor) These components set the minimum pulse
width of the Tachometer Output to 113µs, and this
time may be adjusted using external components,
according to the equation:
T(tach) = 0.67 x (Ct + 3300pf) x Rt x 51kΩ
Ω (µs)
Ω
Rt + 51kΩ
(
)
The recommended range of external resistance (to
Ground) is 15kΩ to ∞, and the range of external
capacitance (to Ground) is 0pF to 0.01uF. With each
Tachometer Output pulse, the capacitor tied to pin
16 is discharged from approximately 3.33V to
10
approximately 1.67V by an internal timing resistor.
The Brake / Tach Timing Input has another function.
If this pin is pulled below the brake threshold
voltage, the OM9373 will enter the brake mode. The
brake mode is defined as the disabling of all three
high-side (pull-up) drivers associated with the Phase
Outputs, and the enabling of all three low-side (pulldown) drivers.
OVERVOLTAGE / COAST INPUT (Pin 17) -- This
input may be used as a shutdown or an enable/
disable input to the OM9373. Also, since the switching
inhibit threshold is so tightly defined, this input can
be directly interfaced with a resistive divider which
senses the voltage of the motor supply, Vm, for
overvoltage conditions. A high level (greater than the
inhibit threshold) on pin 17 causes the coast condition
to occur, whereby all Phase Outputs revert to a Hi-Z
state and any motor current which flowed prior to the
Overvoltage/ Coast command and is commutated via the
power "catch" rectifiers associated with each Phase
Output.
SOFT-START INPUT (Pin 18) -- The Soft-Start input
is internally connected to a 10µA (nominal) current
source, the collector of an NPN clamp/discharge
transistor, and a voltage comparator whose softstart/restart threshold is 0.2Vdc (nominal). An
external capacitor is connected from this pin to
Ground (pin 19). Whenever the Vcc supply input
drops below the turn-on threshold, approximately
9Vdc, or the sensed current exceeds the overcurrent threshold, approximately 0.3V at the current
sense amplifier, the soft-start latch is set. This drives
the NPN clamp transistor which discharges the
external soft-start capacitor. When the capacitor
voltage drops below the soft-start/restart threshold
and a fault condition does not exist, the soft-start
latch is cleared; the soft-start capacitor charges via
the internal current source.
In addition to discharging the soft-start capacitor, the
clamp transistor also clamps the output of the error
amplifier internal to the controller IC, not allowing
the voltage at the output of the error amplifier to
exceed the voltage at pin 18, regardless of the
inputs to the amplifier. This action provides for an
orderly motor start-up either at start-up or when
recovering from a fault condition.
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OM9373
GROUND (Pin 19) - The voltages that control the
OM9373 are referenced with respect to this pin. All
bypass capacitors, timing resistors and capacitors,
loop compensation components, and the Hall-effect
filter capacitors must be referenced as close as
possible to pin 19 for proper circuit operation.
Additionally, pin 19 must be connected as close as
physically possible to the Motor Return, pins 27 and
28.
HALL-EFFECT INPUTS (H1, Pin 22; H2, Pin 21; H3,
Pin 20) - Each input has an internal pull-up resistor
to the +5V Reference. Each input also has an
internal 180pF noise filter capacitor to Ground. In
order to minimize the noise which may be coupled
from the motor commutation action to these inputs, it
is strongly recommended that additional external
filter capacitors, whose value is in the range of
2200pF, be connected from each Hall-Effect Input
pin to Ground. Whatever capacitor value is used, the
rise/fall times of each input must be guaranteed to
be less than 20us for proper tachometer action to
occur. Motors with 60 degree position sensing may
be used if one or two of the Hall-effect sensor
signals is inverted prior to connection to the HallEffect Inputs.
SPEED INPUT (Pin 23) - This pin is connected to the
“+” input of a voltage comparator, whose threshold
is 0.25Vdc. As long as the Speed Input is less than
0.25V, the direction latch is transparent. When the
Speed Input is greater than 0.25V, then the direction
latch inhibits all changes in direction. It is recommeded,
especially while operating in the half control mode,
that the Tachometer Output is connected to the
Speed Input via a low-pass filter, such that the
direction latch is transparent only when the motor is
spinning very slowly. In this case, the motor has too
little stored energy to damage the power devices
during direction reversal.
DIRECTION INPUT (Pin 24) - This input is used to
select the motor direction. This input has an internal
protection feature: the logic-level present on the
Direction Input is first loaded into a direction latch,
then shifted through a two-bit shift register before
interfacing with the internal output phase driver
logic decoder. Also, protection circuitry detects
when the input and the output of the direction latch
or the 2-bit shift register are different, and inhibits
the Phase Outputs (i.e. Hi-Z) during those times. This
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feature may be used to allow the motor to coast to a
safe speed before a direction reversal takes place.
Power stage cross-conduction ( current "shoot-through”
from Vmotor to Ground through simultaneously enabled
pull-up and pull-down drivers ) is prevented by the shift
register as it is clocked by the PWM oscillator, so that a
fixed delay of between one and two PWM oscillator clock
cycles occurs. This delay or "dead-time" guarantees that
power-stage cross-conduction will not occur.
CURRENT SENSE OUTPUTS (CSH, Pin 25; CSL,
Pin 26) - The Current Sense Outputs produce a
differential voltage equal to the motor current times
the sense resistance value (5mΩ nominal). There is
an internal 0.018µF filter capacitor across pins 25
and 26, and two 100Ω series resistors, one between
each pin and each end of the current sense resistor.
To configure the current sense amplifier for cycleby-cycle current limiting and/or overcurrent protection,
connect pin 25 to pin 12 (ISH) and pin 26 to pin 13
(ISL).
MOTOR RETURN (Pins 27 and 28) - These pins are
connected to the most negative terminal of the
motor supply (Vm-). This connection is electrically
isolated from the logic ground internal to the OM9373
package to minimize, if not eliminate, noise on the
logic ground. The connection to the logic ground is
made by the user external to the package (refer to
Ground (pin 19)). In order to minimize packaing
losses and parasitic effects, it is essential that both
of these pins be firmly connected to the motor supply
Ground, with as short a connection as physically
possible.
SOURCE (Pins 29, 34, 35, 39 and 40) - The source
pins form the low-side connection of the pull-down
switches associated with each Phase Output. Because
of the switching current capability of the OM9373, all
5 pins should be externally connected together with
a low impedance bus to minimize losses and voltage
differentials. Also, due to layout design considerations,
pin 29 is internally connected to the "top" of the internal
current-sense resistor.
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OM9373
PHASE OUTPUTS (Phase A, Pins 41 and 42;
Phase B, Pins 36 and 37; Phase C, Pins 31 and 32)
These outputs are connected to either Vmotor via
the pull-up driver or Source via the pull-down driver,
depending upon the Hall-Effect and Direction Inputs
(see Commutation Truth Table). The two pins associated
with each Phase Output must be connected to one of the
three phases of the motor driven by the OM9373.
VMOTOR (Pins 33, 38, and 43) - These pins are
connected to the most positive terminal of the motor
supply (Vm+). For proper operation, all three pins
must be connected together externally with a low
impedance power bus. The Vmotor power bus
should be bypassed with an adequately voltagerated ceramic capacitor, 0.1µF (typical), and a lowESR electrolytic capacitor, whose capacitance can
be selected by the following: 10µF-per-Ampere of
average motor current from Vmotor to Motor Return.
Note: All connections, including the power bus
capacitor connections, must be made as close as
possible to the Vmotor and Motor Return pins to
minimize parasitic effects.
Pin Designation
Pin No.
Designation
Pin No.
Designation
Pin No.
Designation
1
VCC
12
ISH
23
Speed Input
Pin No. Designation
34
2
EA1 "-" Input
13
ISL
24
Direction Input
35
Source B
3
EA2 "+" Input
14
Quad Select Input
25
CSH
36
Phase B Output
4
5
EA1 "+" Input
15
16
Tachometer Output
+5V Reference Output
Brake/Tach Timing Input
26
27
CSL
Motor Return
37
38
Phase B Output
Vmotor
Source A
Source B
6
EA2 "-" Input
17
Overvoltage/Coast Input
28
Motor Return
39
7
EA2 Output
18
Soft-Start Input
29
Source C
40
Source A
8
EA1 Output
19
Ground
30
( No Connection)
41
Phase A Output
9
10
11
PWM Input
Oscillator Timing Input
20
21
22
H3 Input
H2 Input
H1 Input
31
32
33
Phase C Output
Phase C Output
Vmotor
42
43
Case
Phase A Output
Vmotor
(No Connection)
12
Isense
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OM9373
Commutation Truth Table
Table 1 shows the Phase Output state versus the state
of the Hall-Effect and Direction Inputs. Please note
that the OM9373 Hall-Effect Inputs are Grey-encoded;
that is, only one input is allowed to change from one
input state to another at a time.
The commutation coding shown reflects Hall-Effect
sensors that are spaced at 120° mechanical
increments. Also, internal protection logic disables
all three Phase Outputs when the Hall-Effect Inputs
are set to an illegal condition (i.e. all logic low or all
logic high).
Table 1 - Commutation Truth Table
Digital Inputs
Phase Outputs
Dir
H1
H2
H3
A
B
C
1
0
0
1
Hi-Z
Sink
Source
1
0
1
1
Sink
Hi-Z
Source
1
0
1
0
Sink
Source
Hi-Z
1
1
1
0
Hi-Z
Source
Sink
1
1
0
0
Source
Hi-Z
Sink
1
1
0
1
Source
Sink
Hi-Z
0
1
0
1
Sink
Source
Hi-Z
0
1
0
0
Sink
Hi-Z
Source
0
1
1
0
Hi-Z
Sink
Source
0
0
1
0
Source
Sink
Hi-Z
0
0
1
1
Source
Hi-Z
Sink
0
0
0
1
Hi-Z
Source
Sink
X
X
0
1
0
1
0
1
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Hi-Z
Package and Screening Options
The OM9373 is offered in F-43, a hermetic flatpack
package as well as in MP3-43L, a plastic ring frame,
low profile flatpack package.
MIL-STD-883 screening. The plastic ring frame version is offered in an industrial temperature range of
-40°C to +85°C with limited screening.
The hermetic version is offered in two standard
screening levels: a full military temperature range of
-55°C to +125°C with limited screening and with
The screening levels for the SFB, SFP and SPP
versions are listed in the table below. All tests and
inspections are in accordance with those listed in
MIL-STD-883.
Test / Inspection
SFB
SFP
SPP
Precap Visual Inspection
100%
100%
100%
Temperature Cycle
100%
NA
NA
Mechanical Shock
100%
NA
NA
Hermeticity ( Fine and Gross Leak )
100%
100%
NA
Pre Burn-In Electrical
100%
NA
NA
Burn-In ( 160 hours )
100%
NA
NA
Final Electrical Test
-55°C, 25°C, +125°C
+25°C
+25°C
100%
100%
NA
100%
NA
100%
Group A Testing
Final Visual Inspection
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13
OM9373
Mechanical Outline - F-43 ( OM9373SF )
a Pin 1
Pin 43
Pin 26
Mechanical Outline - MP3-43L ( OM9373SP )
a Pin 1
Pin 43
Pin 26
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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