MOTOROLA MC3PHACVFA

Freescale Semiconductor, Inc.
Data Sheet
MC3PHAC/D
Rev. 1, 4/2002
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3-Phase AC Motor
Controller
Overview
The MC3PHAC is a high-performance monolithic intelligent motor controller
designed specifically to meet the requirements for low-cost, variable-speed,
3-phase ac motor control systems. The device is adaptable and configurable,
based on its environment. It contains all of the active functions required to
implement the control portion of an open loop, 3-phase ac motor drive.
One of the unique aspects of this device is that although it is adaptable and
configurable based on its environment, it does not require any software
development. This makes the MC3PHAC a perfect fit for customer applications
requiring ac motor control but with limited or no software resources available.
The device features are:
•
Volts-per-Hertz speed control
•
Digital signal processing (DSP) filtering to enhance speed stability
•
32-bit calculations for high-precision operation
•
Internet enabled
•
No user software development required for operation
•
6-output pulse-width modulator (PWM)
•
3-phase waveform generation
•
4-channel analog-to-digital converter (ADC)
•
User configurable for standalone or hosted operation
•
Dynamic bus ripple cancellation
•
Selectable PWM polarity and frequency
•
Selectable 50/60 Hz base frequency
•
Phase-lock loop (PLL) based system oscillator
•
Serial communications interface (SCI)
•
Low-power supply voltage detection circuit
© Motorola, Inc., 2002
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MC3PHAC/D
Included in the MC3PHAC are protective features consisting of dc bus voltage
monitoring and a system fault input that will immediately disable the PWM
module upon detection of a system fault.
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Some target applications for the MC3PHAC include:
•
Low horsepower HVAC motors
•
Home appliances
•
Commercial laundry and dishwashers
•
Process control
•
Pumps and fans
As shown in Table 1, the MC3PHAC is offered in these packages:
•
Plastic 28-pin dual in-line package (DIP)
•
Plastic 28-pin small outline integrated circuit (SOIC)
•
Plastic 32-pin quad flat pack (QFP)
See Figure 1 and Figure 2 for the pin connections.
Table 1. Ordering Information
Device
2
Operating
Temperature Range
Package
MC3PHACVP
–40°C to +105°C
Plastic 28-pin DIP
MC3PHACVDW
–40°C to +105°C
Plastic 28-pin SOIC
MC3PHACVFA
–40°C to +105°C
Plastic 32-pin QFP
3-Phase AC Motor Controller
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MC3PHAC/D
Overview
VREF
1
28
DC_BUS
RESET
2
27
ACCEL
VDDA
3
26
SPEED
VSSA
4
25
MUX_IN
OSC2
5
24
START
OSC1
6
23
FWD
PLLCAP
7
22
VSS
PWMPOL_BASEFREQ
8
21
VDD
PWM_U_TOP
9
20
VBOOST_MODE
PWM_U_BOT
10
19
DT_FAULTOUT
PWM_V_TOP
11
18
RBRAKE
PWM_V_BOT
12
17
RETRY_TxD
PWM_W_TOP
13
16
PWMFREQ_RxD
PWM_W_BOT
14
15
FAULTIN
VDDA
RESET
VREF
VSS
VSS
VSS
DC_BUS
ACCEL
32
31
30
29
28
27
26
25
Figure 1. Pin Connections for PDIP and SOIC
VDD
PWM_U_BOT
7
18
VBOOST_MODE
PWM_V_TOP
8
17
DT_FAULTOUT
16
PWM_U_TOP
19
RBRAKE
VSS
6
15
PWMPOL_BASEFREQ
20
RETRY_TxD
FWD
5
14
21
PWMFREQ_RxD
4
13
PLLCAP
VSS
START
12
22
FAULTIN
3
11
OSC1
PWM_W_BOT
MUX_IN
10
23
PWM_W_TOP
2
OSC2
9
SPEED
1
PWM_V_BOT
24
VSSA
Figure 2. Pin Connections for QFP
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3-Phase AC Motor Controller
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MC3PHAC/D
AC IN
3-PHASE
AC MOTOR
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BUS VOLTAGE
FEEDBACK
RESISTIVE
BRAKE
CONTROL
TO GATE DRIVES
START/STOP
FORWARD/REVERSE
SPEED
ACCELERATION
PWM’s
MC3PHAC
PWM FREQUENCY
FAULT
SERIAL INTERFACE
PASSIVE
INITIALIZATION
NETWORK
(OPTIONAL)
Figure 3. MC3PHAC-Based Motor Control System
4
3-Phase AC Motor Controller
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MC3PHAC/D
Electrical Characteristics
Electrical Characteristics
Maximum Ratings
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Characteristic(1)
Symbol
Value
Unit
Supply voltage
VDD
–0.3 to +6.0
V
Input voltage
VIn
–0.3 to VDD +0.3
V
Input high voltage
VHi
VDD + 0.3
V
I
± 25
mA
Tstg
–55 to +150
°C
Maximum current out of VSS
IMVSS
100
mA
Maximum current into VDD
IMVDD
100
mA
Maximum current per pin excluding
VDD and VSS
Storage temperature
1. Voltages referenced to VSS
This device contains circuitry to protect the inputs against damage due to high
static voltages or electric fields; however, it is advised that normal precautions
be taken to avoid application of any voltage higher than maximum-rated
voltages to this high-impedance circuit. For proper operation, it is
recommended that VIn and VOut be constrained to the range VSS ≤ (VIn or VOut)
≤ VDD. Reliability of operation is enhanced if unused inputs are connected to
an appropriate logic voltage level (for example, either VSS or VDD).
Functional Operating Range
Characteristic
Operating temperature range
(see Table 1)
Operating voltage range
Symbol
Value
Unit
TA
–40°C to +105°C
°C
VDD
5.0 ± 10%
V
Symbol
Value
Unit
Fosc
4.00 ± 1%
MHz
Control Timing
Characteristic
Oscillator frequency(1)
1. Follow the crystal/resonator manufacturer’s recommendations, as the crystal/resonator
parameters determine the external component values required for maximum stability and
reliable starting. The load capacitance values used in the oscillator circuit design should
include all stray capacitances.
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3-Phase AC Motor Controller
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MC3PHAC/D
DC Electrical Characteristics
Characteristic(1)
Symbol
Min
Max
Unit
VOH
VDD –0.8
—
V
VOHRB
VDD –1.0
—
V
Output low voltage (ILoad = 1.6 mA)
All I/O pins except FAULTOUT and RETRY/TxD
VOL
—
0.4
V
Output low voltage (ILoad = 15 mA)
FAULTOUT and RETRY/TxD
VOL1
—
1.0
V
Input high voltage
All ports
VHi
0.7 x VDD
VDD
V
Input low voltage
All ports
VIL
VSS
0.3 x VDD
V
VDD supply current
IDD
—
60
mA
I/O ports high-impedance leakage current
IIL
—
±
µ$
Input current
IIn
—
±
µ$
Capacitance
Ports (as input or output)
C Out
C In
—
—
12
8
pF
VDD low-voltage inhibit reset
VLVR1
3.80
4.3
V
VDD low-voltage reset/recovery hysteresis
VLVH1
50
150
mV
VDD power-on reset re-arm voltage
VPOR
3.85
4.45
V
VDD power-on reset rise time ramp rate
RPOR
0.035
—
V/ms
Serial communications interface baud rate
SCIBD
9504
9696
Bits/sec
Voltage Boost(2)
VBoost
0
100
%
DTRange
0
31.875
µV
RTTime
0
4.55
Hours
Acceleration rate
ACRate
0.5
128
Hz/sec
Speed control
SPEED
1
128
Hz
PWMFREQ
5.291
21.164
kHz
TPump
99
101
ms
Output high voltage (ILoad = –2.0 mA)
All I/O pins except RBRAKE
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Output high voltage RBRAKE (IRBRAKE = –15.0 mA)
Dead time range (3)
Retry time
(4)
PWM Frequency
High side power transistor drive pump-up time
1. V DD = 5.0 Vdc ± 10%
2. Limited in standalone mode to 0 to 35%
3. Limited in standalone mode to 0.5 to 6.0 µV
4. Limited in standalone mode to 0 to ~53 seconds
6
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MC3PHAC/D
Pin Descriptions
Pin Descriptions
Table 2 is a pin-by-pin functional description of the MC3PHAC. The pin
numbers in the table refer to the 28-pin packages (see Figure 1).
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Table 2. MC3PHAC Pin Descriptions (Sheet 1 of 3)
Pin
Number
Pin Name
1
VREF
Pin Function
Reference voltage input for the on-chip ADC. For best signal-to-noise
performance, this pin should be tied to VDDA (analog).
2
RESET
A logic 0 on this pin forces the MC3PHAC to its initial startup state. All
PWM outputs are placed in a high-impedance mode. Reset is a
bidirectional pin, allowing a reset of the entire system. It is driven low
when an internal reset source is asserted (for example, loss of clock or
low VDD).
3
VDDA
Provides power for the analog portions of the MC3PHAC, which include
the internal clock generation circuit (PLL) and the ADC
4
VSSA
Returns power for the analog portions of the MC3PHAC, which include
the internal clock generation circuit (PLL) and the ADC
5
OSC2
Oscillator output used as part of a crystal or ceramic resonator clock
circuit.(1)
6
OSC1
Oscillator input used as part of a crystal or ceramic resonator clock
circuit. Can also accept a signal from an external canned oscillator.(1)
7
PLLCAP
A capacitor from this pin to ground affects the stability and reaction time
of the PLL clock circuit. Smaller values result in faster tracking of the
reference frequency. Larger values result in better stability. A value of
0.1 µF is typical.
8
PWMPOL_BASEFREQ
9
PWM_U_TOP
PWM output signal for the top transistor driving motor phase U
10
PWM_U_BOT
PWM output signal for the bottom transistor driving motor phase U
11
PWM_V_TOP
PWM output signal for the top transistor driving motor phase V
12
PWM_V_BOT
PWM output signal for the bottom transistor driving motor phase V
13
PWM_W_TOP
PWM output signal for the top transistor driving motor phase W
14
PWM_W_BOT
PWM output signal for the bottom transistor driving motor phase W
MOTOROLA
Input which is sampled at specific moments during initialization to
determine the PWM polarity and the base frequency (50 or 60 Hz)
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MC3PHAC/D
Table 2. MC3PHAC Pin Descriptions (Sheet 2 of 3)
Pin
Number
Pin Name
Pin Function
15
FAULTIN
A logic high on this input will immediately disable the PWM outputs. A
retry timeout interval will be initiated once this pin returns to a logic low
state.
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16
RETRY_TxD
In standalone mode, this pin is an output that drives low to indicate the
parameter mux input pin is reading an analog voltage to specify the time
to wait after a fault before re-enabling the PWM outputs. In PC master
software mode, this pin is an output that transmits UART serial data.
RBRAKE
Output which is driven to a logic high whenever the voltage on the dc bus
input pin exceeds a preset level, indicating a high bus voltage. This
signal is intended to connect a resistor across the dc bus capacitor to
prevent excess capacitor voltage.
DT_FAULTOUT
In standalone mode, this pin is an output which drives low to indicate the
parameter mux input pin is reading an analog voltage to specify the
dead-time between the on states of the top and bottom PWM signals for
a given motor phase. In PC master software mode, this pin is an output
which goes low whenever a fault condition occurs.
20
VBOOST_MODE
At startup, this input is sampled to determine whether to enter standalone
mode (logic high) or PC master software mode (logic low). In
standalone mode, this pin is also used as an output that drives low to
indicate the parameter mux input pin is reading an analog voltage to
specify the amount of voltage boost to apply to the motor.
21
VDD
+5-volt digital power supply to the MC3PHAC
22
VSS
Digital power supply ground return for the MC3PHAC
23
FWD
Input which is sampled to determine whether the motor should rotate in
the forward or reverse direction
24
START
Input which is sampled to determine whether the motor should be
running.
MUX_IN
In standalone mode, during initialization this pin is an output that is used
to determine PWM polarity and base frequency. Otherwise, it is an
analog input used to read several voltage levels that specify MC3PHAC
operating parameters.
17
18
19
25
8
PWMFREQ_RxD
In standalone mode, this pin is an output that drives low to indicate the
parameter mux input pin is reading an analog voltage to specify the
desired PWM frequency. In PC master software mode, this pin is an
input which receives UART serial data.
3-Phase AC Motor Controller
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Freescale Semiconductor, Inc.
MC3PHAC/D
Pin Descriptions
Table 2. MC3PHAC Pin Descriptions (Sheet 3 of 3)
Pin
Number
26
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27
28
Pin Name
Pin Function
SPEED
In standalone mode, during initialization this pin is an output that is used
to determine PWM polarity and base frequency. Otherwise, it is an
analog input used to read a voltage level corresponding to the desired
steady-state speed of the motor.
ACCEL
In standalone mode, during initialization this pin is an output that is used
to determine PWM polarity and base frequency. Otherwise, it is an
analog input used to read a voltage level corresponding to the desired
acceleration of the motor.
DC_BUS
In standalone mode, during initialization this pin is an output that is used
to determine PWM polarity and base frequency. Otherwise, it is an
analog input used to read a voltage level proportional to the dc bus
voltage.
1. Correct timing of the MC3PHAC is based on a 4.00 MHz crystal or ceramic resonator. Follow the crystal/resonator
manufacturer’s recommendations, as the crystal/resonator parameters determine the external component values required
for maximum stability and reliable starting. The load capacitance values used in the oscillator circuit design should include
all stray capacitances.
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MC3PHAC/D
Introduction
The MC3PHAC is a high-performance intelligent controller designed
specifically to meet the requirements for low-cost, variable-speed,
3-phase ac motor control systems. The device is adaptable and configurable,
based on its environment. Constructed with high-speed CMOS
(complementary metal-oxide semiconductor) technology, the MC3PHAC offers
a high degree of performance and ruggedness in the hostile environments
often found in motor control systems.
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The device consists of:
•
6-output pulse-width modulator (PWM)
•
4-channel analog-to-digital converter (ADC)
•
Phase-lock loop (PLL) based system oscillator
•
Low-power supply voltage detection circuit
•
Serial communications interface (SCI)
The serial communications interface is used in a mode, called PC master
software mode, whereby control of the MC3PHAC is from a host or master
personal computer executing PC master software or a microcontroller
emulating PC master software commands. In either case, control via the
internet is feasible.
Included in the MC3PHAC are protective features consisting of dc bus
monitoring and a system fault input that will immediately disable the PWM
module upon detection of a system fault.
Included motor control features include:
10
•
Open loop volts/Hertz speed control
•
Forward or reverse rotation
•
Start/stop motion
•
System fault input
•
Low-speed voltage boost
•
Internal power-on reset (POR)
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MC3PHAC/D
Features
Features
3-Phase Waveform Generation — The MC3PHAC generates six PWM
signals which have been modulated with variable voltage and variable
frequency information in order to control a 3-phase ac motor. A third harmonic
signal has been superimposed on top of the fundamental motor frequency to
achieve full bus voltage utilization. This results in a 15 percent increase in
maximum output amplitude compared to pure sine wave modulation.
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The waveform is updated at a 5.3 kHz rate (except when the PWM frequency
is 15.9 kHz), resulting in near continuous waveform quality. At 15.9 kHz, the
waveform is updated at 4.0 kHz.
DSP Filtering — A 24-bit IIR digital filter is used on the SPEED input signal in
standalone mode, resulting in enhanced speed stability in noisy environments.
The sampling period of the filter is 3 ms (except when the PWM frequency is
15.9 kHz) and it mimics the response of a single pole analog filter having a pole
at 0.4 Hz. At a PWM frequency of 15.9 kHz, the sampling period is 4 ms and
the pole is located at 0.3 Hz.
High Precision Calculations — Up to 32-bit variable resolution is employed
for precision control and smooth performance. For example, the motor speed
can be controlled with a resolution of 4 mHz.
Smooth Voltage Transitions — When the commanded speed of the motor
passes through ±1 Hz, the voltage is gently applied or removed depending on
the direction of the speed change. This eliminates any pops or surges that may
occur, especially under conditions of high-voltage boost at low frequencies.
High-Side Bootstrapping — Many motor drive topologies (especially highvoltage drives) use optocouplers to supply the PWM signal to the high-side
transistors. Often, the high-side transistor drive circuitry contains a charge
pump circuit to create a floating power supply for each high-side transistor that
is dependent on low-side PWMs to develop power. When the motor has been
off for a period of time, the charge on the high-side power supply capacitor is
depleted and must be replenished before proper PWM operation can resume.
To accommodate such topologies, the MC3PHAC will always provide 100 ms
of 50 percent PWM drive to only the low-side transistors each time the motor is
turned on. Since the top transistors remain off during this time, it has the effect
of applying zero volts to the motor, and no motion occurs. After this period,
motor waveform modulation begins, with PWM drive also being applied to the
high-side transistors.
Fast Velocity Updating — During periods when the motor speed is changing,
the rate at which the velocity is updated is critical to smooth operation. If these
updates occur too infrequently, a ratcheting effect will be exhibited on the
motor, which inhibits smooth torque performance. However, velocity profiling is
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MC3PHAC/D
a very calculation intensive operation to perform, which runs contrary to the
previous requirement.
In the MC3PHAC, a velocity pipelining technique is employed which allows
linear interpolation of the velocity values, resulting in a new velocity value every
189 µs (252 µs for 15.9 kHz PWMs). The net result is ultra smooth velocity
transitions, where each velocity step is not perceivable by the motor.
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Dynamic Bus Ripple Cancellation — The dc bus voltage is sensed by the
MC3PHAC, and any deviations from a predetermined norm (3.5 V on the
dc bus input pin) result in corrections to the PWM values to counteract the
effect of the bus voltage changes on the motor current. The frequency of this
calculation is sufficiently high to permit compensation for line frequency ripple,
as well as slower bus voltage changes resulting from regeneration or brown out
conditions. See Figure 4.
MOTOR PHASE CURRENT WAVEFORMS
REMOVES 60 Hz HUM
COMPENSATED
AND DECREASES I2R LOSSES
AC MAINS
UNCOMPENSATED
PWM1
PWM3
PWM5
PWM2
PWM4
PWM6
MC3PHAC
CORRECTED PWMs
Figure 4. Dynamic Bus Ripple Cancellation
12
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MC3PHAC/D
Features
Selectable Base Frequency — Alternating current (ac) motors are designed
to accept rated voltage at either 50 or 60 Hz, depending on what region of the
world they were designed to be used. The MC3PHAC can accommodate both
types of motors by allowing the voltage profile to reach maximum value at either
50 or 60 Hz. This parameter can be specified at initialization in standalone
mode, or it can be changed at any time in PC master software mode.
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Selectable PWM Polarity — The polarity of the PWM outputs may be specified
such that a logic high on a PWM output can either be the asserted or negated
state of the signal. In standalone mode, this parameter is specified at
initialization and applies to all six PWM outputs. In PC master software mode,
the polarity of the top PWM signals can be specified separately from the polarity
of the bottom PWM signals.
This specification can be done at any time, but once it is done, the polarities are
locked and cannot be changed until a reset occurs. Also, any commands from
PC master software that would have the effect of enabling PWMs are
prevented by the MC3PHAC until the polarity has been specified.
In standalone mode, the base frequency and PWM polarity are specified at the
same time during initialization by connecting either pin 25, 26, 27, or 28
exclusively to the PWMPOL_BASEFREQ input. During initialization, pins 25,
26, 27, and 28 are cycled one at a time to determine which one has been
connected to the PWMPOL_BASEFREQ input.
Table 3 shows the selected PWM polarity and base frequency as a function of
which pin connection is made. Refer to the standalone mode schematic,
Figure 8. Only one of these jumpers (JP1–JP4) can be connected at any one
time.
NOTE:
It is not necessary to break this connection once the initialization phase has
been completed. The MC3PHAC will function properly while this connection is
in place.
Table 3. PWM Polarity and Base Frequency
Specification in Standalone Mode
MOTOROLA
Pin Connected to
PWMPOL_BASEFREQ Pin
PWM Polarity
Base
Frequency
MUX_IN (JP1)
Logic low = on
50 Hz
SPEED (JP2)
Logic high = on
50 Hz
ACCEL (JP3)
Logic low = on
60 Hz
DC_BUS (JP4)
Logic high = on
60 Hz
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MC3PHAC/D
Selectable PWM Frequency — The MC3PHAC accommodates four discrete
PWM frequencies and can be changed dynamically while the motor is running.
This resistor can be a potentiometer or a fixed resistor in the range shown in
Table 4. In standalone mode, the PWM frequency is specified by applying a
voltage to the MUX_IN pin while the PWMFREQ_RxD pin is being driven low.
Table 4 shows the required voltage levels on the MUX_IN pin and the
associated PWM frequency for each voltage range.
NOTE:
The PWM frequencies are based on a 4.00 MHz frequency applied to the
oscillator input.
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Table 4. MUX_IN Resistance Ranges
and Corresponding PWM Frequencies
Voltage Input
PWM Frequency
0 to 1 V
5.291 kHz
1.5 to 2.25 V
10.582 kHz
2.75 to 3.5 V
15.873 kHz
4 to 5 V
21.164 kHz
Selectable PWM Dead Time — Besides being able to specify the PWM
frequency, the blanking time interval between the on states of the
complementary PWM pairs can also be specified. Refer to the graph in
Figure 9 for the resistance value versus dead time. Figure 9 assumes a
6.8 kΩ ±5% pullup resistor. In standalone mode, this is done by
supplying a voltage to the MUX_IN pin while the DT_FAULTOUT pin is being
driven low. In this way, dead time can be specified with a scaling factor of
2.075 µs per volt, with a minimum value of 0.5 µs. In PC master software mode,
this value can be selected to be anywhere between 0 and 32 µs.
In both standalone and PC master software modes, the dead time value can be
written only once. Further updates of this parameter are locked out until a reset
condition occurs.
Speed Control — The synchronous motor frequency can be specified in real
time to be any value from 1 Hz to 128 Hz by the voltage applied to the SPEED
pin. The scaling factor is 25.6 Hz per volt. This parameter can also be controlled
directly from PC master software in real time.
The SPEED pin is processed by a 24-bit digital filter to enhance the speed
stability in noisy environments. This filter is only activated in standalone mode.
Acceleration Control — Motor acceleration can be specified in real time to be
in the range from 0.5 Hz/second, ranging to 128 Hz/second, by the voltage
applied to the ACCEL pin. The scaling factor is 25.6 Hz/second per volt. This
parameter can also be controlled directly from PC master software in real time.
14
3-Phase AC Motor Controller
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MC3PHAC/D
Features
Voltage Profile Generation — The MC3PHAC controls the motor voltage in
proportion to the specified frequency, as indicated in Figure 5.
VOLTAGE
100%
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VOLTAGE BOOST
M
CO
AT
NS
PE
ION
TA
RS
FO
TO
OS
RL
S
SE
FREQUENCY
BASE FREQUENCY
Figure 5. Voltage Profiling, Including Voltage Boost
An ac motor is designed to draw a specified amount of magnetizing current
when supplied with rated voltage at the base frequency. As the frequency
decreases, assuming no stator losses, the voltage must decrease in exact
proportion to maintain the required magnetizing current. In reality, as the
frequency decreases, the voltage drop in the series stator resistance increases
in proportion to the voltage across the magnetizing inductance. This has the
effect of further reducing the voltage across the magnetizing inductor, and
consequently, the magnetizing current. A schematic representation of this
effect is illustrated in Figure 6. To compensate for this voltage loss, the voltage
profile is boosted over the normal voltage curve in Figure 5, so that the
magnetizing current remains constant over the speed range.
PARASITICS
X1
MAGNETIZING CURRENT
(TRY TO KEEP CONSTANT)
R1
X2
XM
R2
TORQUE CURRENT
R2 (1 –s)
s
Figure 6. AC Motor Single Phase Model
Showing Parasitic Stator Impedances
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MC3PHAC/D
The MC3PHAC allows the voltage boost to be specified as a percentage of full
voltage at 0 Hz, as shown in Figure 5. In standalone mode, voltage boost is
specified during the initialization phase by supplying a voltage to the MUX_IN
pin while the VBOOST_MODE pin is being driven low. Refer to the graph in
Figure 11 for the resistance value versus voltage boost. Figure 11 assumes a
6.8 kΩ pullup resistor. In this way, voltage boost can be specified from 0 to 40
percent, with a scaling factor of 8 percent per volt. In PC master software mode,
the voltage boost can be specified from 0 to 100 percent and can be changed
at anytime.
Freescale Semiconductor, Inc...
By using the voltage boost value, and the specified base frequency, the
MC3PHAC has all the information required to generate a voltage profile
automatically based on the generated waveform frequency. An additional
feature exists in PC master software mode whereby this voltage value can be
overridden and controlled in real time. Specifying a voltage lower than the
normal volts-per-hertz profile permits a softer torque response in certain
ergonomic situations. It also allows for load power factor control and higher
operating efficiencies with high inertia loads or other loads where
instantaneous changes in torque demand are not permitted. Details of this
feature are discussed in the PC Master Software Operation with the
MC3PHAC.
PLL Clock Generation — The OSC1 pin signal is used as a reference clock
for an internal PLL clocking circuit, which is used to drive the internal clocks of
the MC3PHAC. This provides excellent protection against noise spikes that
may occur on the OSC1 pin. In a clocking circuit that does not incorporate a
PLL, a noise spike on the clock input can create a clock edge, which violates
the setup times of the clocking logic, and can cause the device to malfunction.
The same noise spike applied to the input of a PLL clock circuit is perceived by
the PLL as a change in its reference frequency, and the PLL output frequency
begins to change in an attempt to lock on to the new frequency. However,
before any appreciable change can occur, the spike is gone, and the PLL
settles back into the true reference frequency.
Fault Protection — The MC3PHAC supports an elaborate range of fault
protection and prevention features. If a fault does occur, the MC3PHAC
immediately disables the PWMs and waits until the fault condition is cleared
before starting a timer to re-enable the PWMs. Refer to the graph in Figure 10
for the resistance value versus retry time. Figure 10 assumes a 6.8 kΩ pullup
resistor. In standalone mode, this timeout interval is specified during the
initialization phase by supplying a voltage to the MUX_IN pin while the
RETRY_TxD pin is being driven low. In this way, the retry time can be specified
from 1 to 60 seconds, with a scaling factor of 12 seconds per volt. In PC master
software mode, the retry time can be specified from 0.25 second to over
4.5 hours and can be changed at any time.
16
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MC3PHAC/D
Features
Freescale Semiconductor, Inc...
The fault protection and prevention features are:
•
External Fault Monitoring — The FAULTIN pin accepts a digital signal
that indicates a fault has been detected via external monitoring circuitry.
A high level on this input results in the PWMs being immediately
disabled. Typical fault conditions might be a dc bus over voltage, bus
over current, or over temperature. Once this input returns to a logic low
level, the fault retry timer begins running, and PWMs are re-enabled
after the programmed timeout value is reached.
•
Lost Clock Protection — If the signal on the OSC1 pin is lost
altogether, the MC3PHAC will immediately disable the PWM outputs to
protect the motor and power electronics. This is a special fault condition
in that it will also cause the MC3PHAC to be reset. Lost clock detection
is an important safety consideration, as many safety regulatory agencies
are now requiring a dead crystal test be performed as part of the
certification process.
•
Low VDD Protection — Whenever VDD falls below VLVR1, an on-board
power supply monitor will reset the MC3PHAC. This allows the
MC3PHAC to operate properly with 5 volt power supplies of either 5 or
10 percent tolerance.
•
Bus Voltage Integrity Monitoring — The DC_BUS pin is monitored at
a 5.3 kHz frequency (4.0 kHz when the PWM frequency is set to
15.9 kHz), and any voltage reading outside of an acceptable window
constitutes a fault condition. In standalone mode, the window thresholds
are fixed at 4.47 volts (128 percent of nominal), and 1.75 volts
(50 percent of nominal), where nominal is defined to be 3.5 volts. In PC
master software mode, both top and bottom window thresholds can be
set independently to any value between 0 volts (0 percent of nominal),
and greater than 5 volts (143 percent of nominal), and can be changed
at any time. Once the DC_BUS signal level returns to a value within the
acceptable window, the fault retry timer begins running, and PWMs are
re-enabled after the programmed timeout value is reached.
During power-up, it is possible that VDD could reach operating voltage
before the dc bus capacitor charges up to its nominal value. When the
dc bus integrity is checked, an under voltage would be detected and
treated as a fault, with its associated timeout period. To prevent this, the
MC3PHAC monitors the dc bus voltage during power-up in standalone
mode, and waits until it is higher than the under voltage threshold before
continuing. During this time, all MC3PHAC functions are suspended.
Once this threshold is reached, the MC3PHAC will continue normally,
with any further under voltage conditions treated as a fault.
If dc bus voltage monitoring is not desired, a voltage of
3.5 volts ± 5 percent should be supplied to the DC_BUS pin through an
impedance of between 4.7 kΩ and 15 kΩ.
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MC3PHAC/D
•
Regeneration Control — Regeneration is a process by which stored
mechanical energy in the motor and load is transferred back into the
drive electronics, usually as a result of an aggressive deceleration
operation. In special cases where this process occurs frequently (for
example, elevator motor control systems), it is economical to incorporate
special features in the motor drive to allow this energy to be supplied
back to the ac mains. However, for most low cost ac drives, this energy
is stored in the dc bus capacitor by increasing its voltage. If this process
is left unchecked, the dc bus voltage can rise to dangerous levels, which
can destroy the bus capacitor or the transistors in the power inverter.
Freescale Semiconductor, Inc...
The MC3PHAC incorporates two techniques to deal with regeneration
before it becomes a problem:
18
–
Resistive Braking — The DC_BUS pin is monitored at a
5.3 kHz frequency (4.0 kHz when the PWM frequency is set to
15.9 kHz), and when the voltage reaches a certain threshold, the
RBRAKE pin is driven high. This signal can be used to control a
resistive brake placed across the dc bus capacitor, such that
mechanical energy from the motor will be dissipated as heat in the
resistor versus being stored as voltage on the capacitor. In
standalone mode, the DC_BUS threshold required to assert the
RBRAKE signal is fixed at 3.85 volts (110 percent of nominal) where
nominal is defined to be 3.5 volts. In PC master software mode, this
threshold can be set to any value between 0 volts (0 percent of
nominal) and greater than 5 volts (143 percent of nominal) and can
be changed at any time.
–
Automatic Deceleration Control — When decelerating the motor, the
MC3PHAC attempts to use the specified acceleration value for
deceleration as well. If the voltage on the DC_BUS pin reaches a
certain threshold, the MC3PHAC begins to moderate the
deceleration as a function of this voltage, as shown in Figure 7. The
voltage range on the DC_BUS pin from when the deceleration
begins to decrease, to when it reaches 0, is 0.62 volts. In standalone
mode, the DC_BUS voltage where deceleration begins to decrease
is fixed at 3.85 volts (110 percent of nominal) where nominal is
defined to be 3.5 volts. In PC master software mode, this threshold
can be set to any value between 0 volts (0 percent of nominal) and
greater than 5 volts (143 percent of nominal) and can be changed at
any time.
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MC3PHAC/D
Digital Power Supply Bypassing
DECELERATION
ACCELERATION INPUT
BUS VOLTAGE
Freescale Semiconductor, Inc...
BEGIN MODERATING DECEL
(LEVEL IS PROGRAMMABLE
IN PC MASTER SOFTWARE MODE)
Figure 7. Deceleration as a Function of Bus Voltage
Digital Power Supply Bypassing
VDD and VSS are the digital power supply and ground pins for the MC3PHAC.
Fast signal transitions connected internally on these pins place high, shortduration current demands on the power supply. To prevent noise problems,
take special care to provide power supply bypassing at the VDD and VSS pins.
Place the bypass capacitors as close as possible to the MC3PHAC. Use a highfrequency-response ceramic capacitor, such as a 0.1 µF, paralleled with a bulk
capacitor in the range of 1 µF to 10 µF for bypassing the digital power supply.
Analog Power Supply Bypassing
VDDA and VSSA are the power supply pins for the analog portion of the clock
generator and analog-to-digital converter (ADC). On the schematics in this
document, analog ground is labeled with an A and other grounds are digital
grounds. Analog power is labeled as +5 A. It is good practice to isolate the
analog and digital +5 volt power supplies by using a small inductor or a low
value resistor less than 5 ohms in series with the digital power supply, to create
the +5 A supply. ADC VREF is the power supply pin used for setting the ADC’s
voltage reference.
Decoupling of these pins should be per the digital power supply bypassing,
described previously. ADC VREF (pin 1) and VDDA (pin 3) shall be connected
together and connected to the same potential as VDD.
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Freescale Semiconductor, Inc.
MC3PHAC/D
Freescale Semiconductor, Inc...
Grounding Considerations
Printed circuit board layout is an important design consideration. In particular,
ground planes and how grounds are tied together influence noise immunity. To
maximize noise immunity, it is important to get a good ground plane under the
MC3PHAC. It is also important to separate analog and digital grounds. That is
why, shown on the schematics, there are two ground designations, analog
ground is marked with an A and other grounds are digital grounds. GND is the
digital ground plane and power supply return. GNDA is the analog circuit
ground. They are both the same reference voltage, but are routed separately,
and tie together at only one point.
Power-Up/Power-Down
When power is applied or removed, it is important that the inverter’s top and
bottom output transistors in the same phase are not turned on simultaneously.
Since logic states are not always defined during power-up, it is important to
ensure that all power transistors remain off when the controller’s supply voltage
is below its normal operating level. The MC3PHAC’s PWM module outputs
make this easy by switching to a high impedance configuration whenever the
5-volt supply is below its specified minimum.
The user should use pullup or pulldown resistors on the output of the
MC3PHAC’s PWM outputs to ensure during power-up and power-down, that
the inverter’s drive inputs are at a known, turned off, state.
Operation
The MC3PHAC motor controller will operate in two modes. The first is
standalone operation, whereby the MC3PHAC can be used without any
intervention from an external personal computer. In standalone mode, the
MC3PHAC is initialized by passive devices connected to the MC3PHAC and
input to the system at power-up/reset time. In standalone mode, some
parameters continue to be input to the system as it operates. Speed, PWM
frequency, bus voltage, and acceleration parameters are input to the system on
a real-time basis.
The second mode of operation is called PC master software mode.That
operational mode requires the use of a personal computer and PC master
software executing on the personal computer, communicating with the
MC3PHAC, or a microcontroller emulating PC master software commands.
All command and setup information is input to the MC3PHAC via the PC host.
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MC3PHAC/D
Operation
Standalone Operation
If the VBOOST_MODE pin is high when the MC3PHAC is powered up, or after
a reset, the MC3PHAC enters standalone mode. In this mode of operation, the
functionality of many of the MC3PHAC pins change so that the device can
control a motor without requiring setup information from an external master.
When operated in standalone mode, the MC3PHAC will drive certain pins
corresponding to parameters which must be specified, while simultaneously
monitoring the response on other pins.
Freescale Semiconductor, Inc...
In many cases, the parameter to be specified is represented as an analog
voltage presented to the MUX_IN pin, while certain other pins are driven low.
In so doing, the MC3PHAC can accommodate an external analog mux which
will switch various signals on the MUX_IN pin when the signal select line goes
low. All signals must be in a range between 0 V and VREF. As an economical
alternative, an external passive network can be connected to each of the
parameter select output pins and the MUX_IN pin, as shown in Figure 8.
The Thevenin equivalent impedance of this passive network as seen by the
MUX_IN pin is very important and should be in the range of 5 kΩ to 10 kΩ. If
the resistance is too high, leakage current from the input/output (I/O) pins will
cause an offset voltage that will affect the accuracy of the reading. If the
resistance is too low, the parameter select pins will not be able to sink the
required current for an accurate reading. Using a pullup resistor value of 6.8 kΩ
(as indicated in Figure 8), the resulting value for each parameter as a function
of the corresponding pulldown resistor value is shown in Figure 9, Figure 10,
Figure 11, and Table 4.
The START input pin is debounced internally and a switch can be directly
accommodated on this pin. The input is level sensitive, but a logic 1 level must
exist on the pin before a logic 0 level will be processed as a start signal. This
will prevent an accidental motor startup in the event of the MC3PHAC being
powered up, where the switch was left in the start position.
The FWD input pin is debounced internally and can directly accommodate a
switch connection. The input is also level sensitive.
Figure 8 shows the jumper arrangement connected to the
PWMPOL_BASEFREQ input pin. For proper operation, one and only one
jumper connection can be made at any given time. Table 3 shows the polarity
and base frequency selections as a function of the jumper connection.
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Freescale Semiconductor, Inc.
MC3PHAC/D
+5 V
6.8 kΩ
NOTE 6
JP2
50 Hz + PWM POLARITY
JP3
60 Hz – PWM POLARITY
JP4
60 Hz + PWM POLARITY
FROM DIVIDED DC BUS
+5 A
10 kΩ
0.1 µF
1
2
3
4
A
22 pF
RESET
ACCEL
VDDA
SPEED
VSSA
MUX_IN
5 OSC2
4.0 MHz
22 pF
10 MΩ
DC_BUS 28
VREF
START
6
OSC1
0.1 µF
7
PLLCAP
NOTE 8
8
9
6 — PWMs TO
POWER STAGE
10
11
12
13
14
FWD
VSS
PWMPOL_BASEFREQ
VDD
PWM_U_TOP
VBOOST_MODE
PWM_U_BOT
DT_FAULTOUT
PWM_V_TOP
RBRAKE
PWM_V_BOT
RETRY/TxD
PWM_W_TOP
PWMFREQ/RxD
PWM_W_BOT
FAULTIN
A
27
5 kΩ
4.7 kΩ
26
+5 A
25
A
+5 V
10 kΩ
24
START/STOP
Freescale Semiconductor, Inc...
RESET
5 kΩ
4.7 kΩ
MC3PHAC
23
22
21
20
19
10 kΩ
+5
NOTE 7
+5
RBOOST
NOTE 1
RDEADTIME NOTE 2
18
17
16
FOR/REV
NOTE 7
+5 A
SPEED POT
50 Hz – PWM POLARITY
ACCELERATION POT
+5 V
JP1
TO RESISTIVE BRAKE DRIVER
RRETRY
RPWMFREQ
15
NOTE 3
NOTE 4
NOTE 5
FROM SYSTEM FAULT
DETECTION CIRCUIT
Notes:
1. See Figure 11.
2. See Figure 9.
3. See Figure 10.
4. See Table 4.
5. If no external fault circuit is provided, connect to VSS.
6. Connect only one jumper.
7. Use bypass capacitors placed close to the MC3PHAC.
8. Consult crystal/resonator manufacturer for component values.
Figure 8. Standalone MC3PHAC Configuration
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Freescale Semiconductor, Inc.
MC3PHAC/D
Operation
DEAD TIME (µs)
6.0
5.5
5.0
4.5
4.0
3.5
3.0
2.5
2.0
Freescale Semiconductor, Inc...
1.5
1.0
0.5
0
0
1
2
3
4
5
6
7
8
9
10
RESISTANCE (kΩ)
Figure 9. Dead Time as a Function of the RDEADTIME Resistor
RETRY TIME (SECONDS)
60
55
50
45
40
35
30
25
20
15
10
5
0
0
5
10
15
20
25
30
35
40
45
50
RESISTANCE (kΩ)
Figure 10. Fault Retry Time as a Function of the RRETRY Resistor
VBOOST (%)
40
35
30
25
20
15
10
5
0
0
5
10
15
20
25
30
35
40
45
50
RESISTANCE (kΩ)
Figure 11. Voltage Boost as a Function of the RBOOST Resistor
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MC3PHAC/D
Standalone Application Example
Freescale Semiconductor, Inc...
Figure 12 shows an application example of the MC3PHAC, configured in
standalone mode. Resistor values and jumpers have been selected to provide
the following performance:
1.
Base frequency of 60 Hz and positive PWM polarity (from Table 3)
2.
PWM frequency resistor 3.9 kΩ, which implies 10.582 kHz from
Table 4). (5v/(3.9k + 6.8k))*3.9k = 1.82 volts
3.
Dead-time resistor = 5.1 kΩ, which implies 4.5 µs (from Figure 9)
4.
Fault retry time resistor = 8.2 kΩ, which implies 32.8 seconds (from
Figure 10).
5.
Voltage boost resistor = 12 kΩ, which implies 25.5 percent (from
Figure 11).
6.
The wiper of the acceleration potentiometer is set at
2.5 V = 64 Hz/second acceleration rate (from the Acceleration Control
description on page 14.) The potentiometer, in this case, could have
been a resistor divider. If a resistor divider is used in place of the
acceleration potentiometer, keep the total resistance of the two resistors
less than 10 kΩ. Always use 4.7kΩ in series with the center of the
acceleration voltage divider resistors, connected to the ACCEL (pin 27)
as shown in the application example, Figure 12.
7.
Crystal/resonator capacitor values are typical values from the
manufacturer. Refer to the manufacturers data for actual values.
PC Master Software Operation
Introduction to PC Master Host Software
The MC3PHAC is compatible with Motorola’s PC master host software serial
interface protocol. Communication occurs over an on-chip UART, on the
MC3PHAC at 9600 baud to an external master device, which may be a
microcontroller that also has an integrated UART or a personal computer via a
COM port. With PC master software, an external controller can monitor and
control all aspects of the MC3PHAC operation.
When the MC3PHAC is placed in PC master software mode, all control of the
system is provided through the integrated UART, resident on the MC3PHAC.
Inputs such as START, FWD, SPEED, ACCEL, MUX_IN, and
PWMPOL_BASEFREQ have no controlling influence over operation of the
system. Even though the SPEED, START, and FWD inputs are disabled while
the system is in PC master software mode, through PC master software, it is
possible to monitor the state of those inputs.
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MC3PHAC/D
Operation
+5 V
6.8 kΩ
50 Hz – PWM POLARITY
NC
50 Hz + PWM POLARITY
NC
60 Hz – PWM POLARITY
60 Hz + PWM POLARITY
FROM DIVIDED DC BUS
0.1 µF
1
2
3
4
A
22 pF
10 MΩ
22 pF
DC_BUS 28
VREF
RESET
ACCEL
VDDA
SPEED
VSSA
MUX_IN
5 OSC2
START
6
OSC1
0.1 µF
7
PLLCAP
NOTE 7
8
9
6 — PWMs TO
POWER STAGE
10
11
12
13
14
5 kΩ
4.7 kΩ
MC3PHAC
FWD
VSS
PWMPOL_BASEFREQ
VDD
PWM_U_TOP
VBOOST_MODE
PWM_U_BOT
DT_FAULTOUT
PWM_V_TOP
RBRAKE
PWM_V_BOT
RETRY/TxD
PWM_W_TOP
PWMFREQ/RxD
PWM_W_BOT
FAULTIN
A
27
5 kΩ
4.7 kΩ
26
+5 A
25
A
+5 V
24
23
22
21
+5
RBOOST
20 12 kΩ
19
18
15
NOTE 1
RDEADTIME NOTE 2
5.1 kΩ
TO RESISTIVE BRAKE DRIVER
RRETRY
17 8.2 kΩ
16
10 kΩ
+5
NOTE 6
10 kΩ
START/STOP
RESET
4.0 MHz
Freescale Semiconductor, Inc...
NOTE 6
+5 A
SPEED POT
+5 A
10 kΩ
FOR/REV
+5 V
ACCELERATION POT
NC
RPWMFREQ
3.9 kΩ
NOTE 3
NOTE 4
NOTE 5
FROM SYSTEM FAULT
DETECTION CIRCUIT
Notes:
1. See Figure 11.
2. See Figure 9.
3. See Figure 10.
4. See Table 4.
5. If no external fault circuit is provided, connect to VSS.
6. Use bypass capacitors placed close to the MC3PHAC.
7. Consult crystal/resonator manufacturer for component values.
Figure 12. MC3PHAC Application Example in Standalone Mode
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Freescale Semiconductor, Inc.
MC3PHAC/D
The most popular master implementation is a PC, where a graphical user
interface (GUI) has been layered on top of the PC master software command
protocol, complete with a graphical data display, and an ActiveX interface.
Figure 13 shows the MC3PHAC configured in PC master software mode. It is
beyond the scope of this document to describe the PC master software protocol
or its implementation on a personal computer. For further information on these
topics, refer to other Motorola documents relating to the PC master software
protocol and availability of PC master host software.
Freescale Semiconductor, Inc...
+5 V
10 kΩ
NOTE 2
+5 A
1
RESET
0.1 µF
22 pF
4.0 MHz
10 MΩ
A
0.1 µF
RESET
VDDA
SPEED 26
4 V
SSA
25
NOTE 3
+5 V
8
9
10
6 — PWMs TO
POWER STAGE
MUX_IN
5 OSC2
6 OSC1
7
10 kΩ
DC_BUS 28
VREF
ACCEL 27
2
3
22 pF
MC3PHAC
11
START
FWD
VDD 21
DT_FAULTOUT
PWM_V_TOP
RBRAKE
12 PWM_V_BOT
13
14
PWM_W_TOP
PWM_W_BOT
560 Ω
22
PWMPOL_BASEFREQ
PWM_U_BOT
+5 V
23
VSS
VBOOST_MODE
10 kΩ
24
PLLCAP
PWM_U_TOP
FROM DIVIDED DC BUS
NOTE 2
FAULT LED
+5
20
19
18
RETRY/TxD 17 DATA TO PC
DATA FROM PC
16
PWMFREQ/RxD
15
NOTE 1
FAULTIN
TO RESISTIVE BRAKE DRIVER
ISOLATED
CONNECTION
OR NON-ISOLATED TO HOST
RS232 INTERFACE
FROM SYSTEM FAULT
DETECTION CIRCUIT
Notes:
1. If no external fault circuit is provided, connect to VSS.
2. Use bypass capacitors placed close to the MC3PHAC.
3. Consult crystal/resonator manufacturer for component values.
Figure 13. MC3PHAC Configuration for Using a PC as a Master
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Freescale Semiconductor, Inc.
MC3PHAC/D
Operation
PC Master Software Operation with the MC3PHAC
When power is first applied to the MC3PHAC, or if a logic low level is applied
to the RESET pin, the MC3PHAC enters PC master software mode if the
VBOOST_MODE pin is low during the initialization phase. The MC3PHAC
recognizes a subset of the PC master software command set, which is listed in
Table 5.
Table 5. Recognized PC Host Software Commands
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Command
Description
GETINFOBRIEF
MC3PHAC responds with brief summary of hardware setup
and link configuration information
READVAR8
MC3PHAC reads an 8-bit variable at a specified address
and responds with its value
READVAR16
MC3PHAC reads a 16-bit variable at a specified address
and responds with its value
READVAR32
MC3PHAC reads a 32-bit variable at a specified address
and responds with its value
WRITEVAR8
MC3PHAC writes an 8-bit variable at a specified address
WRITEVAR16
MC3PHAC writes a 16-bit variable at a specified address
With the READVARx commands, the addresses are checked for validity, and
the command is executed only if the address is within proper limits. In general,
a read command with an address value below $0060 or above $EE03 will not
execute properly, but instead will return an invalid operation response. An
exception to this rule is that PC master software allows reading locations
$0001, $0036 and $FE01, which are PORTB data register, Dead Time register
and SIM Reset Status registers respectively. The addresses for the
WRITEVARx commands are checked for validity, and the data field is also
limited to a valid range for each variable. See Table 6 for a list of valid data
values and valid write addresses.
User interface variables and their associated PC master software addresses
within the MC3PHAC are listed in Table 6.
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MC3PHAC/D
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Table 6. User Interface Variables for Use with PC Master Software
Name
Address
Read/
Write
Size
(Bytes)
Description
Valid Data
Commanded direction
$1000
W
1
Determines whether the motor should
go forward, reverse, or stop
Forward — $10
Reverse — $11
Stop — $20
Command reset
$1000
W
1
Forces the MC3PHAC to perform an
immediate reset
$30
1
Specifies the frequency of the
MC3PHAC PWM frequency
2
The modulus value supplied to the
PWM generator used by the
MC3PHAC — value is multiplied by
250 ns to obtain PWM period
1
Specifies the polarity of the MC3PHAC
PWM outputs. This is a write once
parameter after reset.
Example: $50 = Bottom and top PWM
outputs are positive polarity.
Commanded PWM
frequency(1)
Measured PWM
period
Commanded PWM
polarity(2), (3), (4)
$1000
$00A8
$1000
W
R
W
5.3 kHz — $41
10.6 kHz — $42
15.9 kHz — $44
21.1 kHz — $48
$00BD–$05E8
B + T + $50
B + T – $54
B – T + $58
B – T – $5C
Dead time
$0036
R/W
1
Specifies the dead time used by the
PWM generator.
Dead time = Value * 125 ns.
This is a write-once parameter.
Base frequency(3)
$1000
W
1
Specifies the motor frequency at which
full voltage is applied
60 Hz — $60
50 Hz — $61
Acceleration(3)
$0060
R/W
2
Acceleration in Hz/sec (7.9 format)(8)
$0000–$7FFF
Commanded motor
frequency(3)
$0062
R/W
2
Commanded frequency in Hz.
(8.8 format)(9)
$0000–$7FFF
Actual frequency
$0085
R
2
Actual frequency in Hz. (8.8 format)(9)
$0000–$7FFF
Status
$00C8
R
1
Status byte
$00–$FF
Voltage boost
$006C
R/W
1
0 Hz voltage.
%Voltage boost = Value/$FF
$00–$FF
$00–$FF
$00–$FF
(2), (3), (4)
(7)
Modulation index
$0091
R
1
Voltage level (motor waveform
amplitude percent assuming no bus
ripple compensation)
Modulation index = value/$FF
Maximum voltage
$0075
R/W
1
Maximum allowable modulation index
value
%Maximum voltage = value/$FF
VBus voltage(5), (10)
$0079
R
2
DC bus voltage reading
28
3-Phase AC Motor Controller
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$00–$FF
$000–$3FF
MOTOROLA
Freescale Semiconductor, Inc.
MC3PHAC/D
Operation
Table 6. User Interface Variables for Use with PC Master Software (Continued)
Freescale Semiconductor, Inc...
Name
Address
Read/
Write
Size
(Bytes)
Description
Valid Data
Fault timeout
$006A
R/W
2
Specifies the delay time after a fault
condition before re-enabling the
motor.
Fault timeout = value * 0.262 sec
Fault timer
$006D
R
2
Real-time display of the fault timer
Elapsed fault time = value * 0.262 sec
$0000–$FFFF
VBus decel value(10)
$00C9
R/W
2
VBus readings above this value result
in reduced deceleration.
$0000–$03FF
VBus RBRAKE
value(10)
$0064
R/W
2
VBus readings above this value result
in the RBRAKE pin being asserted.
$0000–$03FF
VBus brownout
value(10)
$0066
R/W
2
VBus readings below this value result in
an under voltage fault.
$0000–$03FF
VBus over voltage
value(10)
$0068
R/W
2
VBus readings above this value result
in an over voltage fault.
$0000–$03FF
Speed in ADC
value(5)
$0095
R
2
Left justified 10-bit ADC reading of the
SPEED input pin.
$0000–$FFC0
Setup(7)
$00AE
R
1
Bit field indicating which setup
parameters have been initialized
before motion is permitted
$E0–$FF
Switch in(7)
$0001
R
1
Bit field indicating the current state of
the start/stop and forward/reverse
switches
$00–$FF
Reset status(6), (7)
$FE01
R
1
Indicates cause of the last reset
$00–$FF
Version
$EE00
R
4
MC3PHAC version
$0000–$FFFF
ASCII field
1. The commanded PWM frequency cannot be written until the PWM outputs exit the high-impedance state. The default PWM
frequency is 15.873 kHz.
2. The PWM output pins remain in a high-impedance state until this parameter is specified.
3. This parameter must be specified before motor motion can be initiated by the MC3PHAC.
4. This is a write-once parameter. The first write to this address will execute normally. Further attempts at writing this
parameter will result in an illegal operation response from the MC3PHAC.
5. The value of this parameter is not valid until the PWM outputs exit the high-impedance state.
6. The data in this field is only valid for one read. Further reads will return a value of $00.
7. See register bit descriptions following this table.
8. Acceleration is an unsigned value with the upper seven bits range of $00 to $7F = acceleration value of 0 to
127 Hertz/second. The lower nine bits constitute the fractional portion of the acceleration parameter. Its range is $000 to
$1FF which equals 0 to ~1. Therefore, the range of acceleration is 0 to 127.99 Hertz/second.
9. Commanded motor frequency and actual frequency are signed values with the upper byte range of
$00 to $7F = frequency of 0 to 127 Hz. The lower byte is the fractional portion of the frequency. Its range is $00 to $FF
which equals 0 to ~1.
10. V Bus is the voltage value applied to the DC_BUS analog input pin. The analog-to-digital converter is a 10-bit converter with
a 5 volt full scale input. The value is equal to the voltage applied to the DC_BUS input pin/VREF * $03FF.
MOTOROLA
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Freescale Semiconductor, Inc.
MC3PHAC/D
Each bit variable listed in Table 6 is defined in Figure 14, Figure 15,
Figure 16, and Figure 17.
Address:
$00C8
Bit 7
6
5
4
3
SPEED
FORWARD
MOTOR
RESISTIVE
CHANGING MOTION ENERGIZED
BRAKE
Read:
2
1
Bit 0
EXTERNAL
FAULT
TRIP
OVERVOLTAGE
TRIP
UNDER
VOLTAGE
TRIP
U
0
0
Write:
Freescale Semiconductor, Inc...
Reset:
U
0
1
= Unimplemented
0
0
U = Unaffected
Figure 14. Status Register
SPEED CHANGING Bit
This read-only bit indicates if the motor is at a steady speed or if it is
accelerating or declerating.
1 = Motor is accelerating or decelerating.
0 = Motor is at a steady speed.
FORWARD MOTION Bit
This read-only bit indicates the direction of the motor. It also indicates if the
motor is stopped.
1 = Motor is rotating in the forward direction. If this bit is a logic 1 and the
actual frequency (location $0085 and $0086) is 0, the motor is
stopped.
0 = Motor is rotating in the reverse direction.
MOTOR ENERGIZED Bit
This read-only bit indicates PWM output activity
1 = All PWM outputs are active.
0 = The PWM outputs are inactive or the bottom PWM outputs are in the
pre-charge cycle.
RESISTIVE BREAK Bit
This read-only bit indicates the state of the RBRAKE output pin
1 = The RBRAKE output pin is active. Braking is in progress.
0 = The RBRAKE output pin is inactive and no braking is in progress.
30
3-Phase AC Motor Controller
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MOTOROLA
Freescale Semiconductor, Inc.
MC3PHAC/D
Operation
EXTERNAL FAULT TRIP Bit
This read-only bit indicates a FAULT has occurred resulting from a logic 1
applied to the FAULTIN pin.
1 = A logic 1 was applied to the FAULTIN pin and a FAULT timeout is still
in progress.
0 = A logic 0 is applied to the FAULTIN pin and no FAULT timeout is in
progress.
Freescale Semiconductor, Inc...
OVER-VOLTAGE TRIP Bit
This read-only bit indicates if the voltage at the DC_BUS pin exceeds the
preset value of VBus over voltage located at address $0068 and $0069.
1 = The voltage applied to the DC_BUS pin has exceeded the preset
value of VBus over voltage and a FAULT timeout is still in progress.
0 = The voltage applied to the DC_BUS pin is less than the preset value
of VBus over voltage and a FAULT timeout is not in progress.
UNDER-VOLTAGE Bit
This read-only bit indicates if the voltage at the DC_BUS pin is less than the
present value of VBus brownout located at address $0066 and $0067.
1 = The voltage applied to the DC_BUS pin is less than the present value
of VBus under voltage and a FAULT timeout is still in progress.
0 = The voltage applied to the DC-BUS pin is greater than the preset
value of VBus under voltage and a FAULT timeout is not in progress.
MOTOROLA
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Freescale Semiconductor, Inc.
MC3PHAC/D
Address:
$00AE
Bit 7
6
5
Read:
4
3
BASE
FREQUENCY
SET
SPEED
SET
0
0
2
1
Bit 0
ACCELER- POLARITY DEAD TIME
ATION SET
SET
SET
Write:
Reset:
1
1
1
0
0
0
= Unimplemented
Freescale Semiconductor, Inc...
Figure 15. Setup Register
BASE FREQUENCY SET Bit
This read-only bit indicates if the base frequency parameter has been set.
1 = Base frequency parameter has been set.
0 = Base frequency parameter has not been set.
SPEED SET Bit
This read-only bit indicates if the speed parameter has been set.
1 = Speed parameter has been set.
0 = Speed parameter has not been set.
ACCELERATION SET Bit
This read-only bit indicates if the acceleration rate parameter has been set.
1 = Acceleration rate parameter has been set.
0 = Acceleration rate parameter has not been set.
POLARITY SET Bit
This read-only bit indicates if the PWM polarity parameters has been set.
1 = PWM polarity parameters has been set.
0 = PWM polarity parameters has not been set.
DEAD TIME SET Bit
This read-only bit indicates if the dead time parameter has been set.
1 = Dead time parameter has been set.
0 = Dead time parameter has not been set.
32
3-Phase AC Motor Controller
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MOTOROLA
Freescale Semiconductor, Inc.
MC3PHAC/D
Operation
Address:
$0001
Bit 7
Read:
6
5
START/
STOP
FWD/
REVERSE
U
U
4
3
2
FAULT
OUT
RESISTOR
BRAKE
U
0
1
Bit 0
U
U
Write:
Reset:
U
= Unimplemented
U
U = Unaffected
Freescale Semiconductor, Inc...
Figure 16. Switch In Register
START/STOP Bit
This read-only bit indicates the state of the START input pin.
1 = The START input pin is at a logic 1.
0 = The START input pin is at a logic 0.
FWD/REVERSE Bit
This read-only bit indicates the state of the FWD input pin.
1 = The FWD input pin is at a logic 1
0 = The FWD input pin is at a logic 0
FAULT OUT Bit
This read-only bit indicates the state of the DT_FAULTOUT output pin.
1 = The DT_FAULTOUT output pin is indicating no fault condition.
0 = The DT_FAULTOUT output pin is indicating a fault condition.
RESISTIVE BRAKE Bit
This read-only bit indicates the state of resistive brake pin (RBRAKE).
1 = The RBRAKE output pin in active. Braking is in progress.
0 = The RBRAKE output pin in inactive and no braking is in progress.
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Freescale Semiconductor, Inc.
MC3PHAC/D
Address:
Read:
$FE01
Bit 7
6
POWER
UP
RESET
PIN
5
4
3
2
PC MASTER
MC3PHAC
MC3PHAC
SOFTWARE
FUNCTIONAL FUNCTIONAL
RESET
FAULT
FAULT
COMMAND
1
Bit 0
LOW VDD
VOLTAGE
Write:
Reset:
1
0
0
0
0
0
0
0
= Unimplemented
Freescale Semiconductor, Inc...
Figure 17. Reset Status Register
POWER UP Bit
This read-only bit indicates the last system reset was caused by the powerup reset detection circuit.
1 = The last reset was caused by an initial power-up of the MC3PHAC.
0 = Power-up reset was not the source of the reset or a read of the reset
status register after the first read.
RESET PIN Bit
This read-only bit indicates the last system reset was caused from the
RESET input pin.
1 = Last reset was caused by an external reset applied to the RESET
input pin.
0 = The RESET pin was not the source of the reset or a read of the reset
status register after the first read.
MC3PHAC FUNCTIONAL FAULT Bits
This read-only bit indicates if the last system reset was the result of an
internal system error.
1 = MC3PHAC internal system error
0 = The FUNCTIONAL FAULT was not the source of the reset or a read
of the reset status register after the first read.
PC MASTER SOFTWARE RESET COMMAND Bit
This read-only bit indicates the last system reset was the result of a PC
master software reset command.
1 = The MC3PHAC was reset by the PC master software command reset
as the result of a write of $30 to location $1000
0 = The PC master software RESET COMMAND was not the source of
the reset or a read of the reset status register after the first read.
LOW VDD VOLTAGE Bit
This read-only bit indicates if the last reset was the result of low VDD applied
to the MC3PHAC.
1 = The last reset was caused by the low power supply detection circuit.
0 = The LOW VDD was not the source of the reset or a read of the reset
status register after the first read.
34
3-Phase AC Motor Controller
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MOTOROLA
Freescale Semiconductor, Inc.
MC3PHAC/D
Operation
Command State Machine
When using the PC master software mode of operation, the command state
machine governs behavior of the device depending upon its current state,
system parameters, any new commands received via the communications link,
and the prevailing conditions of the system. The command state diagram is in
Figure 18. It illustrates the sequence of commands which are necessary to
bring the device from the reset condition to running the motor in a steady state
and depicts the permissible state transitions. The device will remain within a
given state unless the conditions shown for a transition are met.
Freescale Semiconductor, Inc...
Some commands only cause a temporary state change to occur. While they are
being executed, the state machine will automatically return to the state which
existed prior to the command being received. For example, the motor speed
may be changed from within any state by using the WRITEVAR16 command to
write to the "Speed In" variable. This will cause the "Set Speed" state to be
momentarily entered, the "Speed In" variable will be updated and then the
original state will be re-entered. This allows the motor speed, acceleration or
base frequency to be modified whether the motor is already accelerating,
decelerating, or in a steady state.
Each state is described here in more detail.
MOTOROLA
•
Reset — This state is entered when a device power-on reset (POR), pin
reset, loss of crystal, internally detected error, or reset command occurs
from within any state. In this state, the device is initialized and the PWM
outputs are configured to high impedance. This state is then
automatically exited.
•
PWMHighZ — This state is entered from the reset state. This state is
also re-entered after one and only one of the PWM dead-time or polarity
parameters have been initialized. In this state the PWM outputs are
configured to a high-impedance state as the device waits for both the
PWM dead time and polarity to be initialized.
•
SetDeadTime (write once) — This state is entered from the PWMHighZ
state the first time that a write to the PWM dead-time variable occurs. In
this state, the PWM dead time is initialized and the state is then
automatically exited. This state cannot be re-entered, and hence the
dead time cannot be modified, unless the reset state is first re-entered.
•
SetPolarity (write once) — This state is entered from the PWMHighZ
state the first time that the PWM polarity command is received. In this
state, the PWM polarity is initialized and the state is then automatically
exited. This state cannot be re-entered, and hence the polarity cannot
be modified, unless the reset state is first re-entered.
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Freescale Semiconductor, Inc.
MC3PHAC/D
CmdBaseFreqxx
from any state
CmdReset
Reset or
POR or
Loss of Crystal or
Internal Error
SetBaseFreq
Reset
Done
(return to
calling
state)
Initialized
W
WRITEVAR16:Acceleration
from any state
A
EV
RIT
e
t im
ade
:D
R8
SetDeadTime
(write once)
e
don
CmdPWMTxBx
Freescale Semiconductor, Inc...
SetAccel
SetPolarity
PWMHighZ
(write once)
done
Done
(return to
calling
state)
PWM dead-time set &
PWM polarity set
WRITEVAR16:Speed
In from any state
Other PC master software
command from any state
PWMOFF
SetSpeed
Execute PC
Master Cmd
PWM base freq. set &
Acceleration set &
Speed In set
Done
(return to
calling
state)
d& e
ove on
em out D
R
e
lt
Fauult Tim
Fa
Fault
Done
(return to
calling
state)
PWM0RPM
CmdFwd |
CmdRev
PWMPump
Done & CmdFwd
Done & CmdRev
=
CmdRev &
Actual speed = 0
CmdFwd &
Actual speed = 0
CmdRev |
CmdStop
FwdDecel
0
C
Ac mdS
tua top
ls &
pe
ed
=
0
p& d
to ee
dS l sp
Cmctua
A
Fault
CmdFwd |
CmdStop
FwdAccel
(S
Actual speed =
Speed In >
Cm pee
Speed In
Actual Speed
dR d I
ev n <
| C Ac
m tua
dS l
to s p e
FwdSteady
p
ed
)|
RevAccel
Speed In >
Actual Speed
RevDecel
|
d)
e
e
sp
al op
u
t t
Ac S
< md
n
C
I
d d|
ee Fw
p
(S md
C
Actual speed =
Speed In
RevSteady
Figure 18. PC Host Software Command State Diagram
36
3-Phase AC Motor Controller
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MOTOROLA
Freescale Semiconductor, Inc.
Freescale Semiconductor, Inc...
MC3PHAC/D
Operation
MOTOROLA
•
PWMOFF — This state is entered from the PWMHighZ state if both the
PWM dead time and polarity have been configured. In this state, the
PWM is activated and all the PWM outputs are driven off for the chosen
polarity. The device then waits for the PWM base frequency, motor
speed, and acceleration to be initialized.
•
PWM0RPM — This state is entered from the PWMOFF state when the
PWM base frequency, motor speed, and acceleration have been
initialized. This state can also be entered from the FwdDecel or
RevDecel states if a CmdStop command has been received, and the
actual motor speed has decelerated to 0 r.p.m. In this state, the PWM
pins are driven to the off state for the chosen polarity. The only exit of
this state is to the PWMPump state, which occurs when a CmdFwd or
CmdRev command is received.
•
PWMPump — This state is entered from the PWM0RPM state when a
CmdFwd or CmdRev command is received. In this state the top PWM
outputs are driven off while the bottom PWM outputs are driven with a
50 percent duty cycle. This allows high side transistor gate drive circuits
which require charge pumping from the lower transistors to be charged
up prior to applying full PWMs to energize the motor. This state is
automatically exited after the defined amount of time tPump (see
Electrical Characteristics).
•
FwdAccel — This state is entered from the PWMPump state after a
CmdFwd command is received and the timeout interval from the
PWMPump state is completed. This state can also be entered from the
FwdSteady state if the Speed In variable is increased above the actual
current speed and the RevDecel state if the actual motor speed equals
0 r.p.m. when a CmdFwd command has been received. In this state the
motor is accelerated forward according to the chosen parameters.
•
FwdSteady — This state is entered from the FwdAccel state after the
actual motor speed has reached the requested speed defined by the
Speed In variable. In this state, the motor is held at a constant forward
speed.
•
FwdDecel — This state is entered from the FwdAccel or FwdSteady
states whenever a CmdStop or CmdRev command is received. This
state can also be entered from the FwdSteady state if the Speed In
variable is decreased below the actual current speed. In this state, the
motor is decelerated forward according to the chosen parameters.
•
RevAccel — This state is entered from the PWMPump state. After a
CmdRev command is received and the timeout interval from the
PWMPump state is completed. This state can also be entered from the
RevSteady state if the Speed In variable is increased above the actual
current speed and the FwdDecel state if the actual motor speed equals
0 r.p.m. when a CmdRev command has been received. In this state, the
motor is accelerated in reverse according to the chosen parameters.
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Freescale Semiconductor, Inc.
Freescale Semiconductor, Inc...
MC3PHAC/D
38
•
RevSteady — This state is entered from the RevAccel state after the
actual motor speed has reached the requested speed defined by the
Speed In variable. In this state, the motor is held at a constant reverse
speed.
•
RevDecel — This state is entered from the RevAccel or RevSteady
states whenever a CmdStop or CmdFwd command is received. This
state can also be entered from the RevSteady state if the Speed In
variable is decreased below the actual current speed. In this state, the
motor is decelerated in reverse according to the chosen parameters.
•
SetBaseFreq — This state is entered from any state whenever a
CmdBaseFreqxx command is received. In this state, the motor
frequency at which full voltage is applied is configured and the state is
then automatically exited and the original state is re-entered.
•
SetAccel — This state is entered from any state whenever a write to the
Acceleration variable occurs. In this state, the motor acceleration is
configured and the state is then automatically exited and the original
state is re-entered.
•
SetSpeed — This state is entered from any state whenever a write to
the Speed In variable occurs. In this state, the requested motor speed is
configured and the state is then automatically exited and the original
state is re-entered.
•
Fault — This state is entered from any state whenever a fault condition
occurs (see Fault Protection on page 16). In this state, the PWM
outputs are driven off (unless the fault state was entered from the
PWMHighZ state, in which case, the PWM outputs remain in the High Z
state). When the problem causing the fault condition is removed, a timer
is started which will wait a specified amount of time (which is user
programmable) before exiting this state. Under normal operating
conditions, this timeout will cause the Fault state to be automatically
exited to the PWM0RPM state, where motion will once again be initiated
if a CmdFwd or CmdRev has been received. The exceptions to this rule
are the cases when the Fault state was entered from the PWMHighZ or
PWMOFF states, in which case, exiting from the Fault state will return
back to these states.
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MOTOROLA
Freescale Semiconductor, Inc.
MC3PHAC/D
Optoisolated RS232 Interface Application Example
Optoisolated RS232 Interface Application Example
Freescale Semiconductor, Inc...
Some motor control systems have the control electronics operating at the same
potential as the high voltage bus. Connecting a PC to that system could present
safety issues, due to the high voltage potential between the motor control
system and the PC. Figure 19 is an example of a simple circuit that can be
used with the MC3PHAC to isolate the serial port of the PC from the motor
control system.
The circuit in Figure 19 is the schematic of a half-duplex optoisolated RS232
interface. This isolated terminal interface provides a margin of safety between
the motor control system and a personal computer. The EIA RS232
specification states the signal levels can range from ±3 to ±25 volts. A Mark is
defined by the EIA RS232 specification as a signal that ranges from –3 to –25
volts. A Space is defined as a signal that ranges from +3 to +25 volts.
Therefore, to meet the RS232 specification, signals to and from a terminal must
transition through 0 volts as it changes from a Mark to a Space. Breaking the
circuit down into an input and output section simplifies the explanation of the
circuit.
D1
1N4148
D2
1N4148
J1
5
9
4
8
3
7
2
6
1
CON/CANNON9
FEMALE
GND
DTR
TxD
RTS
RxD
R1
1 kΩ
D3
1N4148
R3
4.7 kΩ
+5 V
U1
4N35
1
4
2
5
R2
1 kΩ
TO MC3PHAC PIN 16
+
C1
2.2 µF/50 V
4
1
R4
330 Ω
5
~+12 V
U2
4N35
2
+5 V
TO MC3PHAC PIN 17
ISOLATION BARRIER
RS232 ISOLATED
HALF-DUPLEX, MAXIMUM 9600 BAUD
Figure 19. Optoisolated RS232 Circuit
MOTOROLA
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Freescale Semiconductor, Inc.
MC3PHAC/D
Freescale Semiconductor, Inc...
To send data from a PC to the MC3PHAC, it is necessary to satisfy the serial
input of the MC3PHAC. In the idle condition, the serial input of the MC3PHAC
must be at a logic 1. To accomplish that, the transistor in U1 must be turned off.
The idle state of the transmit data line (TxD) from the PC serial port is a Mark
(–3 to –25 volts). Therefore, the diode in U1 is off and the transistor in U1 is off,
yielding a logic 1 to the MC3PHAC’s serial input. When the start bit is sent to
the MC3PHAC from the PC’s serial port, the PC’s TxD transitions from a Mark
to a Space (+3 to +25 volts), thus forward biasing the diode in U1. Forward
biasing the diode in D1 turns on the transistor in U1, providing a logic 0 to the
serial input of the MC3PHAC. Simply stated, the input half of the circuit
provides input isolation, signal inversion, and level shifting from the PC to the
MC3PHAC’s serial port. An RS-232 line receiver, such as an MC1489, serves
the same purpose without the optoisolation function.
To send data from the MC3PHAC to the PC’s serial port input, it is necessary
to satisfy the PC’s receive data (RxD) input requirements. In an idle condition,
the RxD input to the PC must be at Mark (–3 to –25 volts). The data terminal
ready output (DTR) on the PC outputs a Mark when the port is initialized. The
request to send (RTS) output is set to a Space (+3 to +25 volts) when the PC’s
serial port is initialized. Because the interface is half-duplex, the PC’s TxD
output is also at a Mark, as it is idle. The idle state of the MC3PHAC’s serial
port output is a logic 1. The logic 1 out of the MC3PHAC’s serial port output port
forces the diode in U2 to be turned off. With the diode in U2 turned off, the
transistor in U2 is also turned off. The junction of D2 and D3 are at a Mark (–3
to –25 volts). With the transistor in U2 turned off, the input is pulled to a Mark
through current limiting resistor R3, satisfying the PC’s serial input in an idle
condition. When a start bit is sent from the MC3PHAC’s serial port, it transitions
to a logic 0. That logic 0 turns on the diode in U2, thus turning on the transistor
in U2. The conducting transistor in U2 passes the voltage output from the PC’s
RTS output, that is now at a Space (+3 to +25 volts), to the PC’s receive data
(RxD) input. Capacitor C1 is a bypass capacitor used to stiffen the Mark signal.
The output half of the circuit provides output isolation, signal inversion, and
level shifting from the MC3PHAC’s serial output port to the PC’s serial port. An
RS-232 line driver, such as a MC1488, serves the same purpose without the
optoisolation function.
Mechanical Data
This subsection provides case outline drawings for:
40
•
Plastic 28-pin DIP, Figure 20
•
Plastic 28-pin SOIC, Figure 21
•
Plastic 32-pin QFP, Figure 22
3-Phase AC Motor Controller
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MOTOROLA
Freescale Semiconductor, Inc.
MC3PHAC/D
Mechanical Data
28
NOTES:
1. POSITIONAL TOLERANCE OF LEADS (D),
SHALL BE WITHIN 0.25mm (0.010) AT
MAXIMUM MATERIAL CONDITION, IN
RELATION TO SEATING PLANE AND
EACH OTHER.
2. DIMENSION L TO CENTER OF LEADS
WHEN FORMED PARALLEL.
3. DIMENSION B DOES NOT INCLUDE
MOLD FLASH.
15
B
1
14
A
DIM
A
B
C
D
F
G
H
J
K
L
M
N
L
C
Freescale Semiconductor, Inc...
N
H
G
F
M
K
D
J
SEATING
PLANE
MILLIMETERS
MIN
MAX
36.45 37.21
13.72 14.22
3.94
5.08
0.36
0.56
1.02
1.52
2.54 BSC
1.65
2.16
0.20
0.38
2.92
3.43
15.24 BSC
0°
15°
0.51
1.02
INCHES
MIN
MAX
1.435 1.465
0.540 0.560
0.155 0.200
0.014 0.022
0.040 0.060
0.100 BSC
0.065 0.085
0.008 0.015
0.115 0.135
0.600 BSC
0°
15°
0.020 0.040
Figure 20. Plastic 28-Pin DIP (Case 710)
-A28
NOTES:
1. DIMENSIONING AND TOLERANCING PER
ANSI Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DIMENSION A AND B DO NOT INCLUDE MOLD
PROTRUSION.
4. MAXIMUM MOLD PROTRUSION 0.15
(0.006) PER SIDE.
5. DIMENSION D DOES NOT INCLUDE
DAMBAR PROTRUSION. ALLOWABLE
DAMBAR PROTRUSION SHALL BE 0.13
(0.005) TOTAL IN EXCESS OF D
DIMENSION AT MAXIMUM MATERIAL
CONDITION.
15
14X
-B1
P
0.010 (0.25)
M
B
M
14
28X D
0.010 (0.25)
M
T
A
S
B
M
S
R X 45°
C
-T26X
-T-
G
K
SEATING
PLANE
F
J
DIM
A
B
C
D
F
G
J
K
M
P
R
MILLIMETERS
MIN
MAX
17.80 18.05
7.60
7.40
2.65
2.35
0.49
0.35
0.90
0.41
1.27 BSC
0.32
0.23
0.29
0.13
8°
0°
10.05 10.55
0.75
0.25
INCHES
MIN
MAX
0.701 0.711
0.292 0.299
0.093 0.104
0.014 0.019
0.016 0.035
0.050 BSC
0.009 0.013
0.005 0.011
8°
0°
0.395 0.415
0.010 0.029
Figure 21. Plastic 28-Pin SOIC (Case 751F)
MOTOROLA
3-Phase AC Motor Controller
For More Information On This Product,
Go to: www.freescale.com
41
Freescale Semiconductor, Inc.
A
–T–, –U–, –Z–
MC3PHAC/D
4X
A1
32
0.20 (0.008) AB T–U Z
25
1
–U–
–T–
B
V
AE
P
B1
DETAIL Y
17
8
V1
AE
DETAIL Y
9
4X
Freescale Semiconductor, Inc...
–Z–
9
0.20 (0.008) AC T–U Z
S1
S
DETAIL AD
G
–AB–
0.10 (0.004) AC
AC T–U Z
–AC–
BASE
METAL
ÉÉ
ÉÉ
ÉÉ
ÉÉ
F
8X
M_
R
J
M
N
D
0.20 (0.008)
SEATING
PLANE
SECTION AE–AE
W
K
X
DETAIL AD
Q_
GAUGE PLANE
H
0.250 (0.010)
C E
NOTES:
1. DIMENSIONING AND TOLERANCING PER ANSI
Y14.5M, 1982.
2. CONTROLLING DIMENSION: MILLIMETER.
3. DATUM PLANE –AB– IS LOCATED AT BOTTOM
OF LEAD AND IS COINCIDENT WITH THE LEAD
WHERE THE LEAD EXITS THE PLASTIC BODY AT
THE BOTTOM OF THE PARTING LINE.
4. DATUMS –T–, –U–, AND –Z– TO BE DETERMINED
AT DATUM PLANE –AB–.
5. DIMENSIONS S AND V TO BE DETERMINED AT
SEATING PLANE –AC–.
6. DIMENSIONS A AND B DO NOT INCLUDE MOLD
PROTRUSION. ALLOWABLE PROTRUSION IS
0.250 (0.010) PER SIDE. DIMENSIONS A AND B
DO INCLUDE MOLD MISMATCH AND ARE
DETERMINED AT DATUM PLANE –AB–.
7. DIMENSION D DOES NOT INCLUDE DAMBAR
PROTRUSION. DAMBAR PROTRUSION SHALL
NOT CAUSE THE D DIMENSION TO EXCEED
0.520 (0.020).
8. MINIMUM SOLDER PLATE THICKNESS SHALL BE
0.0076 (0.0003).
9. EXACT SHAPE OF EACH CORNER MAY VARY
FROM DEPICTION.
DIM
A
A1
B
B1
C
D
E
F
G
H
J
K
M
N
P
Q
R
S
S1
V
V1
W
X
MILLIMETERS
MIN
MAX
7.000 BSC
3.500 BSC
7.000 BSC
3.500 BSC
1.400
1.600
0.300
0.450
1.350
1.450
0.300
0.400
0.800 BSC
0.050
0.150
0.090
0.200
0.500
0.700
12_ REF
0.090
0.160
0.400 BSC
1_
5_
0.150
0.250
9.000 BSC
4.500 BSC
9.000 BSC
4.500 BSC
0.200 REF
1.000 REF
INCHES
MIN
MAX
0.276 BSC
0.138 BSC
0.276 BSC
0.138 BSC
0.055
0.063
0.012
0.018
0.053
0.057
0.012
0.016
0.031 BSC
0.002
0.006
0.004
0.008
0.020
0.028
12_ REF
0.004
0.006
0.016 BSC
1_
5_
0.006
0.010
0.354 BSC
0.177 BSC
0.354 BSC
0.177 BSC
0.008 REF
0.039 REF
Figure 22. Plastic 32-Pin QFP (Case 873A)
42
3-Phase AC Motor Controller
For More Information On This Product,
Go to: www.freescale.com
MOTOROLA
Freescale Semiconductor, Inc.
Freescale Semiconductor, Inc...
MC3PHAC/D
Mechanical Data
MOTOROLA
3-Phase AC Motor Controller
For More Information On This Product,
Go to: www.freescale.com
43
Freescale Semiconductor, Inc.
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1-303-675-2140 or 1-800-441-2447
JAPAN:
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3-20-1, Minami-Azabu Minato-ku, Tokyo 106-8573 Japan
81-3-3440-3569
Freescale Semiconductor, Inc...
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852-26668334
TECHNICAL INFORMATION CENTER:
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MC3PHAC/D
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