TOSHIBA TB6548F

TB6548F
TOSHIBA CMOS Integrated Circuit Silicon Monolithic
TB6548F
3-Phase Full-Wave PWM Sensorless Controller for Brushless DC Motors
TB6548F is a 3-phase full-wave sensorless controller for
brushless DC motors. It is capable of controlling voltage by PWM
signal input. It is capable of PWM type sensorless driving when
used conjunction with TA84005F
Features
•
3-phase full-wave sensorless drive
•
PWM control (PWM signal is supplied from external sources.)
•
Turn-on signal output current: 20 mA
•
Built-in protection against overcurrent
•
Forward/reverse modes
•
Built-in lead angle control function (0, 7.5, 15 and 30 degrees)
•
Built-in lap turn-on function
Weight: 0.32 g (typ.)
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TB6548F
Block Diagram
VDD
FG_OUT
13
6
14 OUT_UP
PWM 3
PWM Control
17 OUT_VP
SEL_LAP 8
CW_CCW 4
Rotation
Instruction
Circuit
Turn-on Signal
Forming Circuit
Timing
Control
21 OUT_WP
15 OUT_UN
19 OUT_VN
22 OUT_WN
LA0 1
LA1 2
Lead Angle
Setting Circuit
Overcurrent
Protection
Circuit
Clock
Generator
Circuit
Position
Detection
Circuit
10
11
12
XT
XTin
GND
23 OC
24 WAVE
Pin Assignment
LA0
1
24
WAVE
LA1
2
23
OC
PWM
3
22
OUT_WN
CW_CCW
4
21
OUT_WP
NC
5
20
NC
FG_OUT
6
19
OUT_VN
NC
7
18
NC
SEL_LAP
8
17
OUT_VP
NC
9
16
NC
XT
10
15
OUT_UN
XTin
11
14
OUT_UP
GND
12
13
VDD
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TB6548F
Pin Description
Pin No.
Symbol
I/O
1
LA0
I
Description
Lead angle setting signal input pin
2
LA1
I
•
LA0 = Low, LA1 = Low: Lead angle 0 degree
•
LA0 = High, LA1 = Low: Lead angle 7.5 degree
•
LA0 = Low, LA1 = High: Lead angle 15 degree
•
LA0 = High, LA1 = High: Lead angle 30 degree
•
Built-in pull-down resistor
PWM signal input pin
3
PWM
I
•
Inputs Low-active PWM signal
•
Built-in pull-up resistor
•
Disables input of duty-100% (Low) signal
High for 250 ns or longer is required.
Rotation direction signal input pin
4
CW_CCW
I
5
NC

6
FG_OUT
O
7
NC

•
High: Reverse (U → W → V)
•
Low, Open: Forward (U → V → W)
•
Built-in pull-down resistor
Not connected
Number of ratation detection signal output pin
•
Equiralent to U-phase signal (except PWM)
Not connected
Lap turn-on select pin
8
SEL_LAP
I
•
Low: Lap turn-on
•
High: 120 degrees turn-on
•
Built-in pull-up resistor
9
NC

Not connected
10
XT

Resonator connecting pin
11
XTin

12
GND

Connected to GND.
13
VDD

Connected to 5-V power supply.
•
Selects starting commutation frequency.
17
Starting commutation frequency fst = Resonator frequency fxt/(6 × 2 )
U-phase upper turn-on signal output pin
14
OUT_UP
O
•
U-phase winding wire positive ON/OFF switching pin
•
ON: Low, OFF: High
U-phase lower turn-on signal output pin
15
OUT_UN
O
16
NC

17
OUT_VP
O
•
U-phase winding wire negative ON/OFF switching pin
•
ON: High, OFF: Low
Not connected
V-phase upper turn-on signal output pin
18
NC

19
OUT_VN
O
•
V-phase winding wire positive ON/OFF switching pin
•
ON: Low, OFF: High
Not connected
V-phase lower turn-on signal output pin
20
NC

•
V-phase winding wire negative ON/OFF switching pin
•
ON: High, OFF: Low
Not connected
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TB6548F
Pin No.
Symbol
I/O
21
OUT_WP
O
Description
W-phase upper turn-on signal output pin
•
W-phase winding wire positive ON/OFF switching pin
•
ON: Low, OFF: High
W-phase lower turn-on signal output pin
22
OUT_WN
O
•
W-phase winding wire negative ON/OFF switching pin
•
ON: High, OFF: Low
Overcurrent signal input pin
23
OC
I
•
High on this pin can put constraints on the turn-on signal which is performing PWM
control.
•
Built-in pull-up resistor
Positional signal input pin
24
WAVE
I
•
Inputs majority logic synthesis signal of three-phase pin voltage.
•
Built-in pull-up resistor
Functional Description
1. Sensorless Drive
On receipt of PWM signal start instruction turn-in signal for forcible commutation (commutation
irrespective of the motor’s rotor position) is output and the motor starts to rotate. The motor’s rotation
causes induced voltage on winding wire pin for each phase.
When signals indicating positive or negative for pin voltage (including induced voltage) for each phase
are input on respective positional signal input pin, the turn-on signal for forcible commutation is
automatically switched to turn-on signal for positional signal (induced voltage).
Thereafter turn-on signal is formed according to the induced voltage contained in the pin voltage so as to
drive the brushless DC motor.
2. Starting commutation frequency (resonator pin and counter bit select pin)
The forcible commutation frequency at the time of start is determined by the resonator’s frequency and
the number of counter bit (within the IC).
+
Starting commutation frequency fst = Resonator frequency fxt/(6 × 2 (bit 3))
bit = 14
The forcible commutation frequency at the time of start can be adjusted using inertia of the motor and
load.
• The forcible commutation frequency should be set higher as the number of magnetic poles increases.
• The forcible commutation frequency should be set lower as the inertia of the load increases.
3. PWM Control
PWM signal can be reflected in turn-on signal by supplying PWM signal from external sources.
The frequency of the PWM signal shoud be set adequately high with regard to the electrical frequency of
the motor and in accordance to the switching characteristics of the drive circuit.
Because positional detection is performed in synchronization with the falling edges of PWM signal,
positional detection cannot be performed with 0% duty or 100% duty.
Duty (max)
250 ns
Duty (min)
250 ns
The voltage applied to the motor is duty 100% because of the storage time of the drive circuit even if the
duty is 99%.
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TB6548F
4. PWM Control
Upper turn-on
signal (OUT-P)
Lower turn-on
signal (OUT-N)
Output
voltage
of TA84005F
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TB6548F
5. Positional Variation
Since positional detection is performed in synchronization with PWM signal, positional variation occurs
in connection with the frequency of PWM signal. Be especially careful when the IC is used for high-speed
motors.
PWM signal
Output voltage
of TA84005F
Reference voltage
Pin voltage
Positional signal
Ideal detection timing
Actual detection timing
Variation is calculated by detecting at two consecutive rising edges of PWM signal.
1/fp < Detection time variation < 2/fp
fp: PWM frequency
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6. Lead Angle Control
The lead angle is 0 degree during the starting forcible commutation and when normal commutation is
started, automatically changes to the lead angle which has been set using LA0 and LA1. However, if both
LA0 and LA1 are set for High, the lead angle is 30 degrees in the starting forcible commutation as well as
in normal commutation.
Induced voltage
Turn-on signal
(1) Lead angle: 0 degree
U
V
W
30 degrees
OUT_UP
OUT_UN
PWM control
OUT_VP
OUT_VN
OUT_WP
OUT_WN
(2) Lead angle: 7.5 degrees
PWM control
22.5 degrees
OUT_UP
OUT_UN
PWM control
OUT_VP
OUT_VN
PWM control
OUT_WP
OUT_WN
(3) Lead angle: 15 degree
PWM control
15 degrees
OUT_UP
OUT_UN
OUT_VP
OUT_VN
PWM control
OUT_WP
OUT_WN
PWM control
(4) Lead angle: 30 degree
OUT_UP
OUT_UN
PWM control
OUT_VP
OUT_VN
OUT_WP
OUT_WN
PWM control
PWM control
7. Lap Turn-on Control
When SEL_LAP = High, the turn-on degree is 120 degrees. When SEL_LAP = Low, Lap Turn-on Mode
starts.
In Lap Turn-on Mode, the time between zero-cross point and the 120 degrees turn-on timing becomes
longer (shaded area in the below chart) so as to create some overlap when switching turn on signals. The
lap time differs depending ong the lead angle setting.
Induced voltage
Turn-on signal
U
V
W
(1) Lead angle: 0 degree
OUT_UP
OUT_UN
PWM control
OUT_VP
OUT_VN
OUT_WP
OUT_WN
PWM control
(2) Lead angle: 7.5 degrees
OUT_UP
OUT_UN
PWM control
OUT_VP
OUT_VN
PWM control
OUT_WP
OUT_WN
PWM control
(3) Lead angle: 15 degree
OUT_UP
OUT_UN
OUT_VP
OUT_VN
PWM control
OUT_WP
OUT_WN
PWM control
(4) Lead angle: 30 degree
OUT_UP
OUT_UN
PWM control
OUT_VP
OUT_VN
OUT_WP
OUT_WN
PWM control
PWM control
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TB6548F
8. Start/Stop Control
Start/Stop is controlled using PWM signal input pin.
A stop is acknowledged when PWM signal duty is 0, and a start is acknowledged when ON-signal of a
frequency 4 times higher than the resonator frequency or even higher is input continuously.
Timing chart
PWM signal
Detection
timing
Start
512 periods at the resonator frequency
Second detection
First detection
Start
PWM signal
Detection
timing
Stop
512 periods at the resonator frequency
First detection
Second detection
and stop
Note: Take sufficient care for noise on PWM signal input pin.
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TB6548F
Maximum Ratings (Ta = 25°C)
Characteristics
Symbol
Rating
Unit
Power supply voltage
VDD
5.5
V
Input voltage
Vin
−0.3 to VDD + 0.3
V
IOUT
20
mA
Turn-on signal output current
Power dissipation
PD
590
mW
Operating temperature
Topr
−30 to 85
°C
Storage temperature
Tstg
−55 to 150
°C
Recommended Operating Conditions (Ta = −30 to 85°C)
Characteristics
Symbol
Test Condition
Min
Typ.
Max
Unit
Power supply voltage
VDD

4.5
5.0
5.5
V
Input voltage
Vin

−0.3

VDD
+ 0.3
V
fPWM


16

kHz
fosc

1.0

10
MHz
PWM frequency
Oscillation frequency
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TB6548F
Electrical Characteristics (Ta = 25°C, VDD = 5 V)
Characteristics
Static power supply current
Dynamic power supply current
Input current
Symbol
Test
Circuit
IDD

IDD (opr)
Min
Typ.
Max
Unit
PWM = H, XTin = H

0.1
0.3
mA

PWM = 50% Duty, XTin = 4 MHz

1
3
mA
IIN-1 (H)

VIN = 5 V, PWM, OC, WAVE_U,
SEL_LAP

0
1
IIN-1 (L)

VIN = 0 V, PWM, OC, WAVE_U,
SEL_LAP
−75
−50

IIN-2 (H)

VIN = 5 V, CW_CCW, LA0, LA1

50
75
IIN-2 (L)

VIN = 0 V, CW_CCW, LA0, LA1
−1
0

VIN (H)

3.5

5
Input voltage
Input hysteresis voltage
VIN (L)

VH

VO-1 (H)

VO-1 (L)

VO-2 (H)

Output voltage
VO-2 (L)

VO-3 (H)

VO-3 (L)

Test Condition
PWM, OC, SEL_LAP, CW_CCW
WAVE_U, LA0, LA1
PWM, OC, SEL_LAP, CW_CCW
V
GND

1.5

0.6

4.3

VDD
GND

0.5
4.0

VDD
WAVE_U, LA0, LA1
PWM, OC, SEL_LAP, CW_CCW
WAVE_U, LA0, LA1
IOH = −1 mA
OUT_UP, OUT_VP, OUT_WP
IOL = 20 mA
OUT_UP, OUT_VP, OUT_WP
IOH = −20 mA
OUT_UN, OUT_VN, OUT_WN
IOL = 1 mA
GND

0.5
4.0

VDD
GND

0.5

0
10
FG_OUT
IOL = 0.5 mA
V
V
OUT_UN, OUT_VN, OUT_WN
IOH = −0.5 mA
µA
FG_OUT
VDD = 5.5 V, VOUT = 0 V
IL (H)

OUT_UP, OUT_VP, OUT_WP
OUT_UN, OUT_VN, OUT_WN
FG_OUT
Output leak current
µA
VDD = 5.5 V, VOUT = 5.5 V
IL (L)

OUT_UP, OUT_VP, OUT_WP
OUT_UN, OUT_VN, OUT_WN

0
10

0.5
1

0.5
1
FG_OUT
Output delay time
tpLH
tpHL

PWM-Output
10
µs
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TB6548F
Application Circuit Example
VDD = 5 V
VM = 20 V
VDD
Positional detection signal
WAVE
COMP
OUT_UP
IN_UP
OUT_UN
IN_UN
OUT_VP
IN_VP
OUT_VN
IN_VN
OUT_WP
IN_WP
OUT_WN
IN_WN
PWM signal
PWM
OUT_U
OUT_V
OUT_W
M
FG signal
FG_OUT
RF
VISD1
<TB6548F>
VISD2
GND
1Ω
GND
ISD
Over current detection
signal
0.01 µF
OC
<TA84005F>
Note 1: Take enough care in designing output VDD line and GND line to avoid short circuit between outputs, VDD
fault or GND fault which may cause the IC to break down.
Note 2: The above application circuit and values mentioned are just an example for reference. Since the values may
vary depending on the motor to be used, appropriate values must be determined through experiments before
using the device.
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TB6548F
Package Dimensions
Weight: 0.32 g (typ.)
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TB6548F
RESTRICTIONS ON PRODUCT USE
000707EBA
• TOSHIBA is continually working to improve the quality and reliability of its products. Nevertheless, semiconductor
devices in general can malfunction or fail due to their inherent electrical sensitivity and vulnerability to physical
stress. It is the responsibility of the buyer, when utilizing TOSHIBA products, to comply with the standards of
safety in making a safe design for the entire system, and to avoid situations in which a malfunction or failure of
such TOSHIBA products could cause loss of human life, bodily injury or damage to property.
In developing your designs, please ensure that TOSHIBA products are used within specified operating ranges as
set forth in the most recent TOSHIBA products specifications. Also, please keep in mind the precautions and
conditions set forth in the “Handling Guide for Semiconductor Devices,” or “TOSHIBA Semiconductor Reliability
Handbook” etc..
• The TOSHIBA products listed in this document are intended for usage in general electronics applications
(computer, personal equipment, office equipment, measuring equipment, industrial robotics, domestic appliances,
etc.). These TOSHIBA products are neither intended nor warranted for usage in equipment that requires
extraordinarily high quality and/or reliability or a malfunction or failure of which may cause loss of human life or
bodily injury (“Unintended Usage”). Unintended Usage include atomic energy control instruments, airplane or
spaceship instruments, transportation instruments, traffic signal instruments, combustion control instruments,
medical instruments, all types of safety devices, etc.. Unintended Usage of TOSHIBA products listed in this
document shall be made at the customer’s own risk.
• The products described in this document are subject to the foreign exchange and foreign trade laws.
• The information contained herein is presented only as a guide for the applications of our products. No
responsibility is assumed by TOSHIBA CORPORATION for any infringements of intellectual property or other
rights of the third parties which may result from its use. No license is granted by implication or otherwise under
any intellectual property or other rights of TOSHIBA CORPORATION or others.
• The information contained herein is subject to change without notice.
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