Document
TOSHIBA CMOS Integrated Circuit Silicon Monolithic
TB6575FNG
PWM Sensorless Controller for 3-Phase Full-Wave BLDC Motors
TB6575FNG
The TB6575FNG provides sensorless commutation and PWM current control for 3-phase full-wave BLDC motors. It controls rotation speed by changing a PWM duty cycle by analog voltage.
Features
• 3-phase full-wave sensorless drive
• PWM chopper drive
• PWM duty cycle control by analog input
• 20-mA current sink capability on PWM output pins • Overcurrent protection
Weight: 0.14 g (typ.)
• Forward/reverse rotation
• Lead angle control (7.5° and 15°)
• Overlap commutation
• Rotation speed sensing signal
• DC excitation mode to improve startup characteristic
• DC excitation time and forced commutation time for startup operation can be changed.
• Forced commutation frequency can be selected. (fXT/(6 × 216), fXT/(6 × 217), fXT/(6 × 218) )
• Output polarity switching (P-channel + N-channel, N-channel + N-channel)
TB6575FNG is a Pb-free product. The following conditions apply to solderability: *Solderability 1. Use of Sn-37Pb solder bath
*solder bath temperature = 230ºC *dipping time = 5 seconds *number of times = once *use of R-type flux 2. Use of Sn-3.0Ag-0.5Cu solder bath *solder bath temperature = 245ºC *dipping time = 5 seconds *number of times = once *use of R-type flux
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2008-9-11
Block Diagram
Duty 19
VSP 5
Startup time setting
6-bit AD converter
PWM control
SC 2 START 8
IP 9 FST 24
FMAX 4
LA 12 CW_CCW 6
DC excitation control circuit
Forced commutation frequency setting
Maximum commutation frequency setting
Lead angle setting
SEL_LAP 20
Clock generation
10
11
XTout
XTin
Pin Assignment
TB6575FNG
VDD
OS FG_OUT
21
3
7
PWM generator
Timing control
13 OUT_UP 15 OUT_VP 17 OUT_WP 14 OUT_UN 16 OUT_VN 18 OUT_WN
Overcurrent protection
22 OC
1 GND
Position recognition
23 WAVE
GND 1 SC 2 OS 3
FMAX 4 VSP 5
CW_CCW 6 FG_OUT 7 START 8 IP 9 XTout 10 XTin 11 LA 12
24 FST 23 WAVE 22 OC 21 VDD 20 SEL_LAP 19 Duty 18 OUT_WN 17 OUT_WP 16 OUT_VN 15 OUT_VP 14 OUT_UN 13 OUT_UP
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2008-9-11
Pin Description
Pin No. 1 2
Symbol GND SC
3
OS
4
FMAX
5
VSP
6
CW_CCW
7
FG_OUT
8
START
9
IP
10
XTout
11
XTin
12
LA
13
OUT_UP
14
OUT_UN
15
OUT_VP
16
OUT_VN
17
OUT_WP
18
OUT_WN
19
Duty
20
SEL_LAP
TB6575FNG
I/O
Description
⎯ Ground pin
I
Connection pin for a capacitor to set a startup commutation time and duty cycle ramp-up time
Select the polarity of transistors.
High or open: High-side transistor = P-channel (active low)
I
Low:
Low-side transistor = N-channel (active High) High-side transistor = N-channel (active High)
Low-side transistor = N-channel (active High)
The pin has a pull-up resistor.
Set an upper limit of the maximum commutation frequency.
FMAX =High or Open , Maximum commutation frequency fMX = fXT/ (6×211)
I
FMAX =Low , Maximum commutation frequency fMX = fXT/(6 × 212)
FMAX =High or Open , Maximum commutation frequency fMX = fXT/ (6×28) FMAX =Low , Maximum commutation frequency fMX = fXT/(6 × 29) The pin has a pull-up resistor.
Duty cycle control input
0 ≤ VSP ≤ VAD (L): Output off
I
VAD (L) ≤ VSP ≤ VAD (H): Set the PWM duty cycle according to the analog input.
VAD (H) ≤ VSP ≤ VDD: Duty cycle = 100% (31/32)
The pin has a pull-down resistor.
Rotation direction input
I
High:
Reverse rotation (U → W → V)
Low or open: Forward rotation (U → V → W)
The pin has a pull-down resistor.
Rotation speed sensing output
O
The pin is low at startup or upon a detection of a fault. This pin drives three pulses per rotation (3 ppr) based on the back-EMF (electromotive force) sensing. (In the case of 4
pole motor, 6 pulse output per rotation.)
O DC excitation time setting pins
When VSP ≥ 1 V (typ.), the START pin goes low to start DC excitation.
I
After the IP pin reaches VDD/2, the TB6575FNG moves from DC excitation to forced
commutation mode.
⎯ Connection pins for a ceramic oscillator ⎯ These pins have a feedback resistor.
Lead angle control input
I
LA = Low or open: Lead angle of 7.5°
LA = high:
Lead angle of 15°
The pin has a pull-down resistor.
O
PWM output signal for the high-side (positive-side) transistor driving motor phase U The PWM polarity can be specified by pin 3.
O
PWM output signal for the low-side (negative-side) transistor driving motor phase U This signal is active high.
O
PWM output signal for the high-side (positive-side) transistor driving motor phase V The PWM polarity can be specified by pin 3.
O
PWM output signal for the low-side (negative-side) transistor driving motor phase V This signal is active high.
O
PWM output signal for the high-side (positive-side) transistor driving motor phase W The PWM polarity can be specified by pin 3.
O
PWM output signal for the low-side (negative-side) transistor driving motor phase W This signal is active high.
PWM output monito.