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.) 1 2001-08-28 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 2 2001-08-28 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 3 2001-08-28 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%. 4 2001-08-28 TB6548F 4. PWM Control Upper turn-on signal (OUT-P) Lower turn-on signal (OUT-N) Output voltage of TA84005F 5 2001-08-28 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 6 2001-08-28 TB6548F 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 7 2001-08-28 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. 8 2001-08-28 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 9 2001-08-28 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 2001-08-28 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. 11 2001-08-28 TB6548F Package Dimensions Weight: 0.32 g (typ.) 12 2001-08-28 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. 13 2001-08-28