TB6548F/FG TOSHIBA CMOS Integrated Circuit Silicon Monolithic TB6548F/FG Three-Phase Full-Wave PWM Sensorless Controller for Brushless DC Motors The TB6548F/FG is a three-phase full-wave sensorless controller for brushless DC motors. The device supports voltage control by PWM signal input and is capable of PWM type sensorless driving when used in conjunction with the TA84005F/FG. Features • Three-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.) TB6548FG: The TB6548FG 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 1 2006-03-02 TB6548F/FG Block Diagram VDD FG_OUT 13 6 14 OUT_UP PWM 3 PWM Control 17 OUT_VP SEL_LAP 8 CW_CCW 4 Turn-on Signal Forming Circuit Rotation Instruction 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 2006-03-02 TB6548F/FG Pin Description Pin No. Symbol I/O Description Lead angle setting signal input pin 1 2 LA0 LA1 I I • LA0 = Low, LA1 = Low: Lead angle of 0 degrees • LA0 = High, LA1 = Low: Lead angle of 7.5 degrees • LA0 = Low, LA1 = High: Lead angle of 15 degrees • LA0 = High, LA1 = High: Lead angle of 30 degrees • 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. Rotational 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 Rotational frequency detection signal output pin • Equivalent to U-phase signal (except PWM) Not connected Lap turn-on select pin • Low: Lap turn-on • High: 120 degrees turn-on • Built-in pull-up resistor 8 SEL_LAP I 9 NC ⎯ Not connected 10 XT ⎯ Resonator connecting pin 11 XTin ⎯ 12 GND ⎯ 13 VDD ⎯ • Selects starting commutation frequency. 17 Starting commutation frequency fst = Resonator frequency fxt/(6 × 2 ) Connected to GND. Connected to 5 V power supply. 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 ⎯ • V-phase winding wire positive ON/OFF switching pin • ON: Low, OFF: High Not connected V-phase lower turn-on signal output pin 19 20 OUT_VN NC O ⎯ • V-phase winding wire negative ON/OFF switching pin • ON: High, OFF: Low Not connected 3 2006-03-02 TB6548F/FG 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 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 the start instruction by PWM signal, the turn-in signal for forcible commutation (commutation irrespective of the rotor position of the motor) is output and the motor starts to rotate. The rotation of the motor causes induced voltage on the wirewound pin for each phase. When signals indicating positive or negative for pin voltage (including induced voltage) for each phase are input through their respective positional signal input pins, the turn-on signal for forcible commutation is automatically switched to the turn-on signal for the positional signal (induced voltage). Thereafter, the 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 bits (within the IC). + Starting commutation frequency fst = Resonator frequency fxt/(6 × 2 (bit 3)) bits = 14 The forcible commutation frequency at the time of start can be adjusted using the inertia of the motor and the 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 The PWM signal can be reflected in the turn-on signal by supplying the PWM signal from external sources. The frequency of the PWM signal should be set adequately high with regard to the electrical frequency of the motor and in accordance with the switching characteristics of the drive circuit. Because positional detection is performed in synchronization with the falling edges of the PWM signal, positional detection cannot be performed with 0% duty or 100% duty. Duty (max) 250 ns Duty (min) 250 ns Even if the duty is 99%, the duty of the voltage applied to the motor is 100% owing to the storage time of the drive circuit. 4 2006-03-02 TB6548F/FG 4. PWM Control Upper turn-on signal (OUT-P) Lower turn-on signal (OUT-N) Output voltage of the TA84005F/FG 5 2006-03-02 TB6548F/FG 5. Positional Variation Since positional detection is performed in synchronization with the PWM signal, positional variation occurs in connection with the frequency of the PWM signal. Take particular care if using the IC for high-speed motors. Variation is calculated by detecting at two consecutive rising edges of the PWM signal. 1/fp < Detection time variation < 2/fp fp: PWM frequency PWM signal Output voltage of the TA84005F/FG Reference voltage Pin voltage Positional signal Ideal detection timing Actual detection timing 6 2006-03-02 TB6548F/FG 6. Lead Angle Control The lead angle is 0 degrees during the starting forcible commutation and, when normal commutation is started, automatically changes to the lead angle that 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 degrees 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 degrees PWM control 15 degrees OUT_UP OUT_UN OUT_VP OUT_VN PWM control OUT_WP OUT_WN PWM control (4) Lead angle: 30 degrees 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 electrical angle 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-degree 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 varies depending on the lead angle setting. Induced voltage Turn-on signal U V W (1) Lead angle: 0 degrees 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 degrees OUT_UP OUT_UN OUT_VP OUT_VN PWM control OUT_WP OUT_WN PWM control (4) Lead angle: 30 degrees OUT_UP OUT_UN PWM control OUT_VP OUT_VN OUT_WP OUT_WN PWM control PWM control 7 2006-03-02 TB6548F/FG 8. Start/Stop Control Start/Stop is controlled using the PWM signal input pin. A stop is acknowledged when the PWM signal duty is 0, and a start is acknowledged when the ON-signal of a frequency four times higher than the resonator frequency or greater is input continuously. Timing chart PWM signal Detection timing Start 512 periods at the resonator frequency First detection Second detection Start PWM signal Detection timing Stop 512 periods at the resonator frequency First detection Second detection and stop Note: Take sufficient care regarding noise on the PWM signal input pin. 8 2006-03-02 TB6548F/FG Absolute Maximum Ratings (Ta = 25°C) Characteristic Symbol Rating Unit VDD 5.5 V Vin −0.3 to VDD + 0.3 V Power supply voltage Input voltage Turn-on signal output current IOUT 20 mA 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) Characteristic Power supply voltage Input voltage PWM frequency Oscillation frequency Symbol Test Condition Min Typ. Max Unit VDD ⎯ 4.5 5.0 5.5 V Vin ⎯ −0.3 ⎯ VDD + 0.3 V fPWM ⎯ ⎯ 16 ⎯ kHz fosc ⎯ 1.0 ⎯ 10 MHz 9 2006-03-02 TB6548F/FG Electrical Characteristics (Ta = 25°C, VDD = 5 V) Characteristic Static power supply current Dynamic power supply current Input current Symbol Test Circui t Min Typ. Max Unit IDD ⎯ PWM = H, XTin = H ⎯ 0.1 0.3 mA IDD (opr) ⎯ 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 Test Condition VIN (L) ⎯ VH ⎯ VO-1 (H) ⎯ VO-1 (L) ⎯ VO-2 (H) ⎯ VO-2 (L) ⎯ VO-3 (H) ⎯ VO-3 (L) ⎯ Output voltage 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 GND ⎯ 0.5 4.0 ⎯ VDD GND ⎯ 0.5 ⎯ 0 10 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 µA V V OUT_UN, OUT_VN, OUT_WN IOH = −0.5 mA FG_OUT IOL = 0.5 mA 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 ⎯ 0 10 OUT_UN, OUT_VN, OUT_WN FG_OUT Output delay time tpLH ⎯ PWM-Output tpHL 10 ⎯ 0.5 1 ⎯ 0.5 1 µs 2006-03-02 TB6548F/FG 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/FG> VISD2 GND 1Ω GND ISD Overcurrent detection signal 0.01 µF OC <TA84005F/FG> Note 1: Utmost care is necessary in the design of the output, VCC, VM, and GND lines since the IC may be destroyed by short-circuiting between outputs, air contamination faults, or faults due to improper grounding, or by short-circuiting between contiguous pins. Note 2: The above application circuit and values mentioned are intended only as an example for reference. Since the values may vary depending on the motor to be used, appropriate values must be determined through experiment before use of the device. 11 2006-03-02 TB6548F/FG Package Dimensions Weight: 0.32 g (typ.) 12 2006-03-02 TB6548F/FG Notes on Contents 1. Block Diagrams Some of the functional blocks, circuits, or constants in the block diagram may be omitted or simplified for explanatory purposes. 2. Equivalent Circuits The equivalent circuit diagrams may be simplified or some parts of them may be omitted for explanatory purposes. 3. Timing Charts Timing charts may be simplified for explanatory purposes. 4. Application Circuits The application circuits shown in this document are provided for reference purposes only. Thorough evaluation is required, especially at the mass production design stage. Toshiba does not grant any license to any industrial property rights by providing these examples of application circuits. 5. Test Circuits Components in the test circuits are used only to obtain and confirm the device characteristics. These components and circuits are not guaranteed to prevent malfunction or failure from occurring in the application equipment. IC Usage Considerations Notes on handling of ICs [1] The absolute maximum ratings of a semiconductor device are a set of ratings that must not be exceeded, even for a moment. Do not exceed any of these ratings. Exceeding the rating(s) may cause the device breakdown, damage or deterioration, and may result injury by explosion or combustion. [2] Do not insert devices in the wrong orientation or incorrectly. Make sure that the positive and negative terminals of power supplies are connected properly. Otherwise, the current or power consumption may exceed the absolute maximum rating, and exceeding the rating(s) may cause the device breakdown, damage or deterioration, and may result injury by explosion or combustion. In addition, do not use any device that is applied the current with inserting in the wrong orientation or incorrectly even just one time. Points to remember on handling of ICs (1) Back-EMF When a motor rotates in the reverse direction, stops or slows down abruptly, a current flow back to the motor’s power supply due to the effect of back-EMF. If the current sink capability of the power supply is small, the device’s motor power supply and output pins might be exposed to conditions beyond maximum ratings. To avoid this problem, take the effect of back-EMF into consideration in system design. 13 2006-03-02 TB6548F/FG 14 2006-03-02