5-phase Stepper Motor Star Connection Unipolar Driver IC SI-7500A ■ Ratings (Ta = 25°C) Absolute maximum rating Supply voltage Output current (A) (V) Junction temperature (°C) Operating ambient temperature (°C) Storage temperature (°C) Type No. VCC Vb Io Tj Top Tstg SI-7500A 40 8 1.2 +125 –20 to +80 –30 to +100 ■ Characteristics Electrical characteristics Operating supply voltage Type No. Vb input External *Input voltage *Input current zener diode current breakdown voltage (V) (mA/ø) (%) (mA) (V) (V) (mA) VCC Vb IO I OPD/IO Ib VZ V IH1 V IH2 VIL IIH1 I IH2 min typ max min typ max min typ max min typ max max min max max max max max max SI-7500A 17 24 30 4.5 5 Output current Power down Ratio 5.5 200 750 1000 35 50 100 VCC x1.5 15 50 3.9 1.3 0.6 0.21 0.22 Zener diode for canceling counter EMF Auxiliary power supply Vb ZD Variable current resistor Reference voltage Rx Comparator amplifier M Current controller Trigger pulse generator circuit Excitation signal amplifier Excitation signal 2-3 phase excitation Trigger pulse time (V) Vtrig min max (µs) Ttrig min typ (kHz) Ftrig typ max 4.0 1.0 20 Vb 2.0 25 * Input voltage and input current conditions VIH1 : Vb = 5V, Q1 to Q5ON RX = , I IN = 0.2mA VIH2 : Vb = 5V, Q1 to Q5OFF, IIN = 0.22mA IIH1 : Vb = 5V, Q1 to Q5ON, VIN = 3.7V IIH2 : Vb = 5V, Q1 to Q5OFF, VIN = 0.9V ■ Block diagram Main power supply VCC (Ta = 25°C) Trigger pulse frequency Trigger pulse voltage Counter EMF Canceller SI-7500A Current detection resistor Rs ■ Equivalent circuit diagram w ri t o !2 !5 !3 !6 !9 q @0 Q6 Q7 R36 R1 R6 D1 Q11 D11 D6 u R7 R41 Q1 R47 R2 D12 D13 D7 D8 R3 R16 R17 R32 R39 R8 R43 R44 Q2 Q3 R28 D14 D15 R18 R19 R10 D5 Q15 D9 D10 R15 Q4 R40 R5 R14 R23 R27 Q10 R9 R4 Q14 D4 R13 R22 R31 Q9 R38 D3 Q13 R12 R21 R26 Q8 Q12 D2 R42 MIC1 R11 R46 R37 R45 MIC3 Q5 R20 R24 R34 R25 R29 R30 R35 !8 e y !0 !1 !4 !7 43 SI-7500A ■ Diagram of external circuits SI-7500A 5-phase stepper motor VCC + 100 µ F 50V ZD 9 13 16 OUT-5 OUT-4 5 OUT-3 Vb 2 OUT-2 VCC VR 44kΩ ZD 7 Vb 20 OUT-1 1 IN-2 1kΩ 4 8 7 2 1S1555 IN-3 IN-4 Vief. IN-5 4 8 Excitation signal input (Active High) 2-3 phase excitation 12 15 19 RS5 RS4 RS3 11 RS2 RX 0.01µF RS1 1kΩ 18 GND 1000pF 3 1 6 5 SI-7500A 2SA561 3.9kΩ 555 VR 300Ω IN-1 3 6 10 14 17 RS1 RS2 RS3 RS4 RS5 RS1 to RS5 : Current detection resistor RX : Variable current resistor Power down signal input (Active high) ■ External dimensions (Unit: mm) ■ Supply voltage vs. Output current Plastic package 3.5 3.8 8.0 φ 8.6±1 3.4 1.8 35.0±0.5 Type No. Lot No. 3 0.5 P=2.54 Pin No. Rx = ∞ 1.2 Output current Io (A) 7.0±0.5 63.0±0.4 16.6 69.0±0.5 (Typical value, Motor : PH566-B Rs = 1Ω Vb = 5.0V 2kΩ 1.0 1kΩ 0.8 510Ω 0.6 200Ω 100Ω 0.4 0.2 1.4 12....................................20 0 0 20 24 30 Supply voltage VCC (V) ■ Case temperature vs. Output current ■ Torque characteristics 1.0 0.8 0.6 0.4 0.2 0 0 25 50 75 Case temperature Tc (°C) 44 2.5 Pull-out torque τOUT (kg-cm) Output current Io (A) (Typical value) VCC=24V Motor : PH566-B 100 2.0 1.5 Supply voltage VCC = 24V Vb = 5V Output current Io = 0.8 A/phase (fixed) Counter EMF canceler Zener diode Vz = 49V Motor : PH566B 1.0 0.5 0 0 0.1 0.2 0.5 1 2 Response frequency f (kpps) 5 10 20 SI-7500A Application Note ■ Determining the output current IO (motor coil current) The main elements that determine the output current are Current detection resistor Rs, Supply voltage Vb, and Variable current resistor RX. Fig. A IOH (1) Normal mode To operate a motor at maximum current level, set RX to infinity (open). From Fig. A, when the maximum output current ripple is designated as IOH, its value will be, VRSH IOH = ....................................................... [A] RS Waveform of output current Fig. B 1.4 V RSH can be computed as follows: V) VRSH Max. (Vb = 5.0 1.2 VRSH = 0.2 Vb + 0.213 (center value) .............. [B] The relationship between I OH and RS is shown in Fig. B. VRSH (V) From equations [A] and [B], the output current I OH can be computed as follows: I (0.2 Vb + 0.213) IOH = RS 1.0 VRSH Min. (Vb = 5.0V) 0.8 Vb + 0.1 VRSH(max) = 4.69 + 1.92 + 0.2 (V) Rx Vb + 0.09 VRSH(min) = 5.25 + 2.06 + 0.15 (V) Rx 0.6 0.4 (Rx : kΩ) 0.2 (2) Power down mode When an external resistor RX is connected, VRSH changes as shown in the Fig. B even when RS is retained. Obtain the power down output current I OHPD from Fig. B and equation [A]. 0 0 1 2 3 4 ∞ External resistor Rx (kΩ) ■ Thermal design Obtain the internal power dissipation that corresponds to the output current to be required from Fig. C, multiply this by three, and determine the size of the heatsink from the derating curve in Fig. D. The derating curve is based on junction temperature of 125°C. However, make some allowance so that Tc is 85°C or less and then select the proper heatsink size. Fig. C SI-7500A Internal power dissipation per phase PD vs. Output current IO Fig. D SI-7500A Derating curve 6 Motor : PH566-B Vb = 5V Holding mode 150 × 100 Heatsink : Aluminum Thickness : 2 mm 100 × 100 5 Power dissipation PD (W) Power dissipation per phase Pdiss/φ (W) 20 (Typical value) 4 3 VCC = 30V 24V 20V 2 15 50 × 100 10 Without heatsink 5 1 0 0 0.2 0.4 0.6 0.8 Output current lo (A) 1.0 1.2 0 0 20 40 60 80 Ambient temperature Ta (°C) 45 SI-7200M, SI-7230M, SI-7115B, SI-7300A, SI-7330A, SI-7500A and SI-7502 Handling Precautions (Note: The SI-7502 is applicable for item (2) only.) For details, refer to the relevant product specifications. (1) Tightening torque: The torque to be applied in tightening screws when mounting the IC on a heatsink should be below 49N•m. (2) Solvent: Do not use the following solvents: Substances that Chlorine-based solvents : Trichloroethylene, dissolve the package Trichloroethane, etc. Aromatic hydrogen compounds : Benzene, Toluene, Xylene, etc. Ketone and Acetone group solvents Substances that weaken the package Gasoline, Benzine and Kerosene (3) Silicone grease: The silicone grease to be used between the aluminum base plate of the hybrid IC and the heatsink should be any of the following: • G-746 SHINETSU CHEMICAL INDUSTRIES CO., LTD. • YG6260 TOSHIBA SILICONE CO., LTD. • SC102 DOW CORNING TORAY SILICONE CO., LTD. Please pay sufficient attention in selecting silicone grease since oil in some grease may penetrate the product, which will result in an extremely short product life. Others • Resistance against radiation Resistance against radiation was not considered in the development of these ICs because it is assumed that they will be used in ordinary environment. 54