Motor driver ICs 3-phase motor driver for CD-ROMs BD6660FV The BD6660FV is low power consumption CD-ROM spindle driver that uses MOS transistor in the output. To meet the requirements for notebook computers, the thin power package SSOP-B28 is used and a PWM drive with a MOS processor output stage achieves an extremely low power consumption. Applications Portable CD-ROMs, DVDs Features 1) Direct PWM drive. 2) Built-in power save circuit. 3) Built-in current limiter circuit. 4) Built-in FG output. 5) Built-in Hall biasing. 6) 7) 8) 9) 10) Built-in reverse-rotation prevention circuit. Built-in short brake. Low power consumption with the output MOSFET. Built-in brake mode switching circuit. Built-in rotation detection pin. Absolute maximum ratings (Ta = 25C) Recommended operating conditions (Ta = 25C) 769 Motor driver ICs Block diagram 770 BD6660FV Motor driver ICs BD6660FV Pin descriptions Input and output circuits (1) Power save 771 Motor driver ICs (2) Torque amplifier (3) MODE1 (5) Output pin 772 BD6660FV (4) MODE2 Motor driver ICs (6) Hall bias pin (7) FG output / CP1 output / FR output BD6660FV (8) CP2 / VPUMP output 773 Motor driver ICs Electrical characteristics (unless otherwise noted, Ta = 25C, VCC = 5V, VM = 5V) 774 BD6660FV Motor driver ICs BD6660FV 775 Motor driver ICs Application example 776 BD6660FV Motor driver ICs Operation notes (1) Brake mode (MODE1) logic The brake mode is switched by MODE1 pin and the operation is shown in Table-1 below. BD6660FV (3) PWM operation By the voltage potential difference between EC and ECR, the ON duty when switching the low level output transistor changes as shown in Fig. 11 below. (ECR = 1.65V) (2) MODE2 logic The FG output is switched by MODE2 pin and the operation is shown in Table-2 below. (4) Current limiter operation When the RNF voltage becomes 0.2V (Typ.), the current limiter circuit activates and limits the PWM ON duty. At this time the output current Iomax is limited to: Iomax approx. 0.2 / RNF 777 Motor driver ICs (5) OSC oscillator circuit By connecting a capacitor to the OSC pin, the charging and discharging of the capacitor generates a triangular wave as that shown in Fig. 12. (C = 470pF and f = 100kHz (Typ.)) (6) Charge pump The boost voltage (VPUMP) is VM VCC. Therefore, to prevent (VM VCC) from increasing much over ratings, set the VM and VCC voltages. 778 BD6660FV Motor driver ICs (7) BD6660FV Timing chart 779 Motor driver ICs External dimensions (Units: mm) 780 BD6660FV