BA6486FS Rohm, BA6486FS Datasheet

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... FDD spindle motor driver BA6486FS The BA6486FS is a one-chip IC designed for driving 12V FDD spindle motors. This high-performance IC employs a 3-phase, full-wave soft switching drive system, and contains a digital servo, an index amplifier, and a power save circuit. The compactly packaged IC reduces the number of external components required. ...

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... Motor driver ICs FBlock diagram BA6486FS 545 ...

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... Motor driver ICs FPin descriptions FElectrical characteristics (unless otherwise noted 25_C, V 546 BA6486FS = 12V) CC ...

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... The frequency divider reduces the fre- quency of the OSC signal. The FG amplifier amplifies the minute voltage generated by the motor FG pattern and produces a rectangular-shaped speed signal. The FG amplifier gain (G internal resistance ratio. BA6486FS voltage, NF pin exceeds the current lim the constant voltage V ...

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... Hall device current is shut down. S Thermal shutdown circuit This circuit shuts down the IC currents when the chip junction temperature is increased to about 175_C (typi- cal). The thermal shutdown circuit is deactivated when the temperature drops to about 155_C (typical). BA6486FS ...

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... Motor driver ICs BA6486FS 549 ...

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... Motor driver ICs 550 BA6486FS ...

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... Design a proper conductor pattern in consideration of the motor current that flows through pin 14. (5) External clock Make sure that the pin 7 voltage is always less than V and more than the ground voltage. p-p (4) External clock input (7 pin) BA6486FS CC 551 ...

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... Motor driver ICs (5) Motor output (11X15 pin) (7) Hall input (17X22 pin) (9) Speed discriminator output (30 pin) 552 (6) Hall bias (16 pin) (8) Integrating amplifier (28, 29 pin) (10) Start / stop (31 pin) (11) Index output (32 pin) BA6486FS ...

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... Motor driver ICs FApplication example BA6486FS 553 ...

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... Motor driver ICs FElectrical characteristic curves FExternal dimensions (Units: mm) 554 BA6486FS ...