ROHM BA6492BFS Datasheet

Motor driver ICs

FDD spindle motor driver

BA6492BFS

The BA6492BFS is a one-chip IC designed for driving 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, two monostable multivi­brator elements, and a power save circuit. The compactly packaged IC reduces the number of external components
required.

Applications
Floppy disk drivers

Features

1) 3-phase, full-wave soft switching drive system.

2) Digital servo circuit.

3) Power save circuit.

Absolute maximum ratings (Ta = 25C)

4) Hall power supply switch.

5) Motor speed changeable.

6) Index amplifier. Built-in 2 monostable multivibrator.

Recommended operating conditions (Ta = 25C)

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Motor driver ICs BA6492BFS

Block diagram

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Motor driver ICs BA6492BFS

Pin descriptions

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Motor driver ICs BA6492BFS

Input/output circuits
(1) Monostable multivibrator element timing setting

(3, 4 pin)

(3) Speed discriminator output (6 pin) (4) Integrating amplifier (7, 8 pin)

(2) Constant voltage output (5 pin)

(5) Motor output (1115 pin) (6) Hall bias (16 pin)

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