Overview
The LA6503 was developed for CAV control CD-ROM drives, and provides spindle motor driver, sled motor driver, and sled motion/position detection circuits.
Functions and Features
• CAV control spindle motor driver
— Three-phase brushless motor driver
— IOmax = 1 A
— Built-in FG output circuit (single Hall detection output)
— Reverse braking circuit
— Built-in start/stop circuit
— Upper side current detection for minimal loss in the current detection resistor. Also, the voltage drop in this resistor reduces the IC internal power dissipation.
— Built-in thermal shutdown circuit
• Sled motor driver
— One built-in BTL driver channel
— IOmax = 1 A
— Wide dynamic range
— Built-in level shifting circuit
— Muting (output on/off) circuit
— Built-in thermal shutdown circuit
• Sled motion/position detection circuit
— Circuit that provides a pulse output corresponding to sled motion and position
— This circuit emits 96 pulses for each rotation from a 24-pole magnet and 90° phase difference Hall element motors, and thus detects the distance moved. It also provides two 48-pulse outputs with differing phases such that the motion direction can be detected from the phase difference between those signals.
• Hall bias power supply
— Generates the Hall element 3-V bias voltage.
— IOmax = 30 mA, typical