DESCRIPTION

The F-VHS Motor Driver COMBO IC includes a double three phase brushless motor driver plus a DC full bridge motor driver for VCR application. The package is SDIP42 (38+2+2 pin ground frame).

The device is realized in BCD technology with power LDMOS output stages.

The gate drive for high side stages is provided by an internal charge pump with two external capacitors. The first three phase motor driver is devoted to the DRUM motor control.

The phase sequence update signal is provided initially by an external start-up signal (FSTART), whose frequency is internally divided by four, while, during normal operation, is provided by an optical tacho converter signal.

This signal is used as clock and reset for the state machine.

The second three phase motor driver is devoted to the CAPSTAN control. While the DRUM will always spin in a fixed direction, the CAPSTAN motor needs a more sophisticated logic to control the changes in spin direction.

The motor position detection is carried out by means of three comparators for Hall effect sensors. The loop regulation for this motor is still provided by the μP with the signals CPWM and CDIR.