Description
The CXA3071N is a monolithic IC designed for use with three-mode Floppy Disk Drives, and contains a read circuit (with a four-mode filter system), a write circuit, an erase circuit, and a supply voltage detection circuit, all on a single chip.

Features
• Single 5V power supply
• All filter, write current and other characteristics can be set with a single external resistor.
• Filter system can be switched among four modes: 1M, 1.6M/2M, which are each inner track/outer track.
• Filter characteristics can be set to Chebyshev (1dB ripple) for 1.6M, 2M/inner track only, and to Butterworth for the other modes and a custom selection can be made between Chebyshev (1dB ripple) and Butterworth for 1.6M, 2M/inner track only.
• 1M/outer track f0 and the fc ratio for each mode can be customized.
• Preamplifier voltage gain can be set to 45dB or 48dB by switching the filter mode and inner/outer track.
• Preamplifier and filter output are monitored with the same pins. These pins are normally set to filter output, but the preamplifier output can be monitored by temporarily setting the SETR pin (Pin 20) to Low.
• Time domain filter can be switched between two modes: 1M, 1.6M/2M. In addition, the pulse width can be customized.
• Write current can be switched among six modes according to the mode and inner/outer track setting. The current value can be customized for each mode.
• Erase current remains constant, and the current value can be customized.
• Damping resistor can be built in. Resistor can be customized between 2kΩ and 15kΩ in 1kΩ steps.
• Supply voltage detection circuit

Applications
    Three-mode FDDs