XR-3470B

XR-3470A/3470B Floppy Disk Read Amplifier GENERAL DESCRIPTION The XR-3470Al3470B is read amplifier system designed primarily for use in a floppy disk drive system. It is designed to perform the complete readback function, by accepting the readback signal from a magnetic head and converting it into digital output pulses. To perform this function, the circuit contains a high-frequency amplifier, an active differentiator, a zero-crossing detector, and a time domain filter. The XR-3470Al3470B is suited for systems with data transfer rates up to 3 megabaud. High input sensitivity allows operation with signal levels as low as 1.4 mV pp, which gives it the flexibility to be used for single or double density floppy disk systems. The XR-3470Al3470B offers improvements (over the standard 3470) of lower peak shift and power part-topart input amplifier gain variations. The XR-3470Al3470B, available in an 18 Pin DIP, is powered by + 5 and + 12 volt power supplies. FUNCTIONAL BLOCK DIAGRAM r AMPL...