May 1994 Order Number: 290166-007
82077AA
CHMOS SINGLE-CHIP FLOPPY DISK CONTROLLER
Y
Single-Chip Floppy Disk Solution
Ð 100% PC AT* Compatible
Ð 100% PS/2* Compatible
Ð 100% PS/2 Model 30 Compatible
Ð Integrated Drive and Data Bus
Buffers
Y
Integrated Analog Data Separator
Ð 250 Kbits/sec
Ð 300 Kbits/sec
Ð 500 Kbits/sec
Ð 1 Mbits/sec
Y
High Speed Processor Interface
Y
Perpendicular Recording Support
Y
Integrated Tape Drive Support
Y
12 mA Host Interface Drivers, 40 mA
Disk Drivers
Y
Four Fully Decoded Drive Select and
Motor Signals
Y
Programmable Write Precompensation
Delays
Y
Addresses 256 Tracks Directly,
Supports Unlimited Tracks
Y
16 Byte FIFO
Y
68-Pin PLCC
(See Packaging Spec., Order
Ý
240800, Package Type N)
The 82077AA floppy disk controller has completely integrated all of the logic required for floppy disk control.
The 82077AA, a 24 MHz crystal, a resistor package and a device chip select implements a PC AT or PS/2
solution. All programmable options default to compatible values. The dual PLL data separator has better
performance than most board level/discrete PLL implementations. The FIFO allows better system perform-
ance in multi-master systems (e.g. PS/2, EISA). The 82077AA is available in three versionsÐ82077AA-5,
82077AA and 82077AA-1. 82077AA-1 has all features listed in this data sheet. It supports both tape drives and
4 Mb floppy drives. The 82077AA supports 4 Mb floppy drives and is capable of operation at all data rates
through 1 Mbps. The 82077AA-5 supports 500/300/250 Kbps data rates for high and low density floppy
drives.
The 82077AA is fabricated with Intel’s CHMOS III technology and is available in a 68-lead PLCC (plastic)
package.
290166–1
Figure 1. 82077AA Pinout
*PS/2 and PC AT are trademarks of IBM.
