BH6627FS

Magnetic disk ICs Read / Write amplifier for FDD BH6627FS The BH6627FS is a 4-mode read / zwrite IC designed for floppy disk drives. This IC has an internal active filter that can be set to any of multiple settings according to transfer rate, and internal switches for density and inner track / outer track. Write current can be set to any of multiple settings. FApplications Floppy disk drives (1MB, 1.6MB and 2MB drives) FFeatures 1) Internal active filter with four settings that can be selected for multiple Q and f0. 2) Time domain filter with internal switch set according to transfer rate. 3) Any of multiple write current settings can be selected, and inner track/outer track switching is done internally. FAbsolute maximum ratings (Ta = 25_C) FRecommended operating conditions 535 Magnetic disk ICs FBlock diagram BH6627FS 536 Magnetic disk ICs FPin descriptions BH6627FS 537 Magnetic disk ICs BH6627FS 538 Magnetic disk ICs BH6627FS 539 Magnetic disk ICs BH6627FS 540 Magnetic disk ICs FElectrical characteristics (unless otherwise noted, Ta = 25_C, VCC = 5V) BH6627FS 541 Magnetic disk ICs BH6627FS 542 Magnetic disk ICs BH6627FS 543 Magnetic disk ICs FRead characteristics BH6627FS Total filter peak frequency setting f0 = a / (RRCC [kΩ] +0.09) [kHz] FILC “H” a = 313 330 376 387 675 844 765 748 “L” 313 330 376 387 627 765 706 754 250 [kbps] outer track 250 [kbps] inner track 300 [kbps] outer track 300 [kbps] inner track 500 [kbps] outer track (when ...