LX5241/5242/5243

PRODUCT D A T ABOOK 1996/1997

5

Copyright © 2000

Rev. 1.4 11/00

UltraMAX

1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-6Negative signal termination lines for LVD mode. Signal termination lines for SE mode.

1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+, 9+ Positive signal termination lines for LVD mode. Pseudo-ground lines for SE mode.

V

TERM

Power supply pin for terminator. Connect to SCSI bus TERMPWR. Must be decoupled by one 4.7µF

low-ESR capacitor for every three terminator devices. It is absolutely necessary to connect this pin to

the decoupling capacitor through a very low impedance (big traces on PCB). Keeping distances very

short from the decoupling capacitors to the V

capacitor is somewhat layout dependant and some applications may benefit from high-frequency

decoupling with 0.1µF capacitors right at V

DISCONNECT6Enables / disables terminator. See Power Down Function Table for logic levels per device.

GND6Terminator ground pin. Connect to ground.

MASTER / SLAVE6Sometimes referred to as M/S pin in this data sheet. Used to select which terminator is the control-

ling device. MASTER/SLAVE pin High or Open enables the DIFFSENSE output drive. Please see

MASTER/SLAVE Function Table.

DIFFSENSE6This is a dual function pin. It drives the SCSI bus DIFFSENS line. It is also the sense pin to detect the

SCSI bus mode (LVD, SE or HVD). DIFFSENSE output drive can be disabled with Low level on the

MASTER/SLAVE pin. Please see DIFFSENSE and MASTER/SLAVE Function Tables. Internally

connected to DIFFB pin through 20kOhm resistor.

DIFFB6Internally connected to DIFFSENSE pin through 20kOhm resistor. It can be used as a mode sense

pin when the device is a non-controlling terminator (MASTER/SLAVE pin is Low). An RC filter

(20kOhm / 0.1µF) is not required on the LX5241/42/43, as it has an internal timer.

SE6Single-ended output; when High, terminator is operating in SE mode.

LVD6Low Voltage Differential output. When High, terminator is operating in LVD mode.

HVD6High Voltage Differential output. When High, terminator is operating in HVD mode.

HEATSINK6Attached to die mounting pad, but not bonded to GND pin. Pins should be considered a heat sink

only, and not a true ground connection. It is recommeneded that these pins be connected to ground,

but can be left floating.

Pin

Designator

Description

FUNCTIONAL PIN DESCRIPTION