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LIN DOC #: 5122
UltraMAX
T
HE
TM
LX5122
AND
ULTRA 27-LINE, PLUG
I
NFINITE
PLAY SCSI TERMINATOR
D
ATA
P
OWER
OF
I
N N O VAT I O N
P
RODUCTION
S
HEET
DESCRIPTION The LX5122 Plug and Play UltraMAXTM terminator represents next-generation technology for SCSI termination applications. The low-voltage BiCMOS architecture employed in its design offers superior performance to older passive and active techniques. Linfinity's architecture employs highspeed adaptive elements for each channel, providing the fastest response possible. The channel bandwidth is typically 35MHz. The LX5122 compares favorably to older linear regulator approaches whose bandwidth's are dominated by the output compensation capacitor and are limited to the 500KHz bandwidth region (see further discussion in the Functional Description section). Linfinity's architecture also eliminates the output compensation capacitor typical in earlier terminator designs. Each is approved for use with SCSI-1, -2, -3, ULTRA and beyond -- providing the highest performance alternative available today. Another key improvement of LX5122 products lies in their ability to insure reliable, error free communications even in systems which do not necessarily adhere to recommended SCSI hardware design guidelines, such as the use of improper cable lengths and impedances. Frequently, this situation is not controlled by the peripheral or host designer and, when problems occur, they are the first to be made aware of these problems. The LX5122 architecture is much more tolerant of marginal system integrations. Recognizing the needs of portable and configurable peripherals, the LX5122 has a TTL compatible sleep/disable mode. Quiescent current is less than 150A in this mode. Reduced component count is also inherent in the LX5122 architecture. Traditional termination techniques require large stabilization and transient protection capacitors of up to 20F in value and size. The LX5122 architecture does not require these components, allowing all the cost savings associated with inventory, board space, assembly, reliability, and component costs. The LX5122 has multiple disables for full Plug and Play SCSI capability for Host Bus Adapters with 3 SCSI connectors. It also splits the upper 9 termination lines for mixing 16-bit (wide) and 8-bit (narrow) buses with minimal board trace capacitance.
K E Y F E AT U R E S
s Ultra-Fast Response For Fast-20 SCSI Applications s Plug and Play SCSI For Host Bus Adapters With 3 SCSI Connectors s Split Disconnect For Mixing 16-Bit (Wide) Or 8-Bit (Narrow) Buses s 35MHz Channel Bandwidth s Sleep-Mode Current Less Than 150A s Hot-Swap Compatible s NO External Compensation Capacitors s Compatible With Active Negation Drivers s Superior Pin-for-Pin Replacement For The UCC5622
NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.
PRODUCT HIGHLIGHT
RECEIVING W AV E F O R M - 2 0 M HZ
D R I V I N G WAV E F O R M - 2 0 M H Z
Receiver 1 Meter, AWG 28 LX5122 LX5268
Driver LX5122 LX5268
PA C K A G E O R D E R I N F O TJ (C) 0 to 125
DB Plastic SSOP 44-pin
LX5122CDB
NOTE: For An In-Depth Discussion On Applying SCSI, Request Linfinity Application Note: "Understanding The Single-Ended SCSI Bus"
Note: Available in Tape & Reel. Append the letter "T" to part number. (i.e. LX5122CDBT)
Copyright (c) 1999 Rev. 1.0 6/99
LINFINITY MICROELECTRONICS INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570
1
PRODUCT DATABOOK 1996/1997
LX5122
ULTRA 27-LINE, PLUG
P
AND
UltraMAX
PLAY SCSI TERMINATOR
D
ATA RODUCTION
S
HEET PA C K A G E P I N O U T S
T19 T20 T1 T2 W1 W2 T3 T4 T5 GND GND GND GND DISC1 DISC2 T6 T7 T8 T9 T10 T21 T22
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23
A B S O L U T E M A X I M U M R AT I N G S
(Note 1)
TermPwr Voltage ..................................................................................................... 7V Continuous Output Voltage Range .............................................................. 0 to 5.5V Continuous Disable Voltage Range .............................................................. 0 to 5.5V Operating Junction Temperature Plastic (PW & DB Packages) ......................................................................... 150C Storage Temperature Range ............................................................. -65C to +150C Solder Temperature (Soldering, 10 seconds) ................................................... 300C
Note 1. Exceeding these ratings could cause damage to the device.
T H E R M A L D ATA
PW PACKAGE: THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA DB PACKAGE: THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA 50C/W 50C/W
Junction Temperature Calculation: TJ = TA + (PD x JA). The JA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow.
T27 T26 T25 T18 N1 T17 T16 T15 N.C. GND GND GND GND VT T14 T13 T12 N.C. N.C. T11 T24 T23
DB PACKAGE (Top View)
R E C O M M E N D E D O P E R AT I N G C O N D I T I O N S Parameter
Termination Voltage High Level Disable Input Voltage Low Level Disable Input Voltage Operating Virtual Junction Temperature Range LX5122C Note 2. Range over which the device is functional.
(Note 2)
Symbol
VTERM VIH VIL
Recommended Operating Conditions Min. Typ. Max.
4.0 2 0 0 5.5 VTERM 0.8 125
Units
V V V C
ELECTRICAL CHARACTERISTICS
Term Power = 4.75V unless otherwise specified. Unless otherwise specified, these specifications apply at the recommended operating ambient temperature of TA = 25C. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature.
Parameter
Output High Voltage TermPwr Supply Current
Symbol
VOUT ICC
Test Conditions
Min.
2.65
LX5122 Typ. Max.
2.85 12 635 50 -23 20 670 150 -24 -10 -10 1
Units
V mA mA A mA A A A MHz mA
Output Current Disable Input Current
DISC1 DISC2
IOUT IIN
Output Leakage Current Channel Bandwidth Termination Sink Current, per Channel
All data lines = open All data lines = 0.5V DISC1 and DISC2 < 0.8V VOUT = 0.2V DISC1 = 0V DISC2 = 0V DISC1 and DISC2 < 0.8V, VO = 0.2V VOUT = 4V
-20
BW ISINK
35 7
2
Copyright (c) 1999 Rev. 1.0 6/99
PRODUCT DATABOOK 1996/1997
UltraMAX
ULTRA 27-LINE, PLUG
P
AND
LX5122
PLAY SCSI TERMINATOR
D
ATA RODUCTION
S
HEET
BLOCK DIAGRAM
TERM POWER
CURRENT BIASING CIRCUIT
24mA CURRENT LIMITING CIRCUIT
DATA OUTPUT PIN DB(0)
VCC DISC1
VCC DISC2 2.85V
1.4V 1 OF 27 CHANNELS
FUNCTIONAL DESCRIPTION Cable transmission theory suggests that in order to optimize signal speed and quality, the termination should act both as an ideal voltage reference when the line is released (de-asserted) and as an ideal current source when the line is active (asserted). Common active terminators, which consist of Linear Regulators in series with resistors (typically 110), are a compromise. As the line voltage increases, the amount of current decreases linearly by the equation V = I * R. The UltraMAX LX5122, with its unique new architecture, applies the maximum amount of current regardless of line voltage until the termination high threshold (2.85V) is reached. Acting as a near ideal line terminator, the LX5122 closely reproduces the optimum case when the device is enabled. To enable the device the DISC1 and DISC2 pins must be driven per the above table. During this mode of operation, quiescent current is 12mA and the device will respond to line demands by delivering 24mA on T19-T27 assertion and by imposing 2.85V on de-assertion. Disable mode places the device in a sleep state, Disabled where a meager 150A of quiescent current is Enabled consumed. Additionally, all outputs are in a HiDisabled Z (impedance) state. Sleep mode can be used Enabled for power conservation or to completely eliminate Enabled the terminator from the SCSI chain. An additional feature of the LX5122 is its comEnabled patibility with active negation drivers. Enabled
POWER UP / POWER DOWN FUNCTION TABLE
DISC1 L H H L L L L L L L L DISC2 H L H L L L L L L L L W1 DC DC DC H H H H L L L L W2 DC DC DC H H L L H H L L N1 DC DC DC H L H L H L H L T1-T18 Enabled Disabled Disabled Enabled Enabled Enabled Disabled Enabled Disabled Disabled Disabled
Enabled Enabled Disabled Disabled
Copyright (c) 1999 Rev. 1.0 6/99
3
PRODUCT DATABOOK 1996/1997
LX5122
ULTRA 27-LINE, PLUG
P
AND
UltraMAX
PLAY SCSI TERMINATOR
D
ATA RODUCTION
S
HEET
P L U G A N D P L AY S C S I D I A G R A M
Internal Narrow
Internal Wide External Wide LX5122
For Plug and Play SCSI auto-termination diabling, connect pin 50 of the External Wide SCSI connector to W1 of the LX5122, connect pin 50 of the Internal Wide SCSI connector to W2 of the LX5122, and connect pin 22 of the Internal Narrow connector to N1 of the LX5122.
UltraMAX is a trademark of Linfinity Microelectronics Inc.
PRODUCTION DATA - Information contained in this document is proprietary to LinFinity, and is current as of publication date. This document may not be modified in any way without the express written consent of LinFinity. Product processing does not necessarily include testing of all parameters. Linfinity reserves the right to change the configuration and performance of the product and to discontinue product at any time.
4
Copyright (c) 1999 Rev. 1.0 6/99

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