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LIN D O C #: 5121
UltraMAX
T
HE
TM
LX5121
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 LX5121 Plug and Play UltraMAXTM terminator represents next-generation technology for SCSI termination applications. The lowvoltage BiCMOS architecture employed in its design offers superior performance to older passive and active techniques. Linfinity's architecture employs high-speed adaptive elements for each channel, providing the fastest response possible. The channel bandwidth is typically 35MHz. The LX5121 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 LX5121 products lies in their ability to ensure reliable, errorfree 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 LX5121 architecture is much more tolerant of marginal system integrations. Recognizing the needs of portable and configurable peripherals, the LX5121 has a TTL compatible sleep/disable mode. Typically, quiescent current is less than 150A in this mode. Reduced component count is also inherent in the LX5121 architecture. Traditional termination techniques require large stabilization and transient protection capacitors of up to 20F in value and size. The LX5121 architecture does not require these components, allowing all the cost savings associated with inventory, board space, assembly, reliability, and component costs. The LX5121 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 16bit (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 UCC5621
NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.
PRODUCT HIGHLIGHT
R E C E I V I N G 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 HZ
Receiver 1 Meter, AWG 28 LX5121 LX5268
Driver LX5121 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
LX5121CDB
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. LX5121CDBT)
Copyright (c) 1999 Rev. 1.0 5/99
LINFINITY MICROELECTRONICS INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570
1
P R O D U C T D ATA B O O K 1 9 9 6 / 1 9 9 7
LX5121
ULTRA 27-LINE, PLUG
P
AND
UltraMAX
PLAY SCSI TERMINATOR
D
ATA RODUCTION
S
HEET
A B S O L U T E M A X I M U M R AT I N G S
(Note 1)
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
TermPwr Voltage ..................................................................................................... 7V Continuous Output Voltage Range .............................................................. 0 to 5.5V Continuous Disable Voltage Range .............................................................. 0 to 5.5V Operating Junction Temperature Plastic (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
DB PACKAGE: THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA 50C/W
Junction Temperature Calculation: TJ = T A + (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 LX5121C 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
LX5121 Typ. Max.
2.85 12 635 50 -22 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 = 0.2V Disable Pins 1 & 2 < 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 5/99
P R O D U C T D ATA B O O K 1 9 9 6 / 1 9 9 7
UltraMAX
ULTRA 27-LINE, PLUG
P
AND
LX5121
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 reproduces the optiPOWER UP / POWER DOWN FUNCTION TABLE theory suggests that in mum case when the DISC1 DISC2 W1 W2 N1 T1-T18 T19-T27 order to optimize sigdevice is enabled. To nal speed and quality, enable the device the H L DC DC DC Enabled Disabled the termination DISC1 and DISC2 pins L H DC DC DC Disabled Enabled should act both as an must be driven per the ideal voltage referabove table. During L L DC DC DC Disabled Disabled ence when the line is this mode of operation, H H H H H Enabled Enabled released (de-asserted) quiescent current is H H H H L Enabled Enabled and as an ideal current 12mA and the device H H H L H Enabled Enabled source when the line will respond to line deH H H L L Disabled Enabled is active (asserted). mands by delivering Common active termi24mA on assertion and H H L H H Enabled Enabled nators, which consist by imposing 2.85V on H H L H L Disabled Enabled of Linear Regulators in de-assertion. Disable H H L L H Disabled Disabled series with resistors mode places the device H H L L L Disabled Disabled (typically 110), are a in a sleep state, where compromise. As the a meager 150A of quiline voltage increases, the amount of current decreases linearly escent current is consumed. Additionally, all outputs are in by the equation V = I * R. The UltraMAX LX5121, with its a Hi-Z (impedance) state. Sleep mode can be used for power unique new architecture, applies the maximum amount of conservation or to completely eliminate the terminator from current regardless of line voltage until the termination high the SCSI chain. threshold (2.85V) is reached. An additional feature of the LX5121 is its compatibility with Acting as a near ideal line terminator, the LX5121 closely active negation drivers.
Copyright (c) 1999 Rev. 1.0 5/99
3
P R O D U C T D ATA B O O K 1 9 9 6 / 1 9 9 7
LX5121
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 LX5121
For Plug and Play SCSI auto-termination diabling, connect pin 50 of the External Wide SCSI connector to W1 of the LX5121, connect pin 50 of the Internal Wide SCSI connector to W2 of the LX5121, and connect pin 22 of the Internal Narrow connector to N1 of the LX5121.
UltraMAX is a trademark of Linfinity Microelectronics Inc.
PRODUCTION DATA - Information contained in this document is proprietary to Lin Finity, 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 5/99

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