Datasheet LX5249CPW, LX5249CDB, LX5248CPW Datasheet (Microsemi Corporation)

9-LINE LVD SCSI TERMINATOR

PRELIMINARY DATA SHEET

THE INFINITE POWER OF INNOVATION

LX5248/LX5249

DESCRIPTION KEY FEATURES

■2.5pF Typical Disabled Output

Capacitance

■Fast Response, No External Capacitors

Required

■5µA Supply Current In Disconnect Mode

■20mA Supply Current During Normal

Operation

■Logic Command Disconnects All

Termination Lines

■Diffsense Line Driver

■Current Limit And Thermal Protection

■Compatible With The Pending SPI-2 LVD

Specification

■Pin Compatible With Industry Standard

Multi-Mode Terminators

■For UCC5240 Pin Compatible LVD ONLY

Terminator (See LX5245/5246)

PRODUCT HIGHLIGHT

The LX5248/49 IC is a Low Voltage Dif­ferential (LVD) Terminator designed to

comply with the LVD termination specifica­tion in the SPI-2 document. The LX5248/
49 is designed specifically for LVD applica­tions. Because the LX5248/49 supports only
LVD, it has lower output capacitance than
multimode terminators such as the LX5240.

The LX5248/49 Utilizes Linfinity’s

UltraMAX Technology which delivers the

ultimate in SCSI bus performance while
saving component cost and board area.
Elimination of the external capacitors also
mitigates the need for a lengthy capacitor
selection process. The individual high band­width drivers also maximize channel sepa­ration and reduces channel-to-channel noise
and cross talk. The high-bandwidth
UltraMAX architecture insures ULTRA-2 per­formance, while providing a clear migration
path to ULTRA-3 and beyond.

When The LX5248/49 Is Enabled, The
Differential Sense (DIFFSENSE) Pin Sup­plies A Voltage Between 1.2V And 1.4V.

In application, the terminator DIFFSENSE
output is connected to the system
DIFFSENSE line. If there are no single ended
or HVD devices attached to the system the
LVD output will be enabled. If the
DIFFSENSE line is LOW, indicating a single
ended device, the LX5248/49 output will be
HiZ. If the DIFFSENSE line is HIGH, indi­cating a high voltage differential device the
LX5248/49 output will be HiZ.

The LX5248/49 IC Has A TTL Compat­ible DISCONNECT Pin. The LX5248/49 is

active LOW. During sleep mode, power
dissipation is reduced to a meager 5µA, while
also placing all outputs in a HI Z state. Also
during sleep mode, the DIFFSENSE function
is disabled and is placed in a HI Z state.

V

(+)

V

(-)

V

CM

VOD = V

(-)

- V

(+)

, Logic = 0

NEGATED

0V

100mV

-100mV

LX5248/49 LX5248/49

BUS VOLTAGE/ V

OD

UltraMAX

TM

Note: All surface-mount packages are available in Tape & Reel.

Append the letter "T" to part number. (i.e. LX5249CPWT)

Copyright © 2001
Rev. 0.6 10/00

1

11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: [phone]

LINFINITY MICROELECTRONICS INC.

NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.

0 to 70K LX5249CDBK LX5249CPWK LX5248CPW

PACKAGE ORDER INFORMATION

T

A

(°C)

DB

Plastic SSOP
36-pin

PW

Plastic TSSOP
24-pin

PW

Plastic TSSOP
28-pin

9-LINE LVD SCSI TERMINATOR

LX5248/LX5249

PRODUCT DATABOOK 1996/1997

Copyright © 2001

Rev. 0.6 1/01

2

PRELIMINARY DATA SHEET

UltraMAX

TermPwr Voltage..............................................................................................+6.5V

Signal Line Voltage...................................................................................0V to 6.5V

Differential Voltage...................................................................................0V to 6.5V

Operating Junction Temperature

Plastic (PW Package)...................................................................................150°C

Storage Temperature Range..............................................................-65°C to 150°C

Lead Temperature (Soldering, 10 seconds)....................................................300°C

Note 1.Exceeding these ratings could cause damage to the device. All voltages are with

respect to Ground. Currents are positive into, negative out of the specified
terminal.

ABSOLUTE MAXIMUM RATINGS (Note 1)

PACKAGE PIN OUTS

LX5248/LX5249

DIFFSENSE

Outputs Quiescent

DISCONNECT Status Type Current

L L < 0.5V Disable HiZ 2mA

L 0.7V to 1.9V Enable LVD 21mA

L H > 2.4V Disable HiZ 2mA

H X Disable HiZ 10µA

Open X Disable HiZ 10µA

DIFFSENSE / POWER UP / POWER DOWN FUNCTION TABLE

DB PACKAGE:

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

θθ

θθ

θ

JA

50°C/W

PW PACKAGE:

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

θθ

θθ

θ

JA

100°C/W

Junction Temperature Calculation: TJ = TA + (P

D

x θ

JA

).

The θ

JA

numbers are guidelines for the thermal performance of the device/pc-board

system. All of the above assume no ambient airflow.

THERMAL DATA

LX5249C ("N.C." = No Internal Connection)

DB PACKAGE (Top View)

N.C.
N.C.
N.C.

1+

1-

2+

2­HEATSINK/GND
HEATSINK/GND
HEATSINK/GND

3+

3-

4+

4-

5+

5-

DISCONNECT

GND

V

TERM

HVD
LVD
SE
9­9+
8­8+
HEATSINK/GND
HEATSINK/GND
HEATSINK/GND
7­7+
6­6+
DIFF B
DIFFSENSE
MASTER/SLAVE

136

235

334

433

532

631

730

829

928

10/ 27

11/ 26

12/ 25

13/ 24

14/ 23

15/ 22

16/ 21

17/ 20

18/ 19

LX5249CPW ("N.C." = No Internal Connection)

PW PACKAGE (Top View)

V

TERM

N.C.
9­9+
8­8+
7­7+
6­6+
DIFFSENSE
MASTER/SLAVE

1 24

223

322

421

520

619

718

817

916

10/ 15

11/ 14

12/ 13

1+

1-

2+

2-

3+

3-

4+

4-

5+

5-

DISCONNECT

GND

MASTER / DIFFSENSE Output

SLAVE Status Current

L* HI Z 0mA

H 1.3V 15mA Source

Open (Pull-up) 1.3V 15mA Source

MASTER / SLAVE FUNCTION TABLE

* When in Low state, terminator will detect state of DIFFSENSE line.

LX5248CPW ("N.C." = No Internal Connection)

PW PACKAGE (Top View)

V

TERM

LVD

9­9+
8­8+
N.C.
7­7+
6­6+
DIFFB
DIFFSENSE
MASTER/SLAVE

1 28

227

326

425

524

623

722

821

920

10/ 19

11/ 18

12/ 17

13/ 16

14/ 15

N.C.

1+

1-

2+

2-

N.C.

3+

3-

4+

4-

5+

5-

DISCONNECT

GND

9-LINE LVD SCSI TERMINATOR

LX5248/LX5249

PRODUCT DATABOOK 1996/1997

3

Copyright © 2001
Rev. 0.6 1/01

PRELIMINARY DATA SHEET

UltraMAX

Termpwr Voltage V

TERM

Signal Line Voltage
Disconnect Input Voltage
Operating Junction Temperature Range

LX5248 / LX5249

3.0 5.25 V

05.0V
0V

TERM

V

070°C

RECOMMENDED OPERATING CONDITIONS (Note 2)

Parameter

Symbol

Units

Recommended Operating Conditions

Min. Typ. Max.

ELECTRICAL CHARACTERISTICS

(Unless otherwise specified, these specifications apply over the operating ambient temperature range of 0°C ≤ TA ≤ 70°C. TermPwr = 3.3V,
DISCONNECT: LX5248/49 = L. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient
temperature.)

Parameter

Symbol

Test Conditions Units

LX5248 / 5249

Min. Typ. Max.

21 25 mA

510µA

1.125 1.25 1.375 V
100 112 125 mV

100 105 110 Ω
100 200 300 Ω

2.5 pF
02µA
1µA

100 150 ms

LVD Terminator Section

TermPwr Supply Current LVD ICCAll term lines = Open

DISCONNECT: LX5248/49 = H

Common Mode Voltage V

CM

Offset Voltage (Fail Safe Bias Voltage) V

FSB

Open circuit between - and + (see Note 3)
Differential Terminator Impedance ZDVOD = -1V to 1V
Common Mode Impedance Z

CM

0V to 2.5V
Output Capacitance CODISCONNECT: LX5248/49 = H
Output Leakage I

LEAK

DISCONNECT: LX5248/49 = H, V

LINE

= 0 to 4V, TA=25°C

DISCONNECT: LX5248/49 = H, V

TERM

= 0V, V

LINE

= 2.7V

Mode Change Delay t

DF

DIFFSENSE = 1.4V to 0V

Note 2. Range over which the device is functional.

DISCONNECT Threshold V

TH

Input Current I

IL

DISCONNECT: LX5248/49 = 0V

0.8 2.0 V
10 µA

DISCONNECT Section

DIFFSENSE Section

1.2 1.3 1.4 V

5.0 15.0 mA

200 µA

10 µA

DIFFSENSE Output Voltage V

DIFF

DIFFSENSE Output Source Current I

DIFF

DIFFSENSE = 0V

DIFFSENSE Sink Current I

SINK (DIFF)VIN

= 2.75V

DIFFSENSE Output Leakage I

SINK (DIFF)

DISCONNECT: LX5248/49 = H, TA = 25°C

Note 3. Open circuit failsafe voltage.

MASTER / SLAVE Threshold V

TH (MS)

Input Current I

IL (MS)

MASTER / SLAVE: LX5248/49 = 0V

0.8 2.0 V
10 µA

MASTER / SLAVE Section

9-LINE LVD SCSI TERMINATOR

LX5248/LX5249

PRODUCT DATABOOK 1996/1997

Copyright © 2001

Rev. 0.6 1/01

4

PRELIMINARY DATA SHEET

UltraMAX

BLOCK DIAGRAM

FIGURE 1 — LX5248 / 5249 Block Diagram

Internal V

REF

1.30V

Power ON

ZD(-)

52.5

ZD(+)

52.5

Zcm

200

Window
Comp.

LATCH

Power ON

& Mode

Change

Delay

HVD

LVD

SE

Power ON

10mA

V

TERMPWR

DIFFSENSE

DIFF B

SE

HVD
LVD

LVD (+)

LVD (-)

1 of 9

1.07mA

1.07mA

LVD

1.25V

SE

HVD
LVD

M/S

HVD
LVD
SE

9-LINE LVD SCSI TERMINATOR

LX5248/LX5249

PRODUCT DATABOOK 1996/1997

5

Copyright © 2001
Rev. 0.6 1/01

PRELIMINARY DATA SHEET

UltraMAX

FUNCTIONAL PIN DESCRIPTION

1-, 2-, 3-, 4-, 5-, 6-, 8-, 8-, 9-/ Negative signal termination lines.

1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+, 9+/ Positive signal termination lines.

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 impedence (big traces on PCB). Keeping distances
very short from the decoupling capacitors to the V

TERM

pin is also critical. The value of the
decoupling capacitor is somewhat layout dependant and some applications may benefit from high­frequency decoupling with 0.1µF capacitors right at V

TERM

pin.

DISCONNECT/ Enables / disables terminator. See Power Down Function Table for logic level per device.

GND/ Terminator ground pin. Connect to ground.

MASTER / SLAVE/ Sometimes 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.

DIFFSENSE/ This 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.

DIFFB/ Internally 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 LX5249, as it has an internal timer.

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

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

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

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

only, and not a true groung connection. It is recommended that these pins be connected to ground,
but can be left floating.

Pin

Designator Description

9-LINE LVD SCSI TERMINATOR

LX5248/LX5249

PRODUCT DATABOOK 1996/1997

Copyright © 2001

Rev. 0.6 1/01

6

PRELIMINARY DATA SHEET

UltraMAX

APPLICATION SCHEMATIC

UltraMAX is a trademark of Linfinity Microelectronics Inc.

FIGURE 2 — LX5248 / 5249 Application Schematic

PRELIMINARY DATA - Information contained in this document is pre-production data, and is proprietary to LinFinity. It may
not modified in any way without the express written consent of LinFinity. Product referred to herein is offered in sample form
only, and Linfinity reserves the right to change or discontinue this proposed product at any time.

1-V

TERM

GND

1+

LX5248
LX5249

DISCONNECT

M/S

DIFFB*

9­9+

DIFFSENSE

1-V

TERM

GND

1+

DISCONNECT

M/S

DIFFB*

9­9+

DIFFSENSE

TERMPOWER

DISCONNECT

1-V

TERM

GND

1+

DISCONNECT

M/S

DIFFB*

9­9+

DIFFSENSE

HOST

Data Lines (9)

Data Lines (9)

Control Lines (9)

PERIPHERAL

V

TERM

GND

DISCONNECT

M/S

1­1+

9­9+

1­1+

9­9+

DIFFB*

DIFFSENSE

V

TERM

GND

DISCONNECT

M/S

1­1+

9­9+

DIFFB*

DIFFSENSE

V

TERM

GND

DISCONNECT

M/S

1­1+

9­9+

DIFFB*

DIFFSENSE

* DIFFB Pin not present on LX5248CPW / 5249CPW Packages. Must connect DIFFSENS signal to DIFFSENSE pin on PW package.

4.7µF 4.7µF

TERMPOWER

DISCONNECT

LX5248
LX5249

LX5248
LX5249

LX5248
LX5249

LX5248
LX5249

LX5248
LX5249