Datasheet LX5246CPW, LX5245CPW, LX5247CPW Datasheet (Microsemi Corporation)

9-LINE LVD SCSI TERMINATOR

PRELIMINARY DATA SHEET

THE INFINITE POWER OF INNOVATION

LX5245/5246/5247

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

■Mention 5249 as LVD only terminator

with pinout compatable with industry
standard multi-mode terminators

■ Pin compatable with unitrode UCC5640

PRODUCT HIGHLIGHT

The LX5245/5246/5247 ICs are Low Volt­age Differential (LVD) Terminators de-

signed to comply with the LVD termination
specification in the SPI-2 document. The
LX5245/5246/5247 are designed specifically
for LVD applications. Because the LX5245/
5246/5247 support only LVD, they have lower
output capacitance than multimode termina­tors such as the LX5240.

The LX5245/5246/5247 Utilize

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 LX5245/5246/5247 Are
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 LX5245/
5246/5247 output will be HiZ. If the
DIFFSENSE line is HIGH, indicating a high
voltage differential device the LX5245/5246/
5247 output will be HiZ.

The LX5245/5246/5247 ICs Have A TTL
Compatible DISCONNECT Pin. The

LX5245/47 is active LOW and the LX5246
is active HIGH. 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

LX5245/46/47 LX5245/46/47

BUS VOLTAGE1 V

OD

UltraMAX

TM

0 to 70

LX5245CPW
LX5246CPW

PACKAGE ORDER INFO

T

A

(°C)

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

Append the letter "T" to part number. (i.e. LX5245CPWT)

Plastic TSSOP
24-pin
28-PIN

Copyright © 2000

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.

PW

9-LINE LVD SCSI TERMINATOR

LX5245/5246/5247

PRODUCT DATABOOK 1996/1997

Copyright © 2000

Rev. 0.6 10/00

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.

PW PACKAGE:

THERMAL RESISTANCE-JUNCTION TO AMBIENT,

θθ

θθ

θ

JA

100°C/W

Junction Temperature Calculation: TJ = TA + (PD x θJA).
The θJA numbers are guidelines for the thermal performance of the device/pc-board
system. All of the above assume no ambient airflow.

THERMAL DATA

ABSOLUTE MAXIMUM RATINGS (Note 1)

PACKAGE PIN OUTS

24L PW PACKAGE (Top View)

("N.C." = No Internal Connections)

V

TERM

9­9+
8­8+
7­7+
6­6+
5­5+
DISC

1 24

223

322

421

520

619

718

817

916

1015

1 1 14

1213

N.C.

1+

1-

2+

2-

3+

3-

4+

4-

DIFFB

DIFFSENSE

GND

LX5245/LX5247 LX5246

DIFFSENSE

Outputs Quiescent

DISCONNECT DISCONNECT Status Type Current

L H L < 0.5V Disable HiZ 2mA

L H 0.7V to 1.9V Enable LVD 21mA

L H H > 2.4V Disable HiZ 2mA

H L X Disable HiZ 10µA

Open Open X Disable HiZ 10µA

DIFFSENSE / POWER UP / POWER DOWN FUNCTION TABLE

LX5245/46 CPW

9-LINE LVD SCSI TERMINATOR

LX5245/5246/5247

PRODUCT DATABOOK 1996/1997

3

Copyright © 2000

Rev. 0.6 10/00

PRELIMINARY DATA SHEET

UltraMAX

Termpwr Voltage V

TERM

Signal Line Voltage
Disconnect Input Voltage
Operating Junction Temperature Range

LX5245 / 5246/5247

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: LX5245/47 = L, LX5246 = H. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to
the ambient temperature.)

Parameter

Symbol

Test Conditions Units

LX5245 / 5246

Min. Typ. Max.

21 25 mA

5 10 µA

1.125 1.25 1.375 V
100 112 125 mV
100 105 110 Ω
100 200 300 Ω

2.5 pF
0 2 µA
1 µA

100 150 ms

LVD Terminator Section

TermPwr Supply Current LVD ICCAll term lines = Open

DISCONNECT: LX5245/47 = H, LX5246 = L

Common Mode Voltage V

OM

Offset Voltage (fail safe bias voltage) V

OS

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: LX5245/47 = H, LX5246 = L
Output Leakage I

Leak

DISCONNECT: LX5245/47 = H, LX5246 = L, V

LINE

= 0 to 4V, TA=25°C

DISCONNECT: LX5245/47 = H, LX5246 = L, 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

IH

DISCONNECT: LX5245/47 = 0V

DISCONNECT: LX5246 = 3.3V

0.8 2.0 V
10 µA
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

LEAK(DIFF)

DISCONNECT: LX5245/47 = H, LX5246 = L, TA = 25°C

Note 3. Open circuit failsafe voltage.

9-LINE LVD SCSI TERMINATOR

LX5245/5246/5247

PRODUCT DATABOOK 1996/1997

Copyright © 2000

Rev. 0.6 10/00

4

PRELIMINARY DATA SHEET

UltraMAX

BLOCK DIAGRAM

FIGURE 1 — LX5245 Block Diagram

Internal V

REF

1.30V

Power ON

2D(-)

52.5

2D(+)

52.5

2cm

200

Window
Comp.

LATCH

Power ON

& Mode

Change

Delay

HVD

LVD

SE

Power ON

10mA

V

TERMPWR

DISC

DIFFSENSE

DIFF B

SE

HVD

LVD

LVD (+)

LVD (-)

1 of 9

1.07mA

1.07mA

LVD

1.25V

SE

HVD

LVD

9-LINE LVD SCSI TERMINATOR

LX5245/5246/5247

PRODUCT DATABOOK 1996/1997

5

Copyright © 2000

Rev. 0.6 10/00

PRELIMINARY DATA SHEET

UltraMAX

1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-1 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 impedance (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 high-frequency
decoupling with 0.1µF capacitors right at V

TERM

pin.

DISC1 Enables / disables terminator. See Power Down Function Table for logic levels per device.

GND1 Terminator ground pin. Connect to ground.

DIFFSENSE1 Used to drive DIFFSENS output 3V @ 10 mt. Usually connected through a 20kOhm resistor to DIFF B

pin.

DIFFB1 Used to detect the SCSI BUS mode (LUD, HUD, SE)

Pin

Designator Description

FUNCTIONAL PIN DESCRIPTION

9-LINE LVD SCSI TERMINATOR

LX5245/5246/5247

PRODUCT DATABOOK 1996/1997

Copyright © 2000

Rev. 0.6 10/00

6

PRELIMINARY DATA SHEET

UltraMAX

APPLICATION SCHEMATIC

FIGURE 2 — Linfinity ONLY Application Schematic

1-V

TERM

GND

1+

LX5245
LX5246
LX5247

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

4.7µF 4.7µF

TERMPOWER

DISCONNECT

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

9-LINE LVD SCSI TERMINATOR

LX5245/5246/5247

PRODUCT DATABOOK 1996/1997

7

Copyright © 2000

Rev. 0.6 10/'00

PRELIMINARY DATA SHEET

UltraMAX

APPLICATION SCHEMATIC

UltraMAX is a trademark of Linfinity Microelectronics Inc.

FIGURE 3 — Suggested Linfinity LX5245/5246/5247 Universal Application Schematic

(Please Reference Manufacturer's Current Data Sheet To Ensure Compatibility)

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

4.7µF*

GND

1+

LX5245
LX5246
LX5247

DISCONNECT

N.C.*

Pin 1

DIFFB

9­9+

DIFFSENSE

1-V

TERM

4.7µF*

GND

1+

DISCONNECT

N.C.*

Pin 1

DIFFB

9­9+

DIFFSENSE

TERMPOWER

DISCONNECT

1-V

TERM

4.7µF*

GND

1+

DISCONNECT

N.C.*

Pin 1

DIFFB

9­9+

DIFFSENSE

20k

0.1µF

HOST

0.1µF

20k

Data Lines (9)

Data Lines (9)

Control Lines (9)

PERIPHERAL

TERMPOWER

DISCONNECT

V

TERM

GND

DISCONNECT

4.7µF*

N.C.*

Pin 1

4.7µF*

N.C.*

Pin 1

4.7µF*

N.C.*

Pin 1

1­1+

9­9+

1­1+

9­9+

DIFFB

DIFFSENSE

V

TERM

GND

DISCONNECT

1­1+

9­9+

DIFFB

DIFFSENSE

V

TERM

GND

DISCONNECT

1­1+

9­9+

DIFFB

DIFFSENSE

* The capacitor on Pin 1 can be placed on the LX5245CPW, LX5246CPW or the LX5247CPW to be pin-compatible with other devices. This V

REG

/REF capacitor is not required.

4.7µF 4.7µF

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247

LX5245
LX5246
LX5247