UltraMAX
TM
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
T
H E
I
N F I N I T E
P
O W E R
O F
I
P
N N O VA T I O N
R E L I M I N A R Y
DESCRIPTION
The LX5245/5246/5247 ICs are Low Voltage Differential (LVD) Terminators designed 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.
D
A T A
S
H E E T
K E Y F E AT U R E S
■ 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
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.
NOTE: For current data & package dimensions, visit our web site: http://www.linfinity.com.
PRODUCT HIGHLIGHT
B U S V O LTA G E 1
V OD
VOD = V(-) - V(+), Logic = 0
V(+)
NEGATED
VCM
100mV
0V
V(-)
-100mV
LX5245/46/47
LX5245/46/47
PA C K A G E O R D E R I N F O
TA (°C)
0 to 70
PW Plastic TSSOP
24-pin
28-PIN
LX5245CPW
LX5246CPW
Note: All surface-mount packages are available in Tape & Reel.
Append the letter "T" to part number. (i.e. LX5245CPWT)
Copyright © 2000
Rev. 0.6 10/00
LINFINITY MICROELECTRONICS INC.
11861 WESTERN AVENUE, GARDEN GROVE, CA. 92841, 714-898-8121, FAX: 714-893-2570
1
PRODUCT DATABOOK 1996/1997
UltraMAX
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
P
R E L I M I N A R Y
A B S O L U T E M A X I M U M R AT I N G S
D
A T A
S
H E E T
PACKAGE PIN OUTS
(Note 1)
LX5245/46 CPW
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
N.C.
1+
12+
23+
34+
4DIFFB
DIFFSENSE
GND
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.
T H E R M A L D ATA
1
24
2
23
3
22
4
21
5
20
6
19
7
18
8
17
9
16
10
15
1
1
12
14
13
VTERM
99+
88+
77+
66+
55+
DISC
24L PW PACKAGE (Top View)
("N.C." = No Internal Connections)
PW PACKAGE:
THERMAL RESISTANCE-JUNCTION TO AMBIENT, θJA
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.
DIFFSENSE / POWER UP / POWER DOWN FUNCTION TABLE
2
LX5245/LX5247
DISCONNECT
LX5246
DISCONNECT
DIFFSENSE
L
L
L
H
Open
H
H
H
L
Open
L < 0.5V
0.7V to 1.9V
H > 2.4V
X
X
Outputs
Status
Type
Disable
Enable
Disable
Disable
Disable
HiZ
LVD
HiZ
HiZ
HiZ
Quiescent
Current
2mA
21mA
2mA
10µA
10µA
Copyright © 2000
Rev. 0.6 10/00
PRODUCT DATABOOK 1996/1997
UltraMAX
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
P
R E L I M I N A R Y
D
A T A
S
H E E T
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
Symbol
Termpwr Voltage
Signal Line Voltage
Disconnect Input Voltage
Operating Junction Temperature Range
LX5245 / 5246/5247
(Note 2)
Recommended Operating Conditions
Min.
Typ.
Max.
VTERM
Units
3.0
0
0
5.25
5.0
VTERM
V
V
V
0
70
°C
Note 2. Range over which the device is functional.
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
LX5245 / 5246
Min. Typ.
Max.
Units
LVD Terminator Section
TermPwr Supply Current
LVD ICC
Common Mode Voltage
Offset Voltage (fail safe bias voltage)
Differential Terminator Impedance
Common Mode Impedance
Output Capacitance
Output Leakage
VOM
VOS
ZD
ZCM
Co
ILeak
Mode Change Delay
tDF
All term lines = Open
DISCONNECT: LX5245/47 = H, LX5246 = L
Open circuit between - and + (see Note 3)
VOD = -1V to 1V
0V to 2.5V
DISCONNECT: LX5245/47 = H, LX5246 = L
DISCONNECT: LX5245/47 = H, LX5246 = L, VLINE = 0 to 4V, TA=25°C
DISCONNECT: LX5245/47 = H, LX5246 = L, VTERM = 0V, VLINE = 2.7V
DIFFSENSE = 1.4V to 0V
21
5
1.125 1.25
100 112
100 105
100 200
2.5
0
1
100 150
25
mA
10
µA
1.375 V
125 mV
110
Ω
300
Ω
pF
2
µA
µA
ms
1.2
5.0
1.4
15.0
200
10
V
mA
µA
µA
2.0
10
10
V
µA
µA
DIFFSENSE Section
DIFFSENSE Output Voltage
DIFFSENSE Output Source Current
DIFFSENSE Sink Current
DIFFSENSE Output Leakage
VDIFF
IDIFF
ISINK(DIFF)
ILEAK(DIFF)
DIFFSENSE = 0V
VIN = 2.75V
DISCONNECT: LX5245/47 = H, LX5246 = L, TA = 25°C
1.3
DISCONNECT Section
DISCONNECT Threshold
Input Current
VTH
IIH
0.8
DISCONNECT: LX5245/47 = 0V
DISCONNECT: LX5246 = 3.3V
Note 3. Open circuit failsafe voltage.
Copyright © 2000
Rev. 0.6 10/00
3
PRODUCT DATABOOK 1996/1997
UltraMAX
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
P
D
R E L I M I N A R Y
A T A
S
H E E T
BLOCK DIAGRAM
Power ON
VTERMPWR
DISC
1 of 9
1.07mA
Internal VREF
1.30V
HVD
LVD
2cm
200
LVD
1.25V
2D(-)
52.5
2D(+)
52.5
SE
HVD
LVD
LVD (+)
SE
10mA
DIFFSENSE
1.07mA
HVD
DIFF B
LVD (-)
Window
Comp.
LATCH
LVD
SE
Power ON
Power ON
& Mode
Change
Delay
FIGURE 1 — LX5245 Block Diagram
4
Copyright © 2000
Rev. 0.6 10/00
PRODUCT DATABOOK 1996/1997
UltraMAX
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
P
R E L I M I N A R Y
D
A T A
S
H E E T
FUNCTIONAL PIN DESCRIPTION
Pin
Designator
1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-1
Description
Negative signal termination lines.
1+, 2+, 3+, 4+, 5+, 6+, 7+, 8+, 9+ Positive signal termination lines.
VTERM
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 VTERM 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 VTERM pin.
DISC1
Enables / disables terminator. See Power Down Function Table for logic levels per device.
GND1
Terminator ground pin. Connect to ground.
DIFFSENSE1
DIFFB1
Copyright © 2000
Rev. 0.6 10/00
Used to drive DIFFSENS output 3V @ 10 mt. Usually connected through a 20kOhm resistor to DIFF B
pin.
Used to detect the SCSI BUS mode (LUD, HUD, SE)
5
PRODUCT DATABOOK 1996/1997
UltraMAX
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
P
R E L I M I N A R Y
D
A T A
S
H E E T
A P P L I C AT I O N S C H E M AT I C
H O S T
T E R M P O W E R
V
1 1 +
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
D IS C O N N E C T
P E R IP H E R A L
1 -
9 9 +
V
4 .7 µ F
1 -
G N D
V
9 -
9 -
9 +
9 +
V
1 1 +
9 -
9 +
9 +
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
C o n tr o l L in e s ( 9 )
9 -
D IF F B *
G N D
D IF F B *
1 1 +
D IF F S E N S E
M /S
D IF F S E N S E
D IF F B *
D IS C O N N E C T
G N D
4 .7 µ F
D IS C O N N E C T
D IF F S E N S E
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
D a ta L in e s ( 9 )
T E R M
M /S
V
1 +
D IS C O N N E C T
M /S
G N D
D IF F B *
1 1 +
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
M /S
D IF F S E N S E
D IF F B *
T E R M
D IS C O N N E C T
D IS C O N N E C T
D IF F S E N S E
G N D
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
D a ta L in e s ( 9 )
9 9 +
D IS C O N N E C T
M /S
V
1 +
T E R M P O W E R
D IS C O N N E C T
D IF F S E N S E
D IF F B *
M /S
G N D
FIGURE 2 — Linfinity ONLY Application Schematic
6
Copyright © 2000
Rev. 0.6 10/00
PRODUCT DATABOOK 1996/1997
UltraMAX
LX5245/5246/5247
9 - L I N E LV D S C S I T E R M I N A T O R
P
R E L I M I N A R Y
D
A T A
S
H E E T
A P P L I C AT I O N S C H E M AT I C
H O S T
T E R M P O W E R
V
1 1 +
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
D IS C O N N E C T
P E R IP H E R A L
1 +
9 9 +
D IS C O N N E C T
D IS C O N N E C T
D IF F S E N S E
N .C .*
P in 1
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
D a ta L in e s ( 9 )
9 9 +
D IS C O N N E C T
G N D
V
1 -
T E R M P O W E R
D IF F B
2 0 k
D IF F S E N S E
2 0 k
0 .1 µ F
0 .1 µ F
4 .7 µ F *
G N D
D IF F B
N .C .*
P in 1
V
4 .7 µ F *
1 1 +
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
4 .7 µ F
1 -
9 -
9 +
9 +
4 .7 µ F
D IS C O N N E C T
D IF F S E N S E
D IF F S E N S E
N .C .*
P in 1
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
D a ta L in e s ( 9 )
9 -
D IS C O N N E C T
G N D
V
1 +
G N D
D IF F B
D IF F B
4 .7 µ F *
N .C .*
P in 1
V
4 .7 µ F *
1 1 +
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
1 -
9 -
9 +
9 +
D IS C O N N E C T
D IF F S E N S E
D IF F S E N S E
N .C .*
P in 1
T E R M
L X 5 2 4 5
L X 5 2 4 6
L X 5 2 4 7
C o n tr o l L in e s ( 9 )
9 -
D IS C O N N E C T
G N D
V
1 +
G N D
D IF F B
D IF F B
4 .7 µ F *
N .C .*
P in 1
4 .7 µ F *
* T h e c a p a c ito r o n P in 1 c a n b e p la c e d o n th e L X 5 2 4 5 C P W , L X 5 2 4 6 C P W
o r th e L X 5 2 4 7 C P W
to b e p in - c o m p a tib le w ith o th e r d e v ic e s . T h is V
R E G
/R E F c a p a c ito r is n o t r e q u ir e d .
FIGURE 3 — Suggested Linfinity LX5245/5246/5247 Universal Application Schematic
(Please Reference Manufacturer's Current Data Sheet To Ensure Compatibility)
UltraMAX is a trademark of Linfinity Microelectronics Inc.
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.
Copyright © 2000
Rev. 0.6 10/'00
7