UCC5672
SLUS414A - FEBRUARY 2000
FEATURES
•
Auto Selection Multi-Mode Single
Ended or Low Voltage Differential
Termination
•
2.7V to 5.25V Operation
•
Differential Failsafe Bias
•
Built-in SPI-3 Mode Change Filter/
Delay
•
Meets SCSI-1, SCSI-2, Ultra2 (SPI-2
LVD) and Ultra3/Ultra160 Standards
•
Supports Active Negation
•
3pF Channel Capacitance
Multimode (LVD/SE) SCSI 9 Line Terminator
1
27
16 DIFSENS
DIFSENS
REF 1.3V
ENABLE
3L1–
52
2L1+
52
L9–
L9+
56mV
+–
56mV
–+
124
110
SE GROUND
SWITCH
26
52
25
52
56mV
+–
56mV
–+
124
110
SE GROUND
SWITCH
REG
17
DIFFB
0.6V
2.1V
FILTER/
DELAY
28TRMPWR
TRMPWR
LVD REF
1.25V
SOURCE/SINK
REGULATORS
SE REF
2.7V
ENABLE
SW1
10µA
22
6HS/GND
HS/GND
14GND
13DISCNCT
SE
DISCNCT
HPD
LVD
UP
OPEN
DOWN
DOWN DOWN
UP
OPEN
OPEN
MODE SW1
OTHER
SWITCHES
HPD
LVD
SE
BLOCK DIAGRAM
UDG-99125
DESCRIPTION
The UCC5672 Multi-Mode Low Voltage Differential and Single Ended Ter
-
minator is both a single ended terminator and a low voltage differential ter
minator for the transition to the next generation SCSI Parallel Interface
(SPI-3). The low voltage differential is a requirement for the higher speeds
at a reasonable cost and is the only way to have adequate skew budgets.
The automatic mode select/change feature switches the terminator be
tween Single Ended or LVD SCSI Termination, depending on the bus
mode. If the bus is in High Voltage Differential Mode, the terminator lines
transition into a High Impedance state.
The UCC5672 is SPI-3, SPI-2, and SCSI-2 compliant. This device is of
fered in a 28 pin TSSOP package to minimize the footprint. The UCC5672
is also available in a 36 pin MWP package.
Note: Indicated pinout is for 28 pin TSSOP package.
2
UCC5672
ABSOLUTE MAXIMUM RATINGS
TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6V
Signal Line Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . 0V to 5V
Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C
Junction Temperature. . . . . . . . . . . . . . . . . . . –55°C to +150°C
Lead Temperature (Soldering, 10sec.) . . . . . . . . . . . . . +300°C
All voltages are with respect to GND.Currents are positive into,
negative out of the specified terminal. Consult Packaging Sec
tion of the Databook for thermal limitations and considerations
of packages.
RECOMMENDED OPERATING CONDITIONS
TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . . 2.7V to 5.25V
DIFFB
L6+
L8–
L8+
L7–
TRMPWR
L1+
L4–
L3+
L4+
L1–
L2+
L2–
REG
L3–
DIFSENS
L7+
L6–
L5+
GND 14
13
12
11
10
9
8
7
6
5
4
3
2
1
15
16
17
18
19
20
21
22
23
24
25
26
27
28
L5–
N/C
DISCNCT
L9–
L9+
TRMPWR
HS/GND
HS/GND
CONNECTION DIAGRAM
L3+
HS/GND
L9–
L9+
L8–
TRMPWR
N/C
N/C
HS/GND
L2–
HS/GND
L1+
L1–
L2+
REG
HS/GND
L3–
L8+
HS/GND
HS/GND
L4+
L4–
14
13
12
11
10
9
8
7
6
5
4
3
2
1
23
24
25
26
27
28
29
30
31
32
33
34
35
36
18
17
16
15
DIFF B
N/C
DIFSENS
19
20
21
22L5+
L5–
DISCNCT
GND
L7–
L7+
L6–
L6+
N/C
N/C
N/C
TSSOP-28 (TOP VIEW)
PWP Package
QSOP-36 (TOP VIEW)
MWP Package