UCC5629
DESCRIPTION
The UCC5629 Multimode SCSI Terminator provides a smooth transition
into the next generation of the SCSI Parallel Interface (SPI-2). It automati
-
cally senses the bus, via DIFFB, and switches the termination to either sin
gle ended (SE) or low voltage differential (LVD) SCSI, dependent on which
type of devices are connected to the bus. The UCC5629 can not be used
on a HVD, EIA485, differential SCSI bus. If the UCC5629 detects a HVD
SCSI device, it switches to a high impedance state.
The Multimode terminator contains all functions required to terminate and
auto detect and switch modes for SPI-2 bus architectures. Single Ended
and Differential impedances and currents are trimmed for maximum effec
tiveness. Fail Safe biasing is provided to insure signal integrity. Device/Bus
type detection circuitry is integrated into the terminator to provide automatic
switching of termination between single ended and LVD SCSI and a high
impedance for HVD SCSI. The multimode function provides all the perform
ance analog functions necessary to implement SPI-2 termination in a sin
gle monolithic device.
The UCC5629 is offered in a 48 pin LQFP package for a temperature range
of 0°C to 70°C.
Multimode SCSI 14 Line Terminator
FEATURES
•
Auto Selection Single Ended (SE) or
Low Voltage Differential (LVD)
Termination
•
Meets SCSI-1, SCSI-2, SCSI-3, SPI,
Ultra (Fast-20), Ultra2 (SPI-2 LVD)
and Ultra3 Standards
•
2.7V to 5.25V Operation
•
Differential Failsafe Bias
•
Thermal packaging for low junction
temperature and better MTBF.
•
Reversed Polarity Disconnect
SLUS444 - NOVEMBER 1999
REF
1.25V
36
DISCNCT
REG
L1+
L14–
L14+
SOURCE/SINK REGULATOR
REF
1.3V
4.7µF .
35 DIFFSEN
–15mA ≤ I
SOURCE
≤ –5mA
50µA ≤ I
SINK
≤ 200µA
HPD
SE
34DIFFB
0.6V
2.15V
52.5
2
52.5
1
110
10
REF
2.7V
SE GND SWITCH
3TRMPWR
25
GND
4-9
HS/GND
28-33
HS/GND
L1–
124
52.5
12
52.5
11
110
124
10µA
1.3V
(NOISE LOAD)
MODE
SE
LVD
DISCNCT
ALL SWITCHES
UP
DOWN
OPEN
SE GND SWITCH
56mV
–+
+–
–+
56mV
56mV
56mV
+–
27
26
LVD
BLOCK DIAGRAM
UDG-99156
2
UCC5629
(TOP VIEW)
FQP Package
ABSOLUTE MAXIMUM RATINGS
TRMPWR Voltage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +6V
Signal Line Voltage . . . . . . . . . . . . . . . . . . . . . 0V to TRMPWR
Package Dissipation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2W
Storage Temperature . . . . . . . . . . . . . . . . . . . –65°C to +150°C
Junction Temperature. . . . . . . . . . . . . . . . . . . –55°C to +150°C
Lead Temperature (Soldering, 10 sec.). . . . . . . . . . . . . +300°C
Recommended Operating Conditions . . . . . . . . . 2.7V to 5.25V
Currents are positive into negative out of the specified terminal.
Note: Consult Packaging Section of Databook for thermal limi
-
tations and considerations of package.
RECOMMENDED OPERATING CONDITIONS
TRMPWR Voltage . . . . . . . . . . . . . . . . . . . . . . . . 2.7V to 5.25V
Temperature Ranges . . . . . . . . . . . . . . . . . . . . . . 0°C to +70°C
12
11
10
9
13
8
7
6
5
4
321
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
313233
34
35
36
48
47
46
45
44
43
42
41
40
39
38
37
TRMPWR
HS/GND
HS/GND
HS/GND
L1–
L1+
REG
HS/GND
HS/GND
HS/GND
L9–
L10+
L9+
DIFFSENS
DISCNCT
HS/GND
DIFFB
HS/GND
HS/GND
GND
SE
LVD
HS/GND
HS/GND
HS/GND
L4+
L3–
L3+
L2–
L2+
L4–
L5+
L6+
L5–
L7+
L6–
L7–
L11+
L11–
L10–
L12–
L13+
L12+
L14+
L14–
L13–
L8–
L8+
CONNECTION DIAGRAMS
ELECTRICAL CHARACTERISTICS
Unless otherwise stated, these specifications apply for TA=TJ= 0°C to 70°C,
TRMPWR = 3.3V.
PARAMETER TEST CONDITIONS MIN TYP MAX UNITS
TRMPWR Supply Current Section
TRMPWR Supply Current LVD Mode 20 25 mA
SE Mode 1.6 10 mA
Disabled Terminator 250 400
A
Regulator Section
1.25V Regulator LVD Mode 1.15 1.25 1.35 V
1.25V Regulator Source Current V
REG
= 0V –375 –700 –1000 mA
1.25V Regulator Sink Current V
REG
= 3.3V 170 300 700 mA
1.3V Regulator Diff Sense 1.2 1.3 1.4 V
1.3V Regulator Source Current V
REG
= 0V –15 –5 mA
1.3V Regulator Sink Current V
REG
= 3.3V 50 200 A
2.7V Regulator SE Mode 2.5 2.7 3.0 V
2.7V Regulator Source Current V
REG
= 0V –375 –700 –1000 mA
2.7V Regulator Sink Current V
REG
= 3.3V 170 300 700 mA
Differential Termination Section
Differential Impedance 100 105 110
Common Mode Impedence (Note 2) 110 150 165
Differential Bias Voltage 100 125 mV
Common Mode Bias 1.15 1.25 1.35 V
Output Capacitance Single Ended Measurement to Ground (Note 1) 3 pF
Loading...