SS8218
Ultra160 Multi-mode LVD/SE SCSI Terminator
Features
General Description
ꢀAuto-selectable multi-mode Single-Ended
or LVD Termination
The SS8218 Multi-mode LVD/SE SCSI terminator pro-
vides a smooth transition to the next generation of
the SCSI Parallel Interface (SPI-3). It automatically
senses the bus, via DIFFSENS, and switches the ter-
mination to either single-ended (SE) or low voltage
differential (LVD) SCSI, dependent on which type of
devices are connected to the bus. If the SS8218 de-
tects a HVD SCSI device, it switches to a high imped-
ance state. For a 16-bit Wide SCSI bus to be opera-
tional, three SS8218 terminators are needed.
ꢀMeets SCSI-1, SCSI-2, SCSI-3 SPI Ultra
(Fast-20), Ultra 2(SPI-2 LVD), Ultra160 (SPI-3
LVD) standards.
ꢀSupports active negation
ꢀ3pF channel capacitance
ꢀThermal protection
ꢀHot-swap compatible
ꢀ5% tolerance on SE and LVD termination
resistance
ꢀ28 and 36 pin SSOP package
ꢀ28 Pin SSOP: Pin Compatible with DS2119
ꢀ36 Pin SSOP: Pin Compatible with DS2118,
LX5241 and UCC5630
The Multi-mode terminator contains all functions re-
quired to terminate and auto detect and switch modes
for SCSI Parallel Interface (SPI) bus architectures. For
the SE termination, one regulator and nine precision
110ohm resistors are used. For the LVD termination,
the SS8218 integrates 18 regulated supplies with nine
precision resistor strings.
Applications
ꢀServer and workstation
ꢀHigh-end PC
ꢀIndustrial PC
ꢀDisk Array (RAID)
ꢀSCSI cable
Pin Configuration
36
35
1
2
3
4
5
TPWR
HVD
VREF
NC
34 LVD
NC
33
R1+
R1-
SE
28
27
26
25
24
23
1
2
TPWR
VREF
R1+
32
R9-
TPWR
R9-
31
6
7
R2+
R2-
R9+
R1-
3
30
R8-
NC/HS GND
R9+
4
R2+
R2-
29
28
27
HS/GND
HS/GND
8
9
R8+
5
R8-
HS/GND
NC/HS GND
R8+
6
10
11
12
HS/GND
HS/GND
R3+
R3+
R3-
22 NC/HS GND
21 R7-
7
26 HS/GND
8
25
R3-
R7-
R4+
20
9
R7+
24
R4+ 13
R7+
R4-
R5+
19 R6-
10
11
12
13
14
23
R4-
R6-
R6+
18
17
22
15
16
17
R5+
R5-
R6+
DIFFB
R5-
21 DIFFB
16 DIFFSENSE
15 M/S
DISCNCT
GND
20
19
DIFFSENSE
M/S
DISCNCT
GND
14
18
28Pin SSOP/TSSOP
36Pin SSOP
Rev.2.01 6/06/2003
www.SiliconStandard.com
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