SS7519 Datasheet, PDF (2/5 Pages) Silicon Standard Corp. – Multi-mode SCSI Terminator

SS7519
PIN DESCRIPTION
PIN
27,28
SYMBOL
TPWR
1
VREF
6,22
14
2,4,7,9,11,18
20,23,25
HS GND
GND
RxP
3,5,8,10,12 RxN
19,21,24,26
13
ISO
15
M/S
16
DIFFSENSE
17
DIF_CAP
DESCRIPTION
4.0V to 5.75V power input pin. Connect to SCSI bus power line. A
4.7µF capacitor and a 0.1µF high frequency capacitor are recommended
between TPWR and ground.
Reference Voltage. Must be decoupled with a 4.7µF capacitor to
ground as shown in Figure 1.
Heat Sink Ground. These should be connected to large area PC board
ground trace in order to increase the power dissipation capability.
Termination lines. These lines switch to hard ground in SE mode and
are the positive lines for LVD mode. All lines are in high impedance
when HVD is detected.
Termination lines. These lines switch to the active lines in SE mode
and are the negative lines for LVD mode. All lines are in high
impedance when HVD is detected.
Isolate pin. This pin used to shut down the terminator if the terminator
is not connected at the end of the bus. Connecting the pin to ground will
activate the terminator in normal operation. The terminator will be
disabled when the pin is in high state. An internal pull-down resistor
assures that the SS7519 will operate as normal if the ISO pin is left
floating.
Mode select pin. When pull high, master mode will enable the
DIFFSEN drive SCSI bus. The DIFFSENSE driver is off when this pin
is connected to ground.
Mode Sense pin. This signal will drive 1.3V to the SCSI bus during the
Master mode in order to detect which type of device is connected to
the SCSI bus. On power up, the SS7519 will try to deliver LVD
level to the DIFFSENSE line. If only LVD SCSI devices are on the
bus, the DIFFSENSE signal will be successfully driven to 1.3V and the
terminator will configure the system for LVD operation. If any SE
device is on the bus, it will present a grounding level to the
DIFFSENSE line. This will cause the SS7519 to configure into SE
operation. The SS7519 will go into shutdown mode if DIFFSENSE
detects a high voltage level.
DIFFSENSE CAPACITOR. This pin should be connected to a 0.1uF
capacitor to ground and 20KΩ resistor to SCSI bus DIFFSENSE line
for DIFFSEN filter.
RECOMMENDED OPERATING CONDITIONS
PARAMETER
Tpwr Voltage
Operating Temperature
Lead Temperature
(Soldering 10 seconds)
SYMBOL
V_term
T_op
T_sod
MIN
4.0
0
TYP.
300
MAX
5.75
70
UNITS
V
℃
℃
Rev.2.01 6/06/2003
www.SiliconStandard.com
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