DS2120 Dallas Semiconducotr, DS2120 Datasheet - Page 6

• Manufacturer Part Number: DS2120
• Description: Ultra3 LVD SCSI Terminator
• Manufacturer: Dallas Semiconducotr

Table 1. PIN DESCRIPTION
DS2120E 28-Pin TSSOP
DS2120B 36-Pin SSOP
18–21, 23–26
22–25, 29–32
8–10, 26–28
4–7, 11–16,
2, 3, 33, 35
2–5, 7–12,
27, 28
PIN
6, 22
PIN
13
14
15
16
17
17
18
19
20
21
34
36
1
1
DIFFSENSE
DIFFSENSE
MSTR/SLV
MSTR/SLV
DIFF_CAP
DIFF_CAP
RxP, RxN
RxP, RxN
HS_GND
HS_GND
NAME
NAME
TPWR
TPWR
VREF
VREF
GND
GND
LVD
ISO
ISO
NC
Regulator Output Voltage. 1.25V reference in LVD mode; must be
decoupled with a 4.7µF cap.
Signal Termination. Connect to SCSI bus signal lines.
Heat Sink Ground. Internally connected to the mounting pad. Should be
connected to ground.
Isolation. When pulled high, terminating resistors and biasing current sources
are isolated from the SCSI bus.
Signal Ground.
Master/Slave. Mode select for the noncontrolling terminator. When pulled
high (MSTR), the DIFFSENS driver is enabled.
DIFFSENSE. Output to drive the SCSI bus DIFFSENS line.
DIFFSENSE Capacitor. Connect a 0.1 F capacitor for DIFFSENSE filter.
Input to detect the type of device (differential or single -ended) on the SCSI
bus.
Termination Power. Connect to the SCSI TERMPWR line and decouple with
2.2 F capacitor.
Regulator Output Voltage. 1.25V reference in LVD mode; must be
decoupled with a 4.7µF cap.
No Connect. Do not connect pins.
Signal Termination. Connect to SCSI bus signal lines.
Heat Sink Ground. Internally connected to the mounting pad. Should be
connected to ground.
Isolation. When pulled high, terminating resistors and biasing current sources
are isolated from the SCSI bus.
Signal Ground.
Master/Slave. Mode select for the noncontrolling terminator. When pulled
high (MSTR), the DIFFSENS driver is enabled.
DIFFSENSE. Output to drive the SCSI bus DIFFSENS line.
DIFFSENSE Capacitor. Connect a 0.1 F capacitor for DIFFSENSE filter.
Input to detect the type of device (differential or single ended) on the SCSI
bus.
Low-Voltage Differential. Output of DIFFSENSE receiver; output high
indicates LVD bus operation .
Termination Power. Connect to the SCSI TERMPWR line and decouple with
2.2 F capacitor.
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DESCRIPTION
DESCRIPTION
DS2120