DS2129

www.DataSheet4U.com Rev 1; 2/06 LVD SCSI 27-Line Regulator General Description The DS2129 is a triple-output voltage regulator for 27-line, low-voltage-differential (LVD) SCSI termination for SPI-2 and SPI-3 applications using LVD termination networks. The device provides reference voltages and bias currents for LVD-termination resistor pi (π) networks. With a pi network (475Ω , 121 Ω , 475 Ω ), the DS2129 meets the common-mode bias, differential bias, and termination-impedance requirements of SPI-2 (Ultra2) and SPI-3 (Ultra3). The device also provides a 1.3V output for DIFFSENSE signaling, and includes protection features such as thermal shutdown and active current limiting. ♦ 2.7V to 5.25V Operation ♦ Differential Fail-Safe Bias Features ♦ Fully Compliant with SPI-2 and SPI-3 DS2129 Applications SCSI Array Backplane SCSI Cables PART* DS2129S Ordering Information VOLTAGE (V) 5 5 5 5 PINPACKAGE 16 SO 16 SO 16 SO 16 SO TOP MARK** DS2129 DS2129 DS2129 DS2129 Block Diagram DS2129S+ DS2129S/T&R DS2129S+T&R TERMPWR PTAT BANDGAP (1.25V) REF125 THERMAL SHUTDOWN TS +Denotes lead-free package. *All devices rated for the commercial (0°C to +70°C) temperature range. **A “+” anywhere on the topmark denotes a lead-free package. DS2129 REFERENCES REF175 TS 1.75V REG1 Pin Configuration TOP VIEW REF130 TS N.C. 1 TERMPWR 2 0.75V REG2 16 N.C. 15 N.C. 14 HS_GND REG2 3 GND 4 DS2129 13 HS_GND 12 HS_GND 11 HS_GND 10 N.C. 9 N.C. REF075 TS 1.3V DIFFSENSE HS_GND 5 REG1 6 DIFFSEN...