Maker : ETC
Part No. : G219

  Datasheet PDF : G219.pdf
  Cross Reference : G219 Cross Reference
  Buy Component : G219 Find Stock and Price

Shortcut : G2113  G2119  G2123  G219  G219R-D3  G219T-D3 

Product Information

Global Mixed-mode Technology Inc. G219 Ultra320 Multi-mode LVD/SE SCSI Terminator Features Auto-selectable multi-mode Single-Ended or LVD Termination Meets SCSI-1, SCSI-2, SCSI-3 SPI Ultra (Fast-20), Ultra 2(SPI-2 LVD), Ultra160 (SPI-3 LVD), and Ultra320 (SPI-4 LVD) standards Supports active negation 3pF channel capacitance 2.9V to 5.5V operation Thermal protection Hot-Swap compatible 5% tolerance on SE and LVD termination resistance 28 pin TSSOP package 28 Pin TSSOP: Pin Compatible with DS2119 General Description The G219 Multi-mode LVD/SE SCSI terminator provides a smooth transition into the next generation of the SCSI Parallel Interface (SPI-4). It automatically senses the bus, via DIFFSENS, and switches the termination to either single-ended (SE) or low voltage differential (LVD) SCSI, dependent on which type of devices are connected to the bus. If the G219 detects a HVD SCSI device, it switches to a high impedance state. For a 16-bit Wide SCSI bus to be operational, three G219 terminators are needed. The Multi-mode terminator contains all functions required 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 G219 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 G219 VREF R1+ R1R2+ R2NC/ HS GND R3+ R3R4+ R4R5+ R5DISCNCT GND 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 TPWR TPWR R9R9+ R8R8+ NC/ HS GND R7R7+ R6R6+ DIFFB DIFFSENSE M/S 28Pin TSSOP Ver 1.2 Feb 08, 2002 TEL: 886-3-5788833 http://www.gmt.com.tw 1 Global Mixed-mode Technology Inc. Ordering Information PART NUMBER G219T-D3 G219R-D3 G219 PIN-PACKAGE TSSOP-28 pin / Tube TSSOP-28 pin / Tape & Reel TEMP. RANGE 0ºC-70ºC 0ºC-70ºC Note: DIFFSENSRefers to the SCSI bus signal. DIFFSENSERefers to the G219 pin name and internal circuitry relating to differential sensing. DIFFBRefers to the G219 pin name and internal circuitry relating to monitoring the DIFFSENS line. Functional Description The G219 is used in multi-mode active termination applications, where single ended (SE) and low voltage differential (LVD) devices might coexist. The LVD termination section consists of 18 source/sink amplifiers (VTOP, VBOT), biasing circuitry and nine precision resistor strings (RTOP, RMID, RBOT). The SE termination section consists of a 2.85V source/sink regulator with 9 precision 110ohm resistor. The DIFFSENSE section consists of a 1.3V, 5mA driver and a sensing circuit (Figure 1) DIFFSENS is used to identify which types of SCSI devices are present on the bus. If the voltage on DIFFSENS is between 0-0.5V the bus is single-ended; if it is between 0.7-1.9V the bus is LVD; and if it is greater than 2.4V, the bus is HVD. The G219 DIFFB pin monitors the DIFFSENS line to determine the proper operating mode of the device. HVD Isolation Mode The G219 identifies that there is an HVD (high voltage differential) device on the SCSI bus and isolates the termination pins from the bus. When DISCNCT is pulled high, the termination pins are isolated from the SCSI bus, and VREF is grounded. During thermal shutdown, the termination pins are isolated from the SCSI bus and VREF is grounded. The DIFFSENSE driver is shut down during either of these two events. To ensure proper operation, the TPWR pin should be connected to the SCSI bus TERMPWR line. As with all analog circuitry, the TERMPWR lines should be bypassed locally. A 2.2µF capacitor and a 0.01µF high frequency capacitor is recommended between TPWR and ground and placed as close as possible to the G219. The G219 should be placed as close as possible to the SCSI connector to minimize signal and power trace length, thereby resulting in less input ca- pacitance and reflections which can degrade the bus signals...

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