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LIN DOC # : 5225 18-Line SCSI Terminator IMP5225 DESCRIPTION The IMP5225 SCSI terminator is part of IMP's family of high-performance, adaptive, non-linear mode SCSI products, which are designed to deliver true UltraSCSI performance in SCSI applications. The low voltage BiCMOS architecture employed in its design offers superior performance to older linear passive and active techniques. IMP's new architecture employs high-speed adaptive elements for each channel, thereby providing the fastest response possible -- typically 35MHz, which is 100 times faster than the older linear regulator/terminator approach used by other manufacturers. Products using this older linear regulator approach have bandwidths which are dominated by the output capacitor and which are limited to 500KHz (see further discussion in the Functional Description section). The IMP architecture also eliminates the output compensation capacitor required in earlier terminator designs. Each is approved for use with SCSI-1, -2, -3, UltraSCSI and beyond -- providing the highest performance alternative available today. The IMP5225 architecture is much more tolerant of marginal system integrations. A key improvement offered by the IMP5225 lies in its ability to insure reliable, error-free communications even in systems which do not adhere to recommended SCSI hardware design guidelines, such as the use of improper cable lengths and impedances. Frequently, this situation is not controlled by the peripheral or host designer and, when problems occur, they are the first to be made aware of the problem. Quiescent current is typically less than (375A) in this mode, while the output capacitance is also less than 4pF. Reduced component count is also inherent in the IMP5225 architecture. Traditional termination techniques require large stabilization and transient protection capacitors of up to 20F in value and size. The IMP5225 architecture does not require these components, allowing all the cost savings associated with inventory, board space, assembly, reliability, and component costs. The IMP5225 is a superior pin-for-pin replacement for the LX5205, UC5607/5611/ 5617 or the DS2109. KEY FEATURES s ULTRA-FAST RESPONSE FOR FAST-20 SCSI APPLICATIONS s 35MHz CHANNEL BANDWIDTH s 3.5V OPERATION s LESS THAN 4pF OUTPUT CAPACITANCE s SLEEP-MODE CURRENT LESS THAN 275A s THERMALLY SELF LIMITING s NO EXTERNAL COMPENSATION CAPACITORS s COMPATIBLE WITH ACTIVE NEGATION DRIVERS (60mA / CHANNEL) s COMPATIBLE WITH PASSIVE AND ACTIVE TERMINATIONS s APPROVED FOR USE WITH SCSI 1, 2, 3 AND ULTRA SCSI s HOT SWAP COMPATIBLE s PIN-FOR-PIN COMPATIBLE WITH LX5205, UC5607/5611/5617 AND DS2109 PRODUCT HIGHLIGHT R E C E I V I N G WAV E F O R M - 20MH Z D R I V I N G WAV E F O R M - 20MH Z Receiver DISCONNECT 1 DISCONNECT 2 Driver 1 Meter, AWG 28 IMP5225 DISCONNECT 1 DISCONNECT 2 IMP5225 LX5268 or LX5268 PACKAGE ORDER INFORMATION TA (C) 0 to 70 DB Plastic SSOP 28-pin IMP5225CDB DWP Plastic SOWB 28-pin, Power IMP5225CDWP Note: All surface-mount packages are available in Tape & Reel. Append the letter "T" to part number. (i.e. IMP5225CDWPT) 1 ABSOLUTE MAXIMUM RATINGS (Note 1) PACKAGE PIN OUTS 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 ULTRA 18-LINE, PLUG A N D PLAY SCSI TermPwr Voltage ....................................................................................................... +7VTERMINATOR DISCONNECT 1 Signal Line Voltage ........................................................................................... 0V to +7V T1 Regulator Output Current .......................................................................................... 1.2A T2 Operating Junction Temperature T3 T4 Plastic (DB, DWP Packages) ............................................................................... 150C T5 Storage Temperature Range ...................................................................... -65C to 150C H.S./GND Lead Temperature (Soldering, 10 seconds) .............................................................. 300C Note 1. Exceeding these ratings could cause damage to the device. All voltages are with respect to Ground. Currents are positive into, negative out of the specified terminal. THERMAL DATA DB PACKAGE: GND H.S./GND T6 T7 T8 T9 VTERM DISCONNECT 2 T18 T17 T16 T15 T14 H.S./GND H.S./GND H.S./GND T13 T12 T11 T10 N.C. THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA ................... 117C/W DWP PACKAGE: DB PACKAGE (Top View) DISCONNECT 1 T1 T2 T3 T4 T5 HEAT SINK/GND GND HEAT SINK/GND T6 T7 T8 T9 VTERM 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 Junction Temperature Calculation: TJ = TA + (PD x JA). The JA numbers are guidelines for the thermal performance of the device/pc-board system. All of the above assume no ambient airflow. THERMAL RESISTANCE-JUNCTION TO LEADS, JL ............................ 18C/W THERMAL RESISTANCE-JUNCTION TO AMBIENT, JA ..................... 40C/W DISCONNECT 2 T18 T17 T16 T15 T14 HEAT SINK/GND HEAT SINK/GND HEAT SINK/GND T13 T12 T11 T10 N.C. DWP PACKAGE (Top View) RECOMMENDED OPERATING CONDITIONS (Note 2) Parameter Termpwr Voltage Signal Line Voltage Disconnect Input Voltage Operating Virtual Junction Temperature Range IMP5225C Note 2. Range over which the device is functional. Symbol VTERM Recommended Operating Conditions Min. Typ. Max. 3.3 0 0 0 5.5 5 VTERM 125 Units V V V C ELECTRICAL CHARACTERISTICS Term Power = 4.75V unless otherwise specified. Unless otherwise specified, these specifications apply at the recommended operating ambient temperature of TA = 25C. Low duty cycle pulse testing techniques are used which maintains junction and case temperatures equal to the ambient temperature. Parameter Output High Voltage TermPwr Supply Current Symbol VOUT ICC Test Conditions All data lines = open All data lines = 0.5V DISCONNECT Pins < 0.8V or > 2.0V VOUT = 0.5V DISCONNECT Pins = 4.75V DISCONNECT Pins = 0V DISCONNECT Pins = < 0.8V, VO = 0.5V VOUT = 0V, frequency = 1MHz VOUT = 4V Min. 2.65 10 LX5225 Typ. 2.85 400 200 -23 10 -90 10 3 35 60 Max. 18 450 -24 Units V mA mA A mA nA A nA pF MHz mA Output Current DISCONNECT Input Current Output Leakage Current Capacitance in DISCONNECT Mode Channel Bandwidth Termination Sink Current, per Channel IOUT IIN IOL COUT BW ISINK -21 2 FUNCTIONAL DESCRIPTION ULTRA 18-LINE, PLUG PLAY SCSI device is in a sleep state where a meager 200A Cable transmission theory suggests to optimize signal speed and A N Ddisable mode, theTERMINATOR of quiescent current is consumed. Additionally, all outputs are in quality, the termination should act both as an ideal voltage a Hi-Z (impedance) state. Sleep mode can be used for power reference when the line is released (deasserted) and as an ideal conservation or to completely eliminate the terminator from the current source when the line is active (asserted). Common active SCSI chain. In the second terminators, which consist POWER UP / POWER DOWN FUNCTION TABLE case, termination node of Linear Regulators in capacitance is important to series with resistors Quiescent DISCONNECT 1 DISCONNECT 2 Outputs consider. The terminator (typically 110), are a Current will appear as a parasitic compromise. As the line distributed capacitance on voltage increases, the H H Disabled 200A the line, which can detract amount of current H L Enabled 10mA from bus performance. For decreases linearly by the L H Disabled 200A this reason, the IMP5225 equation V = I * R. The L L Disabled 200A has been optimized to have IMP5225, with its unique only 4pF of capacitance per new architecture applies Open Open Disabled 200A output in the sleep state. the maximum amount of An additional feature of the IMP5225 is its compatibility with current regardless of line voltage until the termination high active negation drivers. The device handles up to 60mA of sink threshold (2.85V) is reached. current for drivers which exceed the 2.85V output high. Acting as a near ideal line terminator, the IMP5225 closely reproduces the optimum case when the device is enabled. In the BLOCK DIAGRAM FIGURE 1 -- IMP5225 BLOCK DIAGRAM TERM POWER THERMAL LIMITING CIRCUIT CURRENT BIASING CIRCUIT 24mA CURRENT LIMITING CIRCUIT DATA OUTPUT PIN DB(0) VTERM 2.85V DISC1 DISCONNECT 1 DISCONNECT 2 DISC2 ENABLE LOGIC .4V VTERM 1 OF 18 CHANNELS APPLICATION SCHEMATIC FIGURE 2 -- 8-BIT SCSI SYSTEM APPLICATION 5V 4.7F TERM POWER VTERM HOST PERIPHERAL TERM POWER VTERM 4.7F 5V DISCONNECT ~~~ IMP5225 ACK RST MSG ACK RST MSG IMP5225 SCSI CABLE 3 DISCONNECT DB (0) DB (1) ~~ DB (0) DB (1) PACKAGE DIMENSIONS ULTRA 18-LINE, PLUG AND PLAY SCSI TERMINATOR DIM A B C D F G J K L M P MILLIMETERS MIN MAX 17.73 17.93 7.40 7.60 2.44 2.64 0.36 0.46 0.51 1.01 1.27 BSC 0.123 0.32 0.10 0.30 8.13 8.64 0 8 10.26 10.65 INCHES MIN MAX 0.698 0.705 0.291 0.299 0.096 0.104 0.014 0.018 0.020 0.040 0.050 BSC 0.005 0.013 0.004 0.012 0.320 0.390 0 8 0.404 0.419 DWP 28-Pin Plastic SOWB POWER 28 1 A 15 B 14 P F G D L C M SEATING PLANE K J DB 28-Pin Shrink Small Outline Package (SSOP) EP 123 D F AH E SEATING PLANE B G L C M DIM A B C D E F G H L M P MILLIMETERS MIN MAX 1.73 1.99 0.25 0.38 0.13 0.22 10.07 10.33 5.20 5.38 0.65 BSC 0.05 0.21 1.63 1.83 0.65 0.95 0 8 7.65 7.90 INCHES MIN MAX 0.068 0.078 0.009 0.015 0.005 0.008 0.396 0.407 0.205 0.212 0.025 BSC 0.002 0.008 0.064 0.072 0.025 0.037 0 8 0.301 0.311 IMP, Inc. Corporate Headquarters 2830 N. First Street San Jose, CA 95134 Tel: 408.432.9100 Main Tel: 800.438.3722 Fax: 408.434.0335 Fax-on-Demand: 800.249.1614 (USA) Fax-on-Demand: 303.575.6156 (International) e-mail: info@impinc.com http://www.impweb.com The IMP logo is a registered trademark of IMP, Inc. All other company and product names are trademarks of their respective owners. (c) 1998 IMP, Inc. Printed in USA Part No.: IMP5225 Document Number: IMP5225-04-4/98 4 |
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