SN75971B2DL

SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 D D D D D D D D D Provides High-Voltage Differential SCSI From Single-Ended Controller When Used With the SN75970B Control Transceiver Meets or Exceeds the Requirements of EIA Standard RS-485 and ISO-8482 Standards ESD Protection on Bus Pins to 12 kV Packaged in Shrink Small-Outline Package with 25 mil Terminal Pitch and Thin Small-Package with 20 mil Terminal Pitch Low Disabled-Supply Current 32 mA Typ Thermal Shutdown Protection Positive- and Negative-Current Limiting Power-Up/-Down Glitch Protection Open-Circuit Failsafe Receivers DGG OR DL PACKAGE (TOP VIEW) description The SN75971B SCSI differential converter-data is a 9-channel RS-485 transceiver. When used in conjunction with its companion control transceiver, the SN75970B, the resulting chip set provides the superior electrical performance of differential SCSI from a single-ended SCSI bus or controller. A 16-bit Ultra-SCSI (or Fast-20) SCSI bus can be implemented with just three devices (two data and one control) in the space efficient, 56-pin, shrink small-outline package (SSOP) or thin shink small outline package (TSSOP) and a few external components. An 8-bit SCSI bus requires only one data and one control transceiver. The SN75971B is available in a B2 (20 Mxfer) version and a B1 (10 Mxfer) version. SDB DRVBUS GND ADBP – NC ADB7 – NC ADB6 – NC ADB5 – NC VCC GND GND GND GND GND VCC ABD4 – NC ADB3 – NC ADB2 – NC ADB1 – NC ADB0 – NC 1 56 2 55 3 54 4 53 5 52 6 51 7 50 8 49 9 48 10 47 11 46 12 45 13 44 14 43 15 42 16 41 17 40 18 39 19 38 20 37 21 36 22 35 23 34 24 33 25 32 26 31 27 30 28 29 DSENS RESET GND BDBP – BDBP + BDB7 – BDB7 + BDB6 – BDB6 + BDB5 – BDB5 + VCC GND GND GND GND GND VCC BDB4 – BDB4 + BDB3 – BDB3 + BDB2 – BDB2 + BDB1 – BDB1 + BDB0 – BDB0 + Pins 13 – 17 and 40 – 44 are connected together to the package lead frame and In a typical differential SCSI node, the SCSI controller to signal ground. provides an enable for each external RS-485 NC – No internal connection transceiver channel. This could require as many as 27 extra terminals for a 16-bit differential bus controller or relegate a 16-bit, single-ended controller to only an 8-bit differential bus. Using the standard nine SCSIcontrol signals, the SN75970B control transceiver decodes the state of the bus and enables the SN75971B data transceiver to transmit the single-ended SCSI input signals (A side) differentially to the cable or receive the differential cable signals (B side) and drive the single-ended outputs to the controller. A reset function, which disables all outputs and clears internal latches, can be accomplished from two external inputs and two internally-generated signals. RESET (reset) and DSENS (differential sense) are available to external circuits for a bus reset or to disable all outputs should a single-ended cable be inadvertently connected to a differential connector. Internally-generated power-up and thermal-shutdown signals have the same affect when the supply voltage is below approximately 3.5 V or the junction temperature exceeds 175°C. Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet. Copyright  2000, Texas Instruments Incorporated PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 1 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 description (continued) The SCSI, differential, converter-data chip operates in two modes depending on the state of the DRVBUS input. With DRVBUS low, a bidirectional latch circuit sets the direction of data transfer. Each data bit has its own latch, and each bit’s direction is independent of all other bits. When neither the single-ended nor the differential sides are asserted, the latch disables both A- and B-side output drivers. When the input to either side is asserted, the latch enables the opposite side’s driver and sets data flow from the asserted input to the opposite side of the device. When the input deasserts, the latch maintains the direction until the receiver on the enabled driver detects a deassertion. The latch then returns to the initial state. No parity checking is done by this device; the parity signal passes through the device like other data signals do. When DRVBUS is high, direction is determined by the SDB signal. However, a change in SDB does not always immediately change the direction. When DRVBUS first asserts, the direction indicated by SDB is latched and takes effect immediately. When SDB changes while DRVBUS is high, the drivers that were on immediately turn off. However, the other driver set does not turn on until the receivers sense a deasserted state on all nine data lines. This is done to prevent the active drivers from turning on until all other drivers are off and the terminators pull the lines to a deasserted state. The single-ended SCSI bus interface consists of CMOS, bidirectional inputs and outputs. The drivers are rated to ± 16 mA of output current. The receiver inputs are pulled high with approximately 4 mA to eliminate the need for external pullup resistors for the open-drain outputs of most single-ended SCSI controllers. The single-ended side of the device is not intended to drive the SCSI bus directly. The differential SCSI bus interface consists of bipolar, bidirectional inputs and outputs that meet or exceed the requirements of EIA-485 and ISO 8482-1982/TIA TR30.2 referenced by American National Standard of Information Systems (ANSI) X3.131-1994 Small Computer System Interface-2 (SCSI-2) and SCSI-3 Fast-20 Parallel Interface (Fast-20) X3.277:1996. The SN75971B is characterized for operation over the temperature range of 0°C to 70°C. Terminal Functions TERMINAL I/O DESCRIPTION 4, 6, 8, 10, 19, 21, 23, 25, 27 I/O, Single-ended SCSI voltage levels, Strong pullup Bidirectional I/O for data and parity bits to and from the single-ended SCSI controller. As outputs, these terminals can source or sink 16 mA. As inputs, they are pulled up with about 4-mA to eliminate external resistors. BDBn+, where n = {0,1,2,3,4,5,6,7,P} 29, 31, 33, 35, 37, 46, 48, 50, 52 I/O, RS-485, Weak pulldown Bidirectional I/O for data and parity to and from the differential SCSI bus. BDBn–, where n = {0,1,2,3,4,5,6,7,P} 30, 32, 34, 36, 38,47, 49, 51, 53 I/O, RS-485, Weak pulldown Bidirectional I/O for the complement of data and parity to and from the differential SCSI bus. DRVBUS 2 Input, TTL levels, Weak pulldown A high-level logic signal from the control transceiver enables either the single-ended or differential drivers as directed by SDB. DSENS 56 Input, TTL levels, Weak pullup A low-level input initializes the internal latches and disables all drivers. RESET 55 Input, TTL levels, Weak pullup A low-level input initializes the internal latches and disables all drivers. SDB 1 Input, TTL levels, Weak pulldown A high-level logic signal from the control transceiver sends data from the differential bus to the single-ended bus. A low-level signal reverses the flow. NAME NO. ADBn–, where n = {0,1,2,3,4,5,6,7,P} 2 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 functional block diagram SN75971B 53 ADBP – 4 52 Control Latch ADB7 – BDBP – BDBP + 51 BDB7 – 50 BDB7 + 6 Control Latch (6 Identical Channels Not Shown) 30 ADB0 – 27 29 Control Latch Power-Up and Thermal Shut-Down Circuits BDB0 – BDB0 + Steering and Control Logic 2 1 55 56 DRVBUS RESET DSENS SDB POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 schematics of inputs and outputs RESET, AND DSENS SDB AND DRVBUS VCC VCC 22 kΩ 200 Ω 200 Ω Input Input 50 kΩ B + AND B – Inputs A VCC VCC 4 mA 100 kΩ (B – Pin Only) 3 kΩ Input Input 200 Ω 18 kΩ 100 kΩ (B + Pin Only) 12 kΩ 1 kΩ B + AND B – Outputs A VCC VCC B– Output 18 kΩ Output B+ 4 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 absolute maximum ratings over operating free-air temperature range (unless otherwise noted)† Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.3 V to 7 V Differential bus voltage range (B side) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –10 V to 15 V Single-ended bus voltage range (A side and control inputs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.3 V to 7 V Continuous total power dissipation (see Note 2) . . . . . . . . . . Internally Limited (see Dissipation Rating Table) Electrostatic discharge (see Note 3): Class 2 A (all pins) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 kV Class 2 B (all pins) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 V Class 3 A (B-side and GND) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 kV Class 3 B (B-side and GND) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400 V Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65°C to 150°C Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260°C † Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. NOTES: 1. All voltage values are with respect to GND. 2. The maximum operating junction temperature is internally limited. Use the dissipation rating table to operate below this temperature. 3. This absolute maximum rating is tested in accordance with MIL-STD-883C, Method 3015.7. DISSIPATION RATING TABLE TA ≤ 25°C POWER RATING DGG 3333 mW DERATING FACTOR‡ ABOVE TA = 25°C 26.7 mW/°C DL 3709 mW 29.7 mW/°C PACKAGE TA = 70°C POWER RATING 2133 mW 2374 mW ‡ This is the inverse of the traditional junction-to-case thermal resistance (RθJA) for High-K (per JEDEC) PCB installations. recommended operating conditions Supply voltage, VCC MIN NOM MAX UNIT 4.75 5 5.25 V High-level input voltage, VIH A side and control Low-level input voltage, VIL A side and control 2 0.8 V V Voltage at any bus terminal (separately or common-mode), VO or VI B side 12 –7 V High-level output current, IOH A side – 16 mA Low-level output current, IOL A side 16 mA Operating case temperature, TC 0 125 °C Operating free-air temperature, TA 0 70 °C POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 5 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 electrical characteristics over recommended operating conditions (unless otherwise noted) PARAMETER VOD(H) VOD(L) See Figure 1 Driver low-level differential output voltage See Figure 1 VOH High-level g output voltage VOL Low level output voltage Low-level VIT+ Receiver positive-going differential input threshold voltage VIT– Receiver negative-going differential input threshold voltage Vhys Receiver input hysteresis voltage (VIT + – VIT –) II TEST CONDITIONS Driver high-level differential output voltage Bus input current A side B side A side B side B side VID = – 200 mV, IOH = – 60 mA IOH = – 16 mA VID = 200 mV, IOL = 60 mA IOL = 16 mA IOH = – 16 mA See Figure 2 IOL = 16 mA See Figure 2 High-level input current V 1 1.8 V 2.5 4.2 0.4 0.2 – 0.2§ 45 1 0.7 1 VI = – 7 V, V Other input at 0 V VCC = 5 V VCC = 0 – 0.5 – 0.8 – 0.4 – 0.8 –5 –8 – 70 – 100 VIH = 2 V RESET, DSENS 25 VIL = 0.8 V –6 –9 – 66 – 100 ± 30 SDB, DRVBUS IOS Short-circuit output current IOZ High-impedance-state Hi hi d t t out ut current output B side ± 250 VO = 5 V and 0 –2 A side B side ICC Supply current –5 –8 –6 –9 Disabled RESET at 0.8 V, Others open 38 46 SDB and DRVBUS at 2 V, All other inputs open, VID = – 1 V, No load 39 50 A to B Enabled SDB at 0.8 V, All other inputs open, DRVBUS at 2 V, No load 32 66 VI = 0.6 sin(2π × 106t) + 1.5 V, B to A, BDBn to GND 18 21 One channel 40 A to B, One channel 100 Output capacitance Cpd d Power dissipation capacitance‡ mA mA mA µA mA µA mA See II B to A Enabled CO V mV 0.6 –2 V V VCC = 5 V VCC = 0 A side Low-level input current 0.8 1.6 SDB, DRVBUS IIL V V Other input at 0 V VI = 12 V, B or B UNIT –2.2 35 RESET, DSENS MAX –1 3.4 A side IIH MIN TYP† mA pF pF pF † All typical values are at VCC = 5 V, TA = 25°C. ‡ Cpd determines the no-load dynamic current consumption, IS = Cpd × VCC × f + ICC. § The algebraic convention with the least positive (more negative) limit is designated minimum, is used in this data sheet for the differential input voltage only. 6 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 switching characteristics over recommended of operating conditions (unless otherwise noted) PARAMETER TEST CONDITIONS See Figures 3 and 4 SN75971B1 td1, td2 Delayy time,, A to B,, highg to lowlevel or low- to high-level output VCC = 5 V, VCC = 5 V, TA = 25°C, TA = 70°C, VCC = 5 V, VCC = 5 V, TA = 25°C, TA = 70°C, td3, td4 Delayy time,, B to A,, highg to lowlevel or low- to high-level output 4 12 4.9 12.9 5 12 See Figures 3 and 4 6.2 10.2 See Figures 3 and 4 6.9 10.9 5.4 18.1 SN75971B1 Skew part-to-part Skew, part to part† SN75971B2 tsk(p) Pulse skew‡ tdis1 tdis2 Disable time, A to B Disable time, B to A ten1 ten2 TA = 25°C, TA = 70°C, See Figures 5 and 6 6.5 15.4 See Figures 5 and 6 7.2 16.1 7.7 15 See Figures 5 and 6 8.7 13.2 See Figures 5 and 6 9.4 13.9 See Figures 5 and 6 SN75971B2 tsk(pp) k( ) VCC = 5 V, VCC = 5 V, 14 See Figures 3 and 4 See Figures 5 and 6 SN75971B1 MAX 3 See Figures 3 and 4 See Figures 3 and 4 SN75971B2 MIN VCC = 5 V, VCC = 5 V, TA = 25°C, TA = 70°C, A to B See Figures 5 and 6 8 B to A See Figures 5 and 6 9 A to B See Figures 5 and 6 4 B to A See Figures 5 and 6 5 UNIT ns ns ns 4 ns See Figures 3 and 4 200 ns See Figures 5 and 6 35 ns Enable time, A to B See Figures 3 and 4 65 ns Enable time, B to A See Figures 5 and 6 65 ns ten(TX) Enable time, receive-to-transmit See Figure 7 142 ns † Part-to-part skew is the magnitude of the difference in propagation delay times between any two devices when both operate with the same supply voltages, the same temperature, and the same loads. ‡ Pulse skew is the difference between the high-to-low and low-to-high propagation delay times of any single channel. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 7 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 PARAMETER MEASUREMENT INFORMATION 5V 165 Ω BDBn– 2 V or 0.8 V ADBn – VOD 75 Ω VOH, VOL VIH, VIL BDBn + 165 Ω VOH, VOL NOTES: A. Resistance values are in ohms with a tolerance of ± 5%. B. All input voltage levels are held to within 0.01 V. C. The logical function is set with SDB at 0.8 V, DRVBUS at 3.5 V, and all others left open. Figure 1. Differential Driver VOD, VOH, and VOL Test Circuit BDBn – II VI ADBn – VID or VIT BDBn + IOH or IOL VOL or VOL NOTES: A. Resistance values are in ohms with a tolerance of ± 5%. B. All input voltage levels are held to within 0.01 V. C. The logical function is set with SDB and DRVBUS at 3.5 V, and all others left open. Figure 2. Single-Ended Driver VOH, VOL, VIT +, and VIT – Test Circuit 8 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 PARAMETER MEASUREMENT INFORMATION GND A S1 B+ IO 15 pF II A Input (see Note A) 165 Ω B 165 Ω 375 Ω VO VI 375 Ω 75 Ω VOD IO B– VO S2 15 pF 5V 0.5 V Input Output VOD(H) ~ – 0.925 V VOD(L) 3V 1.5 V 0V t0 or t0 50% ten td td tdis NOTES: A. The input pulse is supplied by a generator having the following characteristics: PRR ≤ 1 MHz, 45% < duty cycle < 50%, tr ≤ 1 ns, tf ≤ 1 ns, ZO = 50 Ω. B. CL includes probe and jig capacitance. C. Resistance values are in ohms with a tolerance of ± 5%. D. All input voltage levels are held to within 0.01 V. Figure 3. A to B Propagation Delay Time Test Circuit SDB DSENS RESET ADBn – DRVBUS td1 td2 ten1 tdis1 BDBn – BDBn + VOD Figure 4. A to B Timing Waveforms POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 9 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 PARAMETER MEASUREMENT INFORMATION BDBn – 1.5 V BDBn + Input (see Note A) ADBn – Output 15 pF (see Note B) 0.5 V Input Output VOH ~ 2.5 V 1.5 V 3V 1.5 V 0V t0 or t0 VOL ten td td tdis NOTES: A. The input pulse is supplied by a generator having the following characteristics: PRR ≤ 1 MHz, 45% < duty cycle < 50%, tr ≤ 1 ns, tf ≤ 1 ns, ZO = 50 Ω. B. CL includes probe and jig capacitance. C. Resistance values are in ohms with a tolerance of ± 5%. D. All input voltage levels are held to within 0.01 V. Figure 5. B to A Propagation Delay Time Test Circuit SDB DSENS RESET BDBn – DRVBUS td3 td4 ten2 ADBn – Figure 6. B to A Timing Waveforms 10 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 tdis2 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 PARAMETER MEASUREMENT INFORMATION RESET DRVBUS BDB0 + BDB0 – ADB0 – SDB BDB1,2,3,4,5,7 + ADB1,2,3,4,5,7– and BDB1,2,3,4,5,7 – ADB6 – BDB6 + BDB6 – ten(TX) Output Output VOH 1.5 V 0V BDB0 – Input ten(TX) Input ≈3 V 1.5 V BDB6 – Output VOL Figure 7. Receive-to-Transmit (ten(TX)) Timing Waveforms POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 11 SN75971B SCSI DIFFERENTIAL CONVERTER-DATA SLLS322A – NOVEMBER 1999 – REVISED JANUARY 2000 APPLICATION INFORMATION SN75970B DIFFSENS ± BSY ± SEL ± RST ± I/O ± MSG ± C/D ± REQ ± ATN ± ACK 6 8 – BSY, – SEL, – I/O, – MSG, – C/D, – REQ, – ATN, – ACK 8 – RST 20 kΩ 4 TEST RSTFLTR 0.1 µF CLK 40 (see Note A) RESET RESET (from system) X1/CLK20 20 MHz (see Note A) Optional (see Note B) X2 SCSI Controller VCC 0.022 µF TIMEOUT DRVBUS ± DB(7 – 0) ± DBP(0) 16 SN75971B ADBn BDBn BDBP ADBP– DSENS RESET DRVBUS ± DBP(1) DIFFSENS 8 2 DIFFSENS ± DB(15 – 8) 205 kΩ SDB 16 2 – DB(7 – 0) – DBP(0) RESET SDB SN75971B BDBn ADBn BDBP ADBP– DSENS RESET 8 – DB(15 – 8) – DBP(1) RESET NOTES: A. When using the 40-MHz clock input, X1 must be connected to VCC. B. The oscillator cell of the SN75970B is for a series-resonant crystal and requires approximately 10 pF (including fixture capacitance) from X1 and X2 to ground in order to function. Figure 8. Typical Application of the SN75970B and SN75971B 12 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 PACKAGE OPTION ADDENDUM www.ti.com 10-Dec-2020 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (°C) Device Marking (3) (4/5) (6) SN75971B2DL ACTIVE SSOP DL 56 20 RoHS & Green NIPDAU Level-2-260C-1 YEAR 0 to 70 SN75971B2 (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of