SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 D D D D D D D D D Nine Differential Channels for the Data and Control Paths of the Differential Small Computer Systems Interface (SCSI) Meets or Exceeds the Requirements of ANSI Standard RS-485 and ISO 8482:1987(E) Packaged in Shrink Small-Outline Package With 25-mil Terminal Pitch Designed to Operate at 10 Million Transfers Per Second Low Disabled Supply Current 1.4 mA Typ Thermal Shutdown Protection Power-Up/Power-Down Glitch Protection Positive and Negative Output-Current Limiting Open-Circuit Fail-Safe Receiver Design DL PACKAGE (TOP VIEW) NC WRAP2 WRAP1 1A 1DE/RE 2A 2DE/RE 3A 3DE/RE 4A 4DE/RE VCC GND GND GND GND GND VCC 5A 5DE/RE 6A 6DE/RE 7A 7DE/RE 8A 8DE/RE 9A 9DE/RE description The SN75LBC978 is a nine-channel differential transceiver based on the 75LBC176 LinASIC cell. Use of TI’s LinBiCMOS† process technology allows the power reduction necessary to integrate nine differential balanced transceivers†. On-chip enabling logic makes this device applicable for the data path (eight data bits plus parity) and the control path (nine bits) for the Small Computer Systems Interface (SCSI) standard. The WRAP function allows in-circuit testing and wired-OR channels for the BSY, RST, and SEL signals of the SCSI bus. 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 NC NC CE 9B + 9B – 8B + 8B – 7B + 7B – 6B + 6B – VCC GND GND GND GND GND VCC 5B + 5B – 4B + 4B – 3B + 3B – 2B + 2B – 1B + 1B – Pins 13 through 17 and 40 through 44 are connected together to the package lead frame and signal ground. The SN75LBC978 is packaged in a shrink small-outline package (DL) with improved thermal characteristics using heat-sink terminals. This package is ideal for low-profile, space-restricted applications such as hard disk drives. The switching speed of the SN75LBC978 is sufficient to transfer data over the data bus at 10 million transfers per second. Each of the nine identical channels conforms to the requirements of the ANSI RS-485 and ISO 8482:1987(E) standards referenced by ANSI X3.131-1993 (SCSI-2) and the proposed SCSI-3 standards. The SN75LBC978 is characterized for operation from 0°C to 70°C. † Patent Pending LinASIC and LinBiCMOS are trademarks of Texas Instruments Incorporated. Copyright 1997, 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 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 logic diagram (positive logic) 1A WRAP1 1DE/RE CE 2A 2DE/RE 3A 3DE/RE 4A 4DE/RE 5A 5DE/RE 6A 4 30 3 29 54 6 7 32 Channel 2 8 9 34 Channel 3 Channel 4 35 38 19 20 33 36 10 11 31 Channel 5 37 47 21 Channel 6 46 23 49 2 48 WRAP2 7DE/RE 8A 8DE/RE 9A 9DE/RE 2 1B – 5 6DE/RE 22 7A 1B+ 2B+ 2B – 3B+ 3B – 4B+ 4B – 5B+ 5B – 6B+ 6B – 7B+ 7B – 24 51 25 26 50 Channel 9 53 9B+ 52 9B – 27 28 8B+ Channel 8 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 8B – SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 schematics of inputs and outputs ALL INPUTS EXCEPT CE INPUT CE VCC VCC 22 kΩ 300 Ω 300 Ω Input Input 50 kΩ B+ AND B – I/O PORTS RECEIVER OUTPUT VCC VCC 100 kΩ B+ Only 3 kΩ 18 kΩ Receiver Driver A Output 100 kΩ B – Only 12 kΩ 1 kΩ B+ or B – 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 Bus voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 10 V to 15 V Data I/O and control (A-side) voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 0.3 V to 7 V Continuous power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . internally limited 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. NOTE 1: All voltage values are dc and with respect to GND. POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 3 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 recommended operating conditions Supply voltage, VCC MIN NOM MAX UNIT 4.75 5 5.25 V 12 mode) VO, VI, or VIC Voltage at any bus terminal (separately or common common-mode), B + or B – High-level input voltage, VIH All except B + and B – Low-level input voltage, VIL All except B + and B – –7 2 V 0.8 V – 60 mA A –8 mA B + or B – 60 mA 8 mA 70 °C B + or B – High level output current, High-level current IOH Low level output current, Low-level current IOL V A Operating free-air temperature, TA 0 device electrical characteristics over recommended ranges of operating conditions PARAMETER IIH IIL ICC CO Cpd d High level input current High-level Low level input current Low-level Supply current TEST CONDITIONS A, WRAP, DE/RE CE A, WRAP, DE/RE All receivers enabled No load, CE at 5 V, VID = 5 V, WRAP and DE/RE at 0 V All drivers enabled No load, WRAP at 0 V CE and DE/RE at 5 V, UNIT µA 100 µA µA 100 µA 1.4 3 mA 29 45 mA 7 10 mA VIL = 0 0.8 8V CE at 0 V MAX – 200 – 200 See Figure 1 All drivers and receivers disabled Power dissipation capacitance TYP† VIH = 2 V CE Bus port output capacitance MIN B + or B – 19 pF One driver 460 pF 40 pF One receiver driver electrical characteristics over recommended ranges of operating conditions (unless otherwise noted) PARAMETER | VOD | Differential output voltage IOS IOZ Output short-circuit current 4 TEST CONDITIONS Vtest = – 7 V to 12 V, See Figure 3 High-impedance-state output current MIN TYP 1 2 See Figure 2 See receiver input current POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 MAX UNIT V ± 250 mA SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 receiver electrical characteristics over recommended ranges of operating conditions (unless otherwise noted) (see Figure 3) PARAMETER TEST CONDITIONS VOH VOL High-level output voltage VIT+ VIT– Differential-input high-level threshold voltage Vhys Receiver input hysteresis voltage ( VIT+ – VIT– ) II IOZ VID = 200 mV, VID = – 200 mV, Low-level output voltage Differential-input low-level threshold voltage Receiver input current B+ and B – High impedance state output current High-impedance-state IOH = – 8 mA IOL = 8 mA IOH = – 8 mA IOL = 8 mA MIN TYP† MAX 2.5 UNIT V 0.8 V 0.2 V – 0.2 V 45 mV VI = 12 V, Other input at 0 V VCC = 5 V, 0.7 1 mA VI = 12 V, Other input at 0 V VCC = 0 V, 0.8 1 mA VI = – 7 V, Other input at 0 V VCC = 5 V, – 0.5 – 0.8 mA VI = – 7 V, Other input at 0 V VCC = 0 V, – 0.4 – 0.8 mA VO = GND VO = VCC – 200 50 µA driver switching characteristics over recommended ranges of operating conditions (unless otherwise noted) PARAMETER TEST CONDITIONS See Figure 4 td(OD) ( ) tsk(lim) k(li ) tsk(p) tt Differential delay time, high- to low-level output (td(ODH)) or lowto high-level output out ut (td(ODL)) Skew limit,, the maximum difference in propagation g delay y times between any two drivers on any two devices Pulse skew (|td(ODL) – td(ODH)|) MIN 11.8 VCC = 5 V, See Figure 4 TA = 25°C, VCC = 5 V, See Figure 4 TA = 70°C, VCC = 5 V, See Note 2 MAX UNIT 26.4 14 18 22 18 22 26 15 8 0 See Figure 4 Transition time (tr or tf) TYP† 6 10 ns ns ns ns receiver switching characteristics over recommended ranges of operating conditions (unless otherwise noted) PARAMETER TEST CONDITIONS See Figure 5 tpd Propagation delay time, high- to low-level output (tPHL) or low- to high-level out ut (tPLH) output tsk(lim) k(li ) Skew limit,, the maximum difference in propagation g delay y times between any two drivers on any two devices tsk(p) Pulse skew ( |tPHL – tPLH| ) TYP† 19.5 VCC = 5 V, See Figure 5 TA = 25°C, VCC = 5 V, See Figure 5 TA = 70°C, VCC = 5 V, See Note 2 MAX tt Transition time ( tr or tf ) † All typical values are at VCC = 5 V, TA = 25°C. ‡ Cpd determines the no-load dynamic current consumption; IS = Cpd ⋅ VCC ⋅ f + ICC. NOTE 2: This specification applies to any 5°C band within the operating temperature range. • DALLAS, TEXAS 75265 UNIT 30.7 20.2 24.7 29.2 21.1 25.6 30.1 12 See Figure 5 POST OFFICE BOX 655303 MIN 9 2 3 6 ns ns ns ns 5 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 transceiver switching characteristics over recommended ranges of operating conditions PARAMETER TEST CONDITIONS ten(TXL) ten(TXH) Enable time, transmit-to-receive to low-level output ten(RXL) ten(RXH) Enable time, receive-to-transmit to low-level output tsu Setup time, WRAP1 or WRAP2 before active input(s) or output(s) MIN Enable time, transmit-to-receive to high-level output See Figure 6 Enable time, receive-to-transmit to high-level output MAX UNIT 80 ns 80 ns 150 ns 150 ns 150 ns thermal characteristics PARAMETER TEST CONDITIONS RθJA Junction-to-free-air thermal resistance RθJC Junction-to-case thermal resistance MIN Board mounted, No air flow TYP 12 °C/ W Vtest R1 = 165 Ω B+ A RL = 75 Ω VOD B– CE and DE/RE at 2 V, WRAP1 and WRAP2 at 0.8 V R2 = 165 Ω Vtest Figure 1. Driver VOD Test Circuit CE at 2 V, DE/RE and WRAP1 or WRAP2 at 0.8 V (see Note A) – II, – IIH, or – IIL VI, VIC, VIH, or VIL VIT +, VIT – , or VID B+ A B– VOH or VOL NOTE A: For the IOZ measurement, CE is at 0.8 V. Figure 2. Receiver Test Circuit and Input Conditions 6 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 UNIT °C/ W PARAMETER MEASUREMENT INFORMATION 0 V or 3 V MAX 50 – IOH, – IOL, or – IOZ SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 PARAMETER MEASUREMENT INFORMATION B+ B– A – IIH or – IIL VIH or VIL VOD – IOH, – IOL, – IOS, or – IOZ VO, VOH, or VOL CE and DE/RE at 2 V, WRAP1 and WRAP2 at 0.8 V (see Note A) NOTE A: For the IOZ test, the CE input is at 0.8 V. Figure 3. Driver Test and Input Conditions GND R1 = 165 Ω B+ A Input (see Note A) RL = 75 Ω Output B– R2 = 165 Ω 50 pF† 50 pF† 5V CE and DE/RE at VCC TEST CIRCUIT 3V 1.5 V 0V Input td(ODH) Output td(ODL) 90% 90% 10% tr 10% 0V tf VOLTAGE WAVEFORMS † Includes probe and jig capacitance. NOTE A: The input is provided by a pulse generator with an output of 0 to 3 V, PRR of 1 MHz, 50% duty cycle, tr and tf < 6 ns, and ZO = 50 Ω. Figure 4. Driver Propagation Delay Time Test Circuit and Waveforms POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 7 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 PARAMETER MEASUREMENT INFORMATION CE at VCC, DE/RE, WRAP1 and WRAP2 at GND Input (see Note A) B+ 1.5 V B– A 15 pF† Output TEST CIRCUIT 3V 1.5 V 0V Input tPLH tPHL 90% Output 90% 10% tr 10% VOH 1.4 V VOL tf VOLTAGE WAVEFORMS † Includes probe and jig capacitance. NOTE A: The input is provided by a pulse generator with an output of 0 to 3 V, PRR of 1 MHz, 50% duty cycle, tr and tf < 6 ns, and ZO = 50 Ω. Figure 5. Receiver Propagation Delay Time Test Circuit and Waveforms 8 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 PARAMETER MEASUREMENT INFORMATION 0V 3V S1 0V S3 5V R1 = 165 Ω 74HC241 B+ A 50 pF† 75 Ω 50 pF† B– VOD R2 = 165 Ω DE/RE Input (see Note A) CE at VCC, WRAP1 and WRAP2 at GND 5V S2 0V VA TEST CIRCUIT 3V Input 0V ten(RXL) VA 1.4 V S1 to 0 V S2 to 5 V S3 to 3 V ten(TXH) 0V VOD 3V Input 0V ten(RXH) 1.4 V VA S1 to 5 V S2 to 0 V S3 to 0 V ten(TXL) VOD 0V VOLTAGE WAVEFORMS † Includes probe and jig capacitance. NOTE A: The input is provided by a pulse generator with an output of 0 to 3 V, PRR of 1 MHz, 50% duty cycle, tr and tf < 6 ns, and ZO = 50 Ω. Figure 6. Enable Time Test Circuit and Voltage Waveforms POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 9 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 TYPICAL CHARACTERISTICS INPUT CURRENT vs INPUT VOLTAGE AVERAGE SUPPLY CURRENT vs FREQUENCY 0 400 –10 I I – Input Current – µ A I CC – Average Supply Current – mA 1000 100 40 9 Unloaded Receivers 10 4 1 0.001 9 Unloaded Drivers 0.004 0.01 VCC = 4.75 V TA = 25°C A, DE/RE, WRAP1, WRAP2 – 20 – 30 – 40 – 50 0.04 1 2 4 – 60 0 10 0.5 1 1.5 f – Frequency – MHz INPUT CURRENT vs INPUT VOLTAGE 5 4 VCC = 4.75 V TA = 25°C B + and B – 3 I I – Input Current – mA 2.5 Figure 8 Figure 7 2 1 0 –1 –2 –3 –4 –5 – 20 –16 –12 – 8 – 4 0 4 8 12 VI – Input Voltage – V Figure 9 10 2 3 VI – Input Voltage – V POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 16 20 3.5 4 4.5 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 TYPICAL CHARACTERISTICS DRIVER DRIVER LOW-LEVEL OUTPUT VOLTAGE vs LOW-LEVEL OUTPUT CURRENT HIGH-LEVEL OUTPUT VOLTAGE vs HIGH-LEVEL OUTPUT CURRENT 5 2.1 VOH – High-Level Output Voltage – mV 1.9 1.8 1.7 1.6 1.5 1.4 1.3 4.75 4.5 4.25 4 VCC = 5.25 V 3.75 VCC = 5 V 3.5 3.25 3 2.75 1.2 VCC = 4.75 V 2.5 1.1 0 10 20 30 40 50 60 70 80 0 90 100 10 20 30 40 50 60 70 80 90 IOH – High-Level Output Current – mA IOL – Low-Level Output Current – mA Figure 10 Figure 11 DRIVER DIFFERENTIAL OUTPUT VOLTAGE vs OUTPUT CURRENT 5 TA = 25°C VOD – Differential Output Voltage – V VOL – Low-Level Output Voltage – V B+ and B – VCC = 5 V B+ and B – 2 4 3 VCC = 5 V 2 VCC = 5.25 V 1 VCC = 4.75 V 0 0 10 20 30 40 50 60 70 80 90 100 IO – Output Current – mA Figure 12 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 11 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 TYPICAL CHARACTERISTICS DRIVER DRIVER LOW-LEVEL OUTPUT CURRENT vs SUPPLY VOLTAGE HIGH-LEVEL OUTPUT CURRENT vs SUPPLY VOLTAGE 80 0 B+ and B – 70 I OH – High-Level Output Current – mA I OL – Low-Level Output Current – mA B+ and B – 60 50 40 30 20 10 0 2 2.5 3 3.5 4 4.5 5 –10 – 20 – 30 – 40 – 50 – 60 – 70 – 80 5.5 2 2.5 VCC – Supply Voltage – V 3 Figure 13 4 4.5 5 5.5 Figure 14 RECEIVER RECEIVER HIGH-LEVEL OUTPUT VOLTAGE vs HIGH-LEVEL OUTPUT CURRENT LOW-LEVEL OUTPUT VOLTAGE vs LOW-LEVEL OUTPUT CURRENT 2 5.5 VCC = 5 V VOL – Low-Level Output Voltage – V 5 VOH – High-Level Output Voltage – V 3.5 VCC – Supply Voltage – V 4.5 VCC = 5.25 V 4 VCC = 5 V 3.5 3 2.5 2 1.5 VCC = 4.75 V 1 VCC = 4.75 V 1.5 VCC = 5.25 V 1 0.5 0.5 0 0 0 –10 – 20 – 30 – 40 – 50 – 60 –70 IOH – High-Level Output Current – mA 0 10 Figure 15 12 20 30 Figure 16 POST OFFICE BOX 655303 40 50 IOL – Low-Level Output Current – mA • DALLAS, TEXAS 75265 60 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 TYPICAL CHARACTERISTICS RECEIVER DRIVER PROPAGATION DELAY vs FREE-AIR TEMPERATURE DIFFERENTIAL OUTPUT VOLTAGE vs FREE-AIR TEMPERATURE 26.5 1 tpd – Propagation Delay Time – ns 0.8 0.6 0.4 0.2 0 160 26 VCC = 4.75 V 25.5 25 VCC = 5.25 V 24.5 24 165 175 170 0 10 20 30 40 50 60 70 TA – Free-Air Temperature – °C TA – Free-Air Temperature – °C Figure 17 Figure 18 DRIVER PROPAGATION DELAY TIME vs FREE-AIR TEMPERATURE 23 22 tpd – Propagation Delay Time – ns VOD – Differential Output Voltage – V B+ and B – 21 VCC = 4.75 V 20 19 18 VCC = 5.25 V 17 16 15 0 10 20 30 40 50 60 70 TA – Free-Air Temperature – °C Figure 19 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 13 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 APPLICATION INFORMATION function tables Table 1. Channel Configuration for Totem Pole Circuit Table 2. Channel Configuration for Emitter Follower Circuit CE is high, WRAP1 or WRAP2 is high CE is high, WRAP1 or WRAP2 is low Emitter Follower Totem Pole DE/RE B+ A B– B+ DE/RE A B– Open Collector INPUTS DE/RE L L H H A X X L H B +† L H X X OUTPUTS B –† H L X X A L H Z Z B+ Z Z L H Z Z H L H = high level L = low level X = irrelevant Z = high impedance † An H in this column represents a voltage 200 mV higher than the other bus input. An L represents a voltage 200 mV lower than the other bus input. Any voltage less than 200 mV results in an indeterminate receiver output. 14 INPUTS B– POST OFFICE BOX 655303 OUTPUTS DE/RE B+ B– A B+ B– L L H H L H X X H L X X L H H H Z Z H H Z Z L L H = high level L = low level X = irrelevant Z = high impedance • DALLAS, TEXAS 75265 SN75LBC978 9-CHANNEL DIFFERENTIAL TRANSCEIVER SLLS134E – APRIL 1992 – REVISED MAY 1997 MECHANICAL INFORMATION DL (R-PDSO-G**) PLASTIC SMALL-OUTLINE PACKAGE 48 PIN SHOWN 0.025 (0,635) 0.012 (0,305) 0.008 (0,203) 48 0.005 (0,13) M 25 0.006 (0,15) NOM 0.299 (7,59) 0.291 (7,39) 0.420 (10,67) 0.395 (10,03) Gage Plane 0.010 (0,25) 1 0°– 8° 24 0.040 (1,02) A 0.020 (0,51) Seating Plane 0.110 (2,79) MAX 0.004 (0,10) 0.008 (0,20) MIN PINS ** 28 48 56 A MAX 0.380 (9,65) 0.630 (16,00) 0.730 (18,54) A MIN 0.370 (9,40) 0.620 (15,75) 0.720 (18,29) DIM 4040048 / C 03/97 NOTES: A. B. C. D. All linear dimensions are in inches (millimeters). This drawing is subject to change without notice. Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15). Falls within JEDEC MO-118 POST OFFICE BOX 655303 • DALLAS, TEXAS 75265 15 IMPORTANT NOTICE Texas Instruments (TI) reserves the right to make changes to its products or to discontinue any semiconductor product or service without notice, and advises its customers to obtain the latest version of relevant information to verify, before placing orders, that the information being relied on is current and complete. TI warrants performance of its semiconductor products and related software to the specifications applicable at the time of sale in accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent TI deems necessary to support this warranty. Specific testing of all parameters of each device is not necessarily performed, except those mandated by government requirements. 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