DS36276 FAILSAFE Multipoint Transceiver General Description Features The DS36276 FAILSAFE Multipoint Transceiver is designed for use on bi-directional differential busses. It is compatible with existing TIA/EIA-485 transceivers, however, it offers an additional feature not supported by standard transceivers. The FAILSAFE feature guarantees the receiver output to a known state when the Interface is in the following conditions: Floating Line, Idle Line (no active drivers), and Line Fault conditions (open or short). The receiver output is in a HIGH state for the following conditions: OPEN Inputs, Terminated Inputs (50Ω), and SHORTED Inputs. FAILSAFE is a highly desirable feature when the transceivers are used with Asynchronous Controllers such as UARTs. n FAILSAFE receiver, RO = HIGH for: — OPEN inputs — Terminated inputs — SHORTED inputs n Compatible with popular interface standards: — TIA/EIA-485 (RS-485) — TIA/EIA-422-A (RS-422-A) — CCITT Recommendation V.11 n Bi-Directional Transceiver — Designed for multipoint transmission n Separate driver input, driver enable, receiver enable, and receiver output for maximum flexibility n Wide bus common mode range — (−7V to +12V) n Pin compatible with: DS75176B, DS96176, DS3695 and SN75176A and B n Available in SOIC package Connection and Logic Diagram Truth Tables Driver Inputs DS011383-1 Order Number DS36276M See NS Package Number M08A Outputs RE DE DI DO/RI X H H H L X H L L H X L X Z Z DO /RI Receiver Inputs Output RE DE RI–RI RO L L ≥0V H L L ≤−500 mV L H X X Z Receiver FAILSAFE Inputs Output RE DE RI–RI RO L L SHORTED H L L OPEN H H X X Z TRI-STATE ® is a registered trademark of National Semiconductor Corporation. © 1999 National Semiconductor Corporation DS011383 www.national.com DS36276 FAILSAFE Multipoint Transceiver July 1998 Absolute Maximum Ratings (Note 1) Lead Temperature (Soldering 4 sec.) Max Junction Temperature ESD Rating (HBM, 1.5 kΩ, 100 pF) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (VCC) 7V 5.5V Input Voltage (DE, RE , and DI) Driver Output Voltage/ Receiver Input Voltage −10V to +15V Receiver Output Voltage (RO) 5.5V Maximum Package Power Dissipation @ +25˚C M Package (derate 5.8 mW/˚C above +25˚C) 726 mW Storage Temperature Range −65˚C to +150˚C 260˚C 150˚C ≥ 6.0 kV Recommended Operating Conditions Min 4.75 −7 Max 5.25 +12 Units V V 0 +70 ˚C Min Typ Max 1.5 4.8 Supply Voltage, VCC Bus Voltage Operating Temperature (TA) DS36276 Electrical Characteristics (Notes 2, 4) Over recommended Supply Voltage and Operating Temperature ranges, unless otherwise specified. Symbol Parameter Conditions Units DRIVER CHARACTERISTICS VOD Differential Output Voltage IO = 0 mA (No Load) VoDO Output Voltage IO = 0 mA (Output to GND) VoDO Output Voltage VT1 Differential Output Voltage (Termination Load) ∆VT1 Balance of VT1 |VT1| − |VT1 | RL = 54Ω VOS Driver Common Mode Output Voltage RL = 54Ω ∆VOS IOSD Balance of VOS |VOS| − |VOS | Driver Short-Circuit Output Current 0 0 RL = 54Ω (485) 6.0 V 5.0 V 1.5 2.0 2.3 5.0 V (Note 3) −0.2 0.07 +0.2 V −0.2 0.07 +0.2 V 0 2.5 3.0 V 0 2.3 3.0 V RL = 100Ω (Figure 1) RL = 100Ω (Note 3) RL = 100Ω 2.0 −0.2 0.08 +0.2 V −0.2 0.08 +0.2 V 134 290 (Figure 3) VO = +12V V V (Figure 1) RL = 100Ω (422) RL = 54Ω 6.0 6.0 VO = VCC 140 mA mA VO = 0V −140 VO = −7V −180 −290 mA −0.18 0 V mA RECEIVER CHARACTERISTICS VTH Differential Input High Threshold Voltage (Note 5) VO = VOH, IO = −0.4 mA −7V ≤ VCM ≤ +12V VTL Differential Input Low Threshold Voltage (Note 5) VO = VOL, IO = 8.0 mA −7V ≤ VCM ≤ +12V VHST Hysteresis (Note 6) VCM = 0V IIN Line Input Current (VCC = 4.75V, 5.25V, 0V) Other Input = 0V DE = VIH (Note 7) −0.5 −0.23 V 50 mV VI = +12V 0.7 1.0 mA VI = −7V −0.5 −0.8 mA −30 −85 mA +20 µA IOSR Short Circuit Current VO = 0V IOZ TRI-STATE ® Leakage Current VO = 0.4 to 2.4V −20 VOH Output High Voltage (Figure 12) VID = 0V, IOH = −0.4 mA 2.5 3.5 V VID = OPEN, IOH = −0.4 mA 2.5 3.5 V Output Low Voltage (Figure 12 ) VID = −0.5V, IOL = +8 mA 0.25 0.6 VID = −0.5V, IOL = +16 mA 0.35 0.7 VOL RIN RO Input Resistance www.national.com −5.0 12 2 19 V V kΩ Electrical Characteristics (Notes 2, 4) (Continued) Over recommended Supply Voltage and Operating Temperature ranges, unless otherwise specified. Symbol Parameter Conditions Min Typ Max Units 2.0 VCC V GND 0.8 V 20 µA −100 µA DEVICE CHARACTERISTICS VIH High Level Input Voltage VIL Low Level Input Voltage IIH High Level Input Current IIL Low Level Input Current VIL = 0.4V VCL Input Clamp Voltage ICL = −18 mA ICC Output Low Voltage Supply Current (No Load) ICCR ICCD ICCX DE, RE, or DI VIH = 2.4V −0.75 −1.5 V DE = 3V, RE = 0V, DI = 0V 42 60 mA DE = 0V, RE = 0V, DI = 0V 28 45 mA DE = 3V, RE = 3V, DI = 0V 43 60 mA DE = 0V, RE = 3V, DI = 0V 31 50 mA Switching Characteristics (Note 4) Over recommended Supply Voltage and Operating Temperature ranges, unless otherwise specified. Symbol Parameter Conditions Min Typ Max Units 7 21 60 ns 7 19 60 ns 2 10 ns 12 50 ns 12 50 ns RL = 27Ω, CL = 15 pF (Figures 6, 7) 22 45 ns 22 45 ns RL = 110Ω CL = 50 pF (Figure 8 – Figure 11) 32 55 ns 32 65 ns 22 55 ns 16 55 ns 15 40 70 ns 15 42 70 ns 2 15 ns 15 50 ns ns DRIVER CHARACTERISTICS tPLHD Diff. Prop. Delay Low to High tPHLD Diff. Prop. Delay High to Low tSKD Diff. Skew (|tPLHD–tPHLD|) tr Diff. Rise Time tf Diff. Fall Time tPLH Prop. Delay Low to High tPHL Prop. Delay High to Low tPZH Enable Time Z to High tPZL Enable Time Z to Low tPHZ Disable Time High to Z tPLZ Disable Time Low to Z RL = 54Ω CL = 50 pF CD = 50 pF (Figures 4, 5) RECEIVER CHARACTERISTICS tPLH Prop. Delay Low to High tPHL Prop. Delay High to Low tSK Skew (|tPLH–tPHL|) tPZH Enable Time Z to High tPZL Enable Time Z to Low 17 50 tPHZ Disable Time High to Z 24 50 ns tPLZ Disable Time Low to Z 19 50 ns VID = −1.5V to +1.5V CL = 15 pF (Figures 13, 14) CL = 15 pF (Figures 15, 16) Note 1: “Absolute Maximum Ratings”are those values beyond which the safety of the device cannot be guaranteed. They are not meant to imply that the devices should be operated at these limits. The tables of “Electrical Characteristics” specify conditions for device operation. Note 2: Current into device pins is defined as positive. Current out of device pins is defined as negative. All voltages are referenced to ground unless otherwise specified. Note 3: ∆ |VT1| and ∆ |VOS| are changes in magnitude of VT1 and VOS, respectively, that occur when the input changes state. Note 4: All typicals are given for V CC = 5.0V and TA = +25˚C. Note 5: Threshold parameter limits specified as an algebraic value rather than by magnitude. Note 6: Hysteresis defined as VHST = VTH − VTL. Note 7: IIN includes the receiver input current and driver TRI-STATE leakage current. 3 www.national.com Parameter Measurement Information DS011383-2 FIGURE 1. Driver VT1 and VOS Test Circuit DS011383-3 FIGURE 2. Driver VOH and VOL Test Circuit DS011383-4 FIGURE 3. Driver Short Circuit Test Circuit DS011383-5 FIGURE 4. Driver Differential Propagation Delay and Transition Time Test Circuit www.national.com 4 Parameter Measurement Information (Continued) DS011383-6 FIGURE 5. Driver Differential Propagation Delays and Transition Times DS011383-7 FIGURE 6. Driver Propagation Delay Test Circuit DS011383-8 FIGURE 7. Driver Propagation Delays DS011383-9 S1 to DO for DI = 3V S1 to DO for DI = 0V FIGURE 8. Driver TRl-STATE Test Circuit (tPZH, tPHZ) 5 www.national.com Parameter Measurement Information (Continued) DS011383-10 FIGURE 9. Driver TRI-STATE Delays (tPZH, tPHZ) DS011383-11 S1 to DO for DI = 0V S1 to DO for DI = 3V FIGURE 10. Driver TRI-STATE Test Circuit (tPZL, tPLZ) DS011383-12 FIGURE 11. Driver TRl-STATE Delays (tPZL, tPLZ) DS011383-13 FIGURE 12. Receiver VOH and VOL DS011383-14 FIGURE 13. Receiver Propagation Delay Test Circuit www.national.com 6 Parameter Measurement Information (Continued) DS011383-15 FIGURE 14. Receiver Propagation Delays DS011383-16 FIGURE 15. Receiver TRI-STATE Delay Test Circuit DS011383-18 DS011383-17 S1 −1.5V S2 CLOSED S3 OPEN S1 1.5V S2 OPEN S3 CLOSED DS011383-20 DS011383-19 S1 −1.5V S2 CLOSED S3 CLOSED S1 1.5V S2 CLOSED S3 CLOSED Note 8: The input pulse is supplied by a generator having the following characteristics: f = 1.0 MHz, 50% duty cycle, tr and t f < 6.0 ns, ZO = 50Ω. Note 9: CL includes probe and stray capacitance. Note 10: Diodes are 1N916 or equivalent. FIGURE 16. Receiver Enable and Disable Timing 7 www.national.com Typical Performance Characteristics Differential Output Voltage vs Output Current Differential Output Voltage vs Output Current DS011383-21 Driver VOH vs IOH vs VCC DS011383-22 Driver VOH vs IOH vs Temperature DS011383-23 Driver VOL vs IOL vs VCC DS011383-24 Driver VOL vs IOL vs Temperature DS011383-25 www.national.com DS011383-26 8 Typical Performance Characteristics (Continued) Receiver VOH vs IOH vs VCC Receiver VOH vs IOH vs Temperature DS011383-27 Receiver VOL vs IOL vs VCC DS011383-28 Receiver VOL vs IOL vs Temperature DS011383-29 Supply Currrent vs Supply Voltage DS011383-30 Supply Current vs Temperature DS011383-31 DS011383-32 9 www.national.com Typical Performance Characteristics (Continued) Voltage Output vs Voltage Input (Hysteresis) DS011383-33 www.national.com 10 11 DS36276 FAILSAFE Multipoint Transceiver Physical Dimensions inches (millimeters) unless otherwise noted Order Number DS36276M NS Package Number M08A LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 2. A critical component is any component of a life support 1. Life support devices or systems are devices or sysdevice or system whose failure to perform can be reatems which, (a) are intended for surgical implant into sonably expected to cause the failure of the life support the body, or (b) support or sustain life, and whose faildevice or system, or to affect its safety or effectiveness. ure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: [email protected] www.national.com National Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: [email protected] Deutsch Tel: +49 (0) 1 80-530 85 85 English Tel: +49 (0) 1 80-532 78 32 Français Tel: +49 (0) 1 80-532 93 58 Italiano Tel: +49 (0) 1 80-534 16 80 National Semiconductor Asia Pacific Customer Response Group Tel: 65-2544466 Fax: 65-2504466 Email: [email protected] National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications.