DS481TN

DS481 NSC | Alldatasheet

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Technical content

Features

n Meets TIA/EIA RS-485 multipoint standard n Sleep mode reduces ICC to 0.2 µA n Guaranteed full load output voltage (VOD3 ) n Low quiescent current: 200 µA typ n −7V to +12V common-mode input voltage range n TRI-STATE outputs on driver and receiver n AC performance: — Driver transition time: 25 ns typ — Driver propagation delay: 40 ns typ — Driver skew: 1 ns typ — Receiver propagation delay: 200 ns typ — Receiver skew: 20 ns typ n Half-duplex flow through pinout n Operates from a single 5V supply n Allows up to 128 transceivers on the bus (DS481N/M) n Allows up to 64 tranceivers on the bus (DS481TN/M) n Current-limiting and thermal shutdown for driver overload protection n Industrial temperature range operation n Pin and functional compatible with MAX481C and MAX481E Connection and Logic Diagram Order Number Temp. Range Package/ ### DS481N 0˚C to +70˚C DIP/N08E DS481M 0˚C to +70˚C SOP/M08A DS481TN −40˚C to +85˚C DIP/N08E DS481TM −40˚C to +85˚C SOP/M08A Truth Table DRIVER SECTION RE (Note 1) DE DI A B XH H H L XH L L H X L X Z Z (Note 2) RECEIVER SECTION RE (Note 1) DE A-B RO LL ≥+0.2V H LL ≤−0.2V L H X X Z (Note 2) L L OPEN (Note 1) H X = indeterminate Z = TRI-STATE Note 1:Non Terminated, Open Input only Note 2:Device enters sleep mode if enable conditions are held> 600 ns, DE = L and RE (Note 1)= H. TRI-STATE® is a registered trademark of National Semiconductor Corporation. DS012919-1 *Note: Non Terminated, Open Input only July 1998 DS481 Low Power RS-485/RS-422 Multipoint Transceiver with Sleep Mode © 1999 National Semiconductor Corporation DS012919 www.national.com

Absolute Maximum Ratings(Note 3) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage (V CC ) +12V Enable Input Voltage (RE (Note 1), DE) −0.5V to (V CC + 0.5V) Driver Input Voltage (DI) −0.5V to (V CC + 0.5V) Driver Output Voltage (A, B) −14V to +14V Receiver Input Voltage (A, B) −14V to +14V Receiver Output Voltage (RO) −0.5V to (V CC + 0.5V) Maximum Package Power Dissipation@ +25˚C M Package 1.19W N Package 0.74W Derate M Package 9.5 mW/˚C above +25˚C Derate N Package 6.0 mW/˚C above +25˚C Maximum Package Power Dissipation @ +70˚C M Package 0.76W N Package 0.47W Storage Temperature Range −65˚C to +150˚C Lead Temperature Range (Soldering, 4 sec.) +260˚C ESD (HBM) ≥2k V Recommended Operating Conditions Min Typ Max Units Supply Voltage (VCC ) +4.75 +5.0 +5.25 V Operating Free Air Temperature (T DS481 0 +25 +70 ˚C DS481T −40 +25 +85 ˚C Bus Common Mode Voltage −7 +12 V

Electrical Characteristics

Over Supply Voltage and Operating Temperature Ranges, unless otherwise specified (Notes 4, 5) Symbol Parameter Conditions Pin Min Typ Max Units VOD1 Differential Driver Output Voltage (No Load) A, B 1.5 5 V VOD2 Differential Driver Output Voltage R L = 50Ω , (RS422),Figure 1 2 2.8 V with Load R L = 27Ω , (RS485),Figure 1 1.5 2.3 5 V ΔVOD Change in Magnitude of Output R L = 27Ω or 50Ω (Note 6) 0.2 |V| Differential Voltage VOD3 Differential Driver Output Voltage — R1 = 54Ω ,R 2= 375Ω 1.5 2.0 5 V Full Load with Max VCM VTEST = −7V to +12V,Figure 2 VOC Driver Common-Mode Output Voltage R L = 27Ω or 50Ω ,Figure 1 03 V ΔVOC Change in Magnitude of Common-Mode R L = 27Ω or 50Ω ,Figure 1 0.2 |V| Output Voltage (Note 6) VIH Input High Voltage DI, DE, RE (Note 1) 2.0 V VIL Input Low Voltage 0.8 V IIN1 Input Current V IN = 0V or VCC ±2µ A IIN2 Input Current (Note 7) DE = 0V, VCC = 0V or 5.25V VIN = +12V DS481 A, B 0 190 250 µA VIN = −7V 0 −100 −200 µA VIN = +12V DS481T 0 190 500 µA VIN = −7V 0 −100 −400 µA VTH Receiver Differential Threshold Voltage −7V≤ VCM ≤ +12V −0.2 0.2 V ΔVTH Receiver Input Hysteresis V CM = 0V 70 mV VOH Receiver Output High Voltage I O = −4 mA, VID = 0.2V RO 3.5 V VOL Receiver Output Low Voltage I O = 4 mA, VID = −0.2V 0.5 V IOZR TRI-STATE Output Current at Receiver 0.4V≤ V O ≤ 2.4V ±1µ A R IN Receiver Input Resistance −7V ≤ VIN ≤ +12V DS481 A, B 48 68 k Ω DS481T 24 ICC No-Load Supply Current (Note 8) DE = V CC , RE (Note 1)= 0V or V CC V CC 200 500 µA DE = 0V, RE (Note 1)= 0V or VCC 200 500 µA ICCX Sleep Mode Supply Current DE = GND V CC 0.2 10 µA RE (Note 1)= VCC (Figure 14) IOSD1 Driver Short Circuit Current, VO = HIGH −7V ≤ VO ≤ +12V A, B 250 mA IOSD2 Driver Short Circuit Current, VO = LOW −7V ≤ VO ≤ +12V −250 mA IOSR Receiver Short Circuit Current V O = GND RO 7 85 mA www.national.com 2

Over Supply Voltage and Operating Temperature Ranges, unless otherwise specified (Notes 5, 9, 10) Symbol Parameter Conditions Min Typ Max Units tPLHD Driver Differential Propagation Delay — Low to High RL = 54Ω ,C L = 100 pF 10 40 80 ns tPHLD Driver Differential Propagation Delay — High to Low 10 39 80 ns tSKEW Differential Skew |tPHLD −tPLHD |0 1 1 0 n s tr Driver Rise Time 32 5 5 0 n s tf Driver Fall Time 32 5 5 0 n s tZH Driver Enable to Output High C L = 100 pF 50 200 ns tZL Driver Enable to Output Low C L = 100 pF 65 200 ns tLZ Driver Disable from Output Low C L = 15 pF 80 200 ns tHZ Driver Disable from Output High C L = 15 pF 80 200 ns tPSH Driver Enable from Sleep C L = 100 pF 70 98 250 ns Mode to Output High (Note 12) (Figures 5, 6) tPSL Driver Enable from Sleep C L = 100 pF 70 98 250 ns Mode to Output Low (Note 12) (Figures 7, 8) tPLHD Receiver Differential Propagation Delay — Low to High CL = 15 pF (RO) 30 190 400 ns tPHLD Receiver Differential Propagation Delay — High to Low 30 210 400 ns tSKEW Differential Skew |tPHLD −tPLHD | 0 20 50 ns tZH Receiver Enable to Output High C L = 15 pF 45 150 ns tZL Receiver Enable to Output Low 40 150 ns tLZ Receiver Disable from Output Low 50 150 ns tHZ Receiver Disable from Output High 55 150 ns tPSH Receiver Enable from Sleep C L = 15 pF 70 97 250 ns Mode to Output High (Note 12) (Figures 11, 13) tPSL Receiver Enable from Sleep C L = 15 pF 70 95 250 ns Mode to Output Low (Note 12) (Figures 11, 12) tSLEEP Time to Sleep (Device) DE = L and RE (Note 1)= H 50 600 ns (Figure 14) fmax Maximum Data Rate (Note 11) 2.0 Mbps Note 3:“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 table of “Electrical Characteristics” specifies conditions of device operation. Note 4:Current into device pins is defined as positive. Current out of device pins is defined as negative. All voltages are referenced to ground except VOD1/2/3and VID. Note 5:All typicals are given for: VCC = +5.0V, TA = +25˚C. Note 6:Δ|VOD | andΔ|VOC | are changes in magnitude of VOD and VOC respectively, that occur when the input changes state. Note 7:IIN2 includes the receiver input current and driver TRI-STATE leakage current. Note 8:Supply current specification is valid for loaded transmitters when DE= 0V or enabled (DE= H) with no load. Note 9: f= 1 MHz, tr and tf≤ 6 ns, ZO = 50Ω . Note 10:C L includes jig and probe capacitance. Note 11:fmax is the guaranteed data rate for 50 ft of twisted pair cable. fmax may be conservatively determined from the ratio of driver transition time (tr) to the data Note 12:For enable from sleep mode delays DE= L and RE (Note 1)= H for greater than 600 ns prior to test (device is in sleep mode). www.national.com3

TABLE 1. Device Pin Descriptions

1 RO Receiver Output: When RE (Receiver Enable) is LOW, the receiver is enabled (ON), if DO/RI≥ DO

RO will be LOW. Additionally RO will be HIGH for OPEN (Non-terminated) Inputs. the device will enter a low-current sleep mode after 600 ns. enter a low-current sleep mode after 600 ns. (Note 1)/RI (Note 1) is LOW. 6 DO/RI Driver Output/Receiver Input, 485 Bus Pin. Driver Output/Receiver Input, 485 Bus Pin. CC Positive Power Supply Connection: Recommended operating range for VCC is +4.75V to +5.25V. sometimes desirable to have even more nodes. top and bottom borders shown inFigure 15are scaled also. FIGURE 14. Entering Sleep Mode Conditions (modes and exit parameters shown)

with tPZL and tPZH for timing differences. The benefit of the DS481 is definitely its power savings. When active the device has a maximum ICC of 500 µA. sleep mode the ICC is ultra low. FIGURE 15. Input Current vs Input Voltage

Physical Dimensionsinches (millimeters) unless otherwise noted Order Number DS481M or DS481TM Order Number DS481N or DS481TN www.national.com9

NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DE- VICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMI- CONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or sys- tems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose fail- 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. 2. A critical component is any component of a life support device or system whose failure to perform can be rea- sonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Corporation Americas Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com www.national.com National Semiconductor Europe Fax: +49 (0) 1 80-530 85 86 Email: europe.support@nsc.com 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: sea.support@nsc.com National Semiconductor Japan Ltd. Tel: 81-3-5639-7560 Fax: 81-3-5639-7507 DS481 Low Power RS-485/RS-422 Multipoint Transceiver with Sleep Mode 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.