UM3085E/UM3088E ±15kV ESD-Protected, Slew-Rate-Limited, Fail-Safe, True RS-485 Transceivers UM3085E/UM3088E SOP8/DIP8 General Description The UM3085E, UM3088E are ±15kV ESD-protected, high-speed transceivers for RS-485 communication that contain one driver and one receiver. These devices feature fail-safe circuitry, which guarantees a logic-high receiver output when the receiver inputs are open, shorted or idle. This means that the receiver output will be logic high if all transmitters on a terminated bus are disabled (high impedance). The UM3085E features reduced slew-rate driver that minimizes EMI and reduces reflections caused by improperly terminated cables, allowing error-free data transmission up to 500kbps. While partially slew-rate limited UM3088E speeds up to 2.5Mbps. All devices feature enhanced ESD protection. All transmitter outputs and receiver inputs are protected to ±15kV using the Human Body Model and IEC61000-4-2, Air-Gap Discharge. The transceivers typically draw 400μA of supply current when unloaded, or when fully loaded with the drivers disabled. All devices have a 1/8-unit-load receiver input impedance that allows up to 256 transceivers on the bus and are intended for half-duplex communications. Applications Features RS-485 Transceivers Level Translators Industrial-Control Local Area Networks Transceivers for EMI-Sensitive Applications ESD Protection for RS-485 I/O Pins ±15kV—Human Body Model ±15kV—IEC61000-4-2, Air-Gap Discharge True Fail-Safe Receiver while Maintaining EIA/TIA-485 Compatibility Enhanced Slew-Rate Limiting Facilitates Error-Free Data Transmission 2nA Low-Current Shutdown Mode -7V to +12V Common-Mode Input Voltage Range Allows up to 256 Transceivers on the Bus Thermal Shutdown Current-Limiting for Driver Overload Protection Ordering Information UM3085EESA Operating Temperature -40°C to +85°C UM3085EEPA -40°C to +85°C UM3085EEPA DIP8 UM3088EESA -40°C to +85°C UM3088EESA SOP8 UM3088EEPA -40°C to +85°C UM3088EEPA DIP8 Part Number Marking Code Packaging Type UM3085EESA SOP8 Selection Guide Part Number UM3085E UM3088E Guaranteed Date Rate (Mbps) 0.5 2.5 Low-Power Shutdown Slew-Rate Limited Yes Yes Yes Yes Driver/ Receiver Enable Yes Yes Shutdown Current (nA) 2 2 Transceivers On Bus 256 256 ±15kV ESD Protection Yes Yes ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 1/12 UM3085E/UM3088E Absolute Maximum Ratings Symbol Parameter Value Unit VCC Supply Voltage +7 V Control Input Voltage (R E , DE) -0.3V to (VCC + 0.3V) V Driver Input Voltage (DI) -0.3V to (VCC + 0.3V) V Driver Output Voltage (A, B) -7.5 to +12.5 V Receiver Input Voltage (A, B) -7.5 to +12.5 V Receiver Output Voltage (RO) -0.3V to (VCC + 0.3V) V TA Ambient Temperature -40 to +85 °C TSTG Storage Temperature Range -65 to +160 °C TL Lead Temperature for Soldering 10 seconds +300 °C ______ DC Electrical Characteristics (VCC = +5V ± 5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Note 1) Parameter Symbol Test Conditions Min Typ Max Unit SUPPLY CURRENT DE=VCC, ______ No Load, RE=0V or VCC 0.3 ICC Supply Current DI=GND mA DE=0V, or VCC ______ 0.25 RE=0V Supply Current in Shutdown Mode LOGIC ISHDN ______ DE=GND, RE=VCC 0.002 10 µA ______ Input High Voltage VIH1 DE, DI, RE Input Low Voltage VIL1 DE, DI, RE DI Input Hysteresis VHYS UM3085E Differential Driver Output VOD1 No Load, Figure 2 Differential Driver Output VOD2 Figure 2, R=50Ω Change-in-Magnitude of Differential Output Voltage Driver Common-Mode Output Voltage ΔVOD Figure 2, R=50Ω (Note 2) 0.2 V VOC Figure 2, R=50Ω 3.0 V Change-in-Magnitude of Common-Mode Voltage ΔVOC Figure 2, R=50Ω (Note 2) 0.2 V Driver Short-Circuit Output Current (Note 3) IOSD 2.0 V ______ 0.8 100 V mV DRIVER 5 1.5 V V VOUT= -7V -250 VOUT=12V 250 mA ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 2/12 UM3085E/UM3088E DC Electrical Characteristics (Continued) (VCC = +5V ± 5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) (Note 1) Parameter Symbol Test Conditions Min Typ Max Unit RECEIVER Receiver Differential Threshold Voltage VTH -7V≤VCM≤12V Receiver Input Hysteresis ΔVTH VCM=0V Receiver Input Resistance RIN -7V≤VCM≤12V Input Current (A and B) IIN2 DE=GND, VCC=GND or 5V -200 -50 25 mV mV 96 kΩ VIN=12V 1.0 VIN= -7V -0.8 mA Receiver Output High Voltage VOH IO= -1.5mA, VID=200mV VCC -1.5 Receiver Output Low Voltage VOL IO=2.5mA, VID=200mV 0.4 V Three-State Output Current at Receiver IOZR VCC=5V, 0V≤VO≤VCC ±1 µA Receiver Output Short Circuit Current IOSR 0V≤VRO≤VCC ±60 mA ±8 V ESD Protection Human Body Model ±15 kV IEC61000-4-2 Air ±15 Discharge IEC61000-4-2 Contact ±8 Note 1: All currents into the device are positive; all currents out of the device are negative. All voltages are referred to device ground unless otherwise noted. Note 2: ΔVOD and ΔVOC are the changes in VOD and VOC, respectively, when the DI input changes state. Note 3: Maximum current level applies to peak current just prior to fold back current limiting; minimum current level applies during current limiting. ESD Protection for A, B ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 3/12 UM3085E/UM3088E Switching Characteristics (UM3085E) (VCC = +5V ± 5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) Parameter Symbol Test Conditions Min Typ Max Unit Maximum Data Rate Driver Input-to-Output fMAX tDPLH tDPHL 500 Figure 3 and 7, RDIFF=54Ω, CL1=CL2=100pF kbps 250 720 1000 250 720 1000 3 100 ns 530 750 ns 2500 ns 2500 ns 100 ns 100 ns 127 200 ns 3 30 ns 20 50 ns ns Driver Output Skew |tDPLH - tDPHL| tDSKEW Figure 3 and 7, RDIFF=54Ω, CL1=CL2=100pF Driver Rise or Fall Time tDR, tDF Figure 3 and 7, RDIFF=54Ω, CL1=CL2=100pF Driver Enable to Output High tDZH Driver Enable to Output Low tDZL Driver Disable Time from Low tDLZ Driver Disable Time from High tDHZ Receiver Input to Output tRPLH, tRPHL Differential Receiver Skew |tRPLH - tRPHL| tRSKD Receiver Enable to Output Low tRZL Receiver Enable to Output High tRZH Figure 5 and 10, CL=100pF, S2 Closed 20 50 ns Receiver Disable Time from Low tRLZ Figure 5 and 10, CL=100pF, S1 Closed 20 50 ns Receiver Disable Time from High tRHZ Figure 5 and 10, CL=100pF, S2 Closed 20 50 ns Time to Shutdown tSHDN (Note 4) 200 600 ns 200 Figure 4 and 8, CL=100pF, S2 Closed Figure 4 and 8, CL=100pF, S1 Closed Figure 4 and 8, CL=15pF, S1 Closed Figure 4 and 8, CL=15pF, S2 Closed |VID|≥2.0V, Rise and Fall Time of VID≤15ns Figure 6 and 9, |VID|≥2.0V, Rise and Fall Time of VID≤15ns Figure 5 and 10, CL=100pF, S1 Closed 50 Driver Enable from t Shutdown to Output High DZH(SHDN) Figure 4 and 8, CL=15pF, S2 Closed 4500 ns Driver Enable from Shutdown to Output Low tDZL(SHDN) Figure 4 and 8, CL=15pF, S1 Closed 4500 ns Receiver Enable from Shutdown to Output High tRZH(SHDN) Figure 5 and 10, CL=100pF, S2 Closed 3500 ns Receiver Enable from Shutdown to Output Low Figure 5 and 10, CL=100pF, S1 Closed 3500 ns tRZL(SHDN) ______ Note 4: The device is put into shutdown by bringing RE high and DE low. If the enable inputs are in this state for less than 50ns, the device is guaranteed not to enter shutdown. If the enable inputs are in this state for at least 600ns, the device is guaranteed to have entered shutdown. ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 4/12 UM3085E/UM3088E Switching Characteristics (UM3088E) (VCC = +5V ± 5%, TA = TMIN to TMAX, unless otherwise noted. Typical values are at VCC = +5V and TA = +25°C.) Parameter Symbol Test Conditions Min Typ Max Unit Maximum Data Rate Driver Input-to-Output fMAX tDPLH tDPHL 2.5 Figure 3 and 7, RDIFF=54Ω, CL1=CL2=100pF Mbps 34 60 34 60 ns Driver Output Skew |tDPLH - tDPHL| tDSKEW Figure 3 and 7, RDIFF=54Ω, CL1=CL2=100pF 2.5 10 ns Driver Rise or Fall Time tDR, tDF Figure 3 and 7, RDIFF=54Ω, CL1=CL2=100pF 14 25 ns Driver Enable to Output High tDZH 150 ns Driver Enable to Output Low tDZL 150 ns Driver Disable Time from Low tDLZ 100 ns Driver Disable Time from High tDHZ 100 ns Receiver Input to Output tRPLH, tRPHL 106 150 ns Differential Receiver Skew |tRPLH - tRPHL| tRSKD 0 10 ns Receiver Enable to Output Low tRZL 20 50 ns Receiver Enable to Output High tRZH Figure 5 and 10, CL=100pF, S2 Closed 20 50 ns Receiver Disable Time from Low tRLZ Figure 5 and 10, CL=100pF, S1 Closed 20 50 ns Receiver Disable Time from High tRHZ Figure 5 and 10, CL=100pF, S2 Closed 20 50 ns Time to Shutdown tSHDN (Note 4) 200 600 ns Figure 4 and 8, CL=100pF, S2 Closed Figure 4 and 8, CL=100pF, S1 Closed Figure 4 and 8, CL=15pF, S1 Closed Figure 4 and 8, CL=15pF, S2 Closed |VID|≥2.0V, Rise and Fall Time of VID≤15ns Figure 6 and 9, |VID|≥2.0V, Rise and Fall Time of VID≤15ns Figure 5 and 10, CL=100pF, S1 Closed 50 Driver Enable from t Shutdown to Output High DZH(SHDN) Figure 4 and 8, CL=15pF, S2 Closed 250 ns Driver Enable from Shutdown to Output Low tDZL(SHDN) Figure 4 and 8, CL=15pF, S1 Closed 250 ns Receiver Enable from Shutdown to Output High tRZH(SHDN) Figure 5 and 10, CL=100pF, S2 Closed 3500 ns Receiver Enable from Shutdown to Output Low Figure 5 and 10, CL=100pF, S1 Closed 3500 ns tRZL(SHDN) ______ Note 4: The device is put into shutdown by bringing RE high and DE low. If the enable inputs are in this state for less than 50ns, the device is guaranteed not to enter shutdown. If the enable inputs are in this state for at least 600ns, the device is guaranteed to have entered shutdown. ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 5/12 UM3085E/UM3088E Pin Description Pin Number Symbol 1 RO ______ Function Receiver Output. If A＞B by -50mV, RO will be high; if A＜B by 200mV, RO will be low. ______ Receiver Output Enable. Drive RE low to______ enable Receiver, RO is ______ high impedance when RE is high. Drive RE high and DE low to enter low-power shutdown mode. Driver Enable. Drive DE high to enable ______ drivers. The outputs are high impedance when DE is low. Drive RE high and DE low to enter low-power shutdown mode. Driver Input. A low on DI forces output A low and output B high. Similarly, a high on DI forces output A high and output B low. Ground. 2 RE 3 DE 4 DI 5 GND 6 A Non-Inverting Receiver Input and Non-Inverting Driver Output. 7 B Inverting Receiver Input and Inverting Driver Output. 8 VCC Power Supply for RS-485 Transceiver. RS-485 Communication Function Table Table1. Transmitting INPUTS ______ DE DI RE X 1 1 X 1 0 0 0 X 1 0 X X=Don’t care; High-Z=High Impedance OUTPUTS B A 0 1 1 0 High-Z High-Z High-Z High-Z MODE Normal Normal Normal Shutdown Table2. Receiving INPUTS DE A, B RE 0 X > -50mV 0 X < -200mV 0 X Inputs Open 1 0 X X=Don’t care; High-Z=High Impedance ______ OUTPUTS RO 1 0 1 High-Z MODE Normal Normal Normal Shutdown ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 6/12 UM3085E/UM3088E Typical Operating Circuit 120ohm 120ohm DI B DE B B D D A A A DE B RO RE A A B R RO RE R Master Node R DI Terminal Slave Node R D DI D DE RO RE Slave Node1 DI DE RO RE Slave Node N Figure 1. Typical Half-Duplex RS-485 Network Test Circuit B 3V DE RLOAD/2 CL2 A DI VOD2 RDIFF B VOD CL1 RLOAD/2 VOC A Figure 2. Driver DC Test Load Driver Output Under Test Figure 3. Driver Timing Test Circuit VCC 500ohm S1 Receiver Output VCC S1 + CRL 15pF + CL 1K Test Point 1K S2 S2 Figure 4. Driver Enable/Disable Timing Test Load Figure 5. Receiver Enable/Disable Timing Test Load B ATE R VD A Receiver Output Figure 6. Receiver Propagation Delay Test Circuit ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 7/12 UM3085E/UM3088E 5V 5V 1.5V DI 0V 1.5V tDPLH B 1.5V DE 0V tDPHL 1/2VO VO 1/2VO 1.5V tDZL(SHDN), tDZL B VOH tDLZ 2.3V A VOL VO 90% VDIFF = V B - V A VDIFF 0V -VO VOH 90% 2.3V t SKEW=|t DPLH-t DPHL| 10% VOL+0.5V Output Normally High VOH-0.5V A VOL tDZH(SHDN), tDZH 10% tDR Output Normally Low tDHZ tDF Figure 7. Driver Propagation Delays Figure 8. Driver Enable and Disable Times 5V RE VOH 0V RO VOL 1.5V OUTPUT tRPHL VOH 1.5V tRZL(SHDN), tRZL tRLZ 1.5V tRPLH A 1V INPUT B -1V 1.5V 1.5V Output Normally Low VOL+0.5V 1.5V Output Normally High VOH-0.5V RO VOL tRZH(SHDN), tRZH Figure 9. Receiver Propagation Delays tRHZ Figure 10. Receiver Enable and Disable Times Detail Description The UM3085E, UM3088E high-speed transceivers for RS-485 communication contain one driver and one receiver. These devices feature fail-safe circuitry, which guarantees a logic-high receiver output when the receiver inputs are open or shorted, or when they are connected to a terminated transmission line with all drivers disabled. The UM3085E features reduced slew-rate driver that minimizes EMI and reduces reflections caused by improperly terminated cables, allowing error-free data transmission up to 500kbps. While partially slew-rate limited UM3088E speeds up to 2.5Mbps. All of the parts operate from a single +5V supply. Drivers are output short-circuit current limited. Thermal shutdown circuitry protects drivers against excessive power dissipation. When activated, the thermal shutdown circuitry places the driver outputs into a high impedance state. Fail-Safe The UM3085E, UM3088E guarantees a logic-high receiver output when the receiver inputs are shorted or open, or when they are connected to a terminated transmission line with all drivers disabled. This is done by setting the receiver threshold between -50mV and -200mV. If the differential receiver input voltage (A-B) is greater than or equal to -50mV, RO is logic high. If A-B is less than or equal to -200mV, RO is logic low. In the case of a terminated bus with all transmitters disabled, the receiver’s differential input voltage is pulled to 0V by the termination. With the receiver thresholds of the UM3085E, UM3088E, this results in a logic high with a 50mV minimum noise margin. Unlike previous fail-safe devices, the -50mV to -200mV threshold complies with the ±200mV EIA/TIA-485 standard. ±15kV ESD Protection As with all Union devices, ESD-protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. The driver outputs and receiver inputs of the UM3085E, UM3088E have extra protection against static electricity. Union’s engineers have developed state-of-the-art structures to protect these pins against ESD of ±15kV without damage. The ESD-protected pins are tested with reference to the ground pin in a powered-down condition. They are tested to ±15kV using the Human Body Model. ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 8/12 UM3085E/UM3088E Applications Information 256 Transceivers on the Bus The standard RS-485 receiver input impedance is 12kΩ (one unit load), and the standard driver can drive up to 32 unit loads. The Union family of transceivers have a 1/8 unit load receiver input impedance (96kΩ), allowing up to 256 transceivers to be connected in parallel on one communication line. Any combination of these devices and/or other RS-485 transceivers with a total of 32 unit loads or less can be connected to the line. Reduced EMI and Reflections The UM3085E is slew-rate limited, minimizing EMI and reducing reflections caused by improperly terminated cables. In general, a transmitter’s rise time relates directly to the length of an unterminated stub, which can be driven with only minor waveform reflections. The following equation expresses this relationship conservatively: Length=tRISE / (10×1.5ns/ft) Where tRISE is the transmitter’s rise time. A system can work well with longer unterminated stubs, even with severe reflections, if the waveform settles out before the UART samples them. Low-Power Shutdown Mode ______ Low-power shutdown mode is initiated by bringing both R E high and DE low. In shutdown, the ______ device typically draws only 2nA of supply current. R E and DE may be driven simultaneously; ______ the parts are guaranteed not to enter shutdown if R E is high and DE is low for less than 50ns. If the inputs are in this state for at least 600ns, the parts are guaranteed to enter shutdown. Enable times tZH and tZL in the Switching Characteristics tables assume the part was not in a low-power shutdown state. Enable times tZH(SHDN) and tZL(SHDN) assume the parts were shut down. It takes drivers and receivers longer to become enabled from low-power shutdown mode (tZH(SHDN), tZL(SHDN)) than from driver/receiver-disable mode (tZH, tZL). Driver Output Protection Two mechanisms prevent excessive output current and power dissipation caused by faults or by bus contention. The first, a foldback current limit on the output stage, provides immediate protection against short circuits over the whole common-mode voltage range. The second, a thermal shutdown circuit, forces the driver outputs into a high-impedance state if the die temperature becomes excessive. Line Length vs. Data Rate The RS-485/RS-422 standard covers line lengths up to 4000 feet. For line lengths greater than 4000 feet, repeater is required. Typical Applications The UM3085E, UM3088E transceivers are designed for bidirectional data communications on multipoint bus transmission lines. To minimize reflections, the line should be terminated at both ends in its characteristic impedance, and stub lengths off the main line should be kept as short as possible. ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 9/12 UM3085E/UM3088E Package Information SOP8 Outline Drawing c L D E E1 Symbol 1 2 θ e End View A A2 Top View A1 b Side View A A1 A2 b c D E E1 e L θ DIMENSIONS MILLIMETERS Min Max 1.35 1.75 0.10 0.25 1.35 1.55 0.33 0.51 0.17 0.25 4.70 5.10 3.80 4.00 5.80 6.20 1.27BSC 0.40 1.27 0° 8° INCHES Min Max 0.053 0.069 0.004 0.010 0.053 0.061 0.013 0.020 0.006 0.010 0.185 0.200 0.150 0.157 0.228 0.244 0.050BSC 0.016 0.050 0° 8° 4.95 1.30 Land Pattern NOTES: 1.27 0.50 1. Compound dimension: 4.90×3.90； 2. Unit: mm; 3. General tolerance ±0.05mm unless otherwise specified; 4. The layout is just for reference. Tape and Reel Orientation XXXXXX XXXX XX ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 10/12 UM3085E/UM3088E DIP8 Outline Drawing E D1 E1 eA C eB Top View End View L A1 A3 A2 A D e b1 b Side View DIMENSIONS MILLIMETERS INCHES Symbol Min Max Min Max A 5.08 0.200 A1 0.38 0.015 A2 3.18 4.45 0.125 0.175 A3 1.40 2.03 0.055 0.080 b 0.41 0.56 0.016 0.022 b1 1.14 1.65 0.045 0.065 C 0.20 0.30 0.008 0.012 D 8.84 9.91 0.348 0.390 D1 0.13 2.03 0.005 0.080 E 7.62 8.26 0.300 0.325 E1 6.10 7.87 0.240 0.310 e 2.54 0.100 eA 7.62 0.300 eB 10.16 0.400 L 2.92 3.81 0.115 0.150 ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 11/12 UM3085E/UM3088E GREEN COMPLIANCE Union Semiconductor is committed to environmental excellence in all aspects of its operations including meeting or exceeding regulatory requirements with respect to the use of hazardous substances. Numerous successful programs have been implemented to reduce the use of hazardous substances and/or emissions. All Union components are compliant with the RoHS directive, which helps to support customers in their compliance with environmental directives. For more green compliance information, please visit: http://www.union-ic.com/index.aspx?cat_code=RoHSDeclaration IMPORTANT NOTICE The information in this document has been carefully reviewed and is believed to be accurate. Nonetheless, this document is subject to change without notice. Union assumes no responsibility for any inaccuracies that may be contained in this document, and makes no commitment to update or to keep current the contained information, or to notify a person or organization of any update. Union reserves the right to make changes, at any time, in order to improve reliability, function or design and to attempt to supply the best product possible. Union Semiconductor, Inc Add: Unit 606, No.570 Shengxia Road, Shanghai 201210 Tel: 021-51093966 Fax: 021-51026018 Website: www.union-ic.com ________________________________________________________________________ http://www.union-ic.com Rev.05 Sep.2015 12/12