MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers General Description Devices in the MAX3483AE family (MAX3483AE/ MAX3485AE/MAX3488AE/MAX3490AE/MAX3491AE) are ±20kV ESD-protected RS-485/422 transceivers, optimized for extended cable runs in noisy environments. All devices operate from a single 3.3V supply. The MAX3483AE and MAX3485AE are half-duplex transceivers. The MAX3488AE, MAX3490AE, and MAX3491AE are full-duplex transceivers. All receivers feature a unit-load input impedance, allowing up to 32 devices on a single bus. Each transceiver includes a fail-safe receiver, ensuring that the receiver output (RO) is high when inputs are shorted, open, or connected to a tri-state bus. Benefits and Features ● Integrated Protection Increases Robustness • High ESD Protection ±20kV HBM ESD per JEDEC JS-001-2012 ±15kV Air Gap per IEC 61000-4-2 ±8kV Contact ESD per IEC 61000-4-2 • Short-Circuit Protected Outputs • True Fail-Safe Receiver Prevents False Transition on Receiver Input Short or Open Events • Hot-Swap Capability Eliminates False Transitions During Power-Up or Hot Insertion ● High-Speed Data Rates up to 20Mbps All devices feature enhanced electrostatic discharge (ESD) protection. All transmitter outputs and receiver inputs are protected to ±20kV HBM ESD, ±15kV Air-Gap ESD and ±8kV Contact ESD in accordance to IEC 61000-4-2. ● Up to -40°C to +125°C Operating Temperature The MAX3483AE, MAX3485AE, MAX3488AE, and MAX3490AE are available in industry standard 8-pin SO package, while the MAX3491AE is available in a 14-pin SO package. ● Industrial-Control Local Area Networks ● Transceivers for EMI-Sensitive Applications ● Telecommuncations ● Allows Up to 128 Transceivers on the Bus Applications Ordering Information appears at end of data sheet. Functional Diagram A MAX3483AE MAX3485AE RO R RE R R RE VCC DE A DE DI Z DE DI D Y D MAX3488AE MAX3490AE B SHUTDOWN B SHUTDOWN 19-8506; Rev 0; 3/16 B VCC RE DI RO A RO Z D MAX3491AE Y MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Absolute Maximum Ratings (Voltages referenced to GND.) VCC ......................................................................-0.3V to +4.0V RO............................................................. -0.3V to (VCC + 0.3V) RE, DE, DI.............................................................-0.3V to +3.6V A, B, Y, Z.............................................................-9.0V to +13.0V Short-Circuit Duration (RO, A, B, Y, Z) to GND..........Continuous Operating Temperature Range MAX3483AE/85AE/88AE/90AE/91AE........... -40°C to +125°C MAX3488AE/90AE........................................ -40°C to +105°C Junction Temperature.......................................................+150°C Storage Temperature Range............................. -65°C to +150°C Continuous Power Dissipation (TA = +70°C) 8 SO (derate at 7.6mW/°C above +70°C)....................606mW 14 SO (derate at 11.9mW/°C above +70°C)................952mW Lead Temperature (soldering, 10s).................................. +300°C Soldering Temperature (reflow)....................................... +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 in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Package Thermal Characteristics (Note 1) Junction-to-Case Thermal Resistance (θJC) 8-pin SO.......................................................................38°C/W 14-pin SO.....................................................................34°C/W Junction-to-Ambient Thermal Resistance (θJA) 8-pin SO.....................................................................132°C/W 14-pin SO.....................................................................84°C/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four-layer board. For detailed information on package thermal considerations, refer to www.maximintegrated.com/thermal-tutorial. Electrical Characteristics (VCC = +3.0V to +3.6V, TA = TMIN to TMAX, unless otherwise specified. Typical values are at VCC = +3.3V and TA = +25°C.) (Notes 2, 3) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 3.6 V POWER SUPPLY Supply Voltage Supply Current Shutdown Supply Current 3.0 VCC ICC ISHDN DE = VCC, RE = GND, no load DE = 0, RE = 0, no load, DI = 0 or VCC 1.9 1.2 4 4.0 DE = GND, RE = VCC MAX3483AE/85AE/91AE 10 mA µA DRIVER Differential Driver Output VOD Change in Magnitude of Differential Output Voltage ∆VOD Driver Common-Mode Output Voltage VOC Change in Magnitude of CommonMode Voltage ΔVOC VCC = 3V, RL = 100Ω, Figure 1 2.0 VCC = 3V, RL = 54Ω, Figure 1 1.5 RL = 54Ω or 100Ω, Figure 1 (Note 4) -0.2 RL = 54Ω or 100Ω, Figure 1 -0.2 2.2 VOH A or B output, IA or B = -20mA Single-Ended Driver Output Low VOL A or B output, IA or B = 20mA Driver Short-Circuit Output Current IOSD www.maximintegrated.com VCC/2 RL = 54Ω or 100Ω, Figure 1 (Note 4) Single-Ended Driver Output High VOUT = -7V VOUT = +12V V +0.2 V 3 V +0.2 V V 0.8 -250 V mA 250 mA Maxim Integrated │ 2 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Electrical Characteristics (continued) (VCC = +3.0V to +3.6V, TA = TMIN to TMAX, unless otherwise specified. Typical values are at VCC = +3.3V and TA = +25°C.) (Notes 2, 3) PARAMETER SYMBOL CONDITIONS MIN TYP MAX 430 1000 UNITS RECEIVER VIN = +12V Input Current IA, B DE = GND, VCC = GND or +3.6V Differential Input Capacitance CA, B Between A and B, DE = GND, f = 4MHz Receiver Differential Threshold Voltage VTH Receiver Input Hysteresis ΔVTH Receiver Input Resistance RIN LOGIC INTERFACE (DI, DE, RE, RO) -7V ≤ VCM ≤ +12V 48 2.0 DE, DI, RE DE, DI, RE VHYS DE, DI, RE IIN DE, DI, RE DE, RE -105 µA pF -10 10 -7V ≤ VCM ≤ +12V, MAX3488AE/90AE/91AE VIL Input Impedance on First Transition -200 12 VIH 300 12 -7V ≤ VCM ≤ +12V, MAX3483AE/85AE Input Voltage Low Input Current -450 VCM = 0V Input Voltage High Input Hysteresis VIN = -7V mV mV kΩ V 0.8 50 1 V mV ±2 µA 10 kΩ RO Output Voltage High VOHRO RE = GND, IRO = -2mA, (VA - VB) > 200mV RO Output Voltage Low VOLRO RE = GND, IRO = 2mA, (VA - VB) < -200mV 0.4 V RE = VCC, 0 ≤ VRO ≤ VCC ±1 µA Receiver Three-State Output Current IOZR RE Pulldown and DE Pullup Resistance RIN Receiver Output Short-Circuit Current IOSR VCC - 1.5 V 1 0 ≤ VRO ≤ VCC mΩ ±110 mA PROTECTION Thermal Shutdown Threshold TSHDN Temperature rising +160 °C 15 °C IEC 61000-4-2 Air Gap Discharge to GND ±15 IEC 61000-4-2 Contact Discharge to GND ±8 Human Body Model to GND ±20 Human Body Model ±2 Thermal Shutdown Hysteresis ESD Protection on A, B, Z, and Y Pins ESD Protection, All Other Pins www.maximintegrated.com kV kV Maxim Integrated │ 3 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Switching Characteristics MAX3485AE/MAX3490AE/MAX3491AE (VCC = +3V to +3.6V, TA = TMIN to TMAX, unless otherwise specified. Typical values are at VCC = +3.3V and TA = +25°C.) (Notes 2, 3, 5) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DRIVER Driver Propagation Delay tDPLH tDPHL 30 RL = 54Ω, CL = 50pF, Figures 2 and 3 30 ns Driver Differential Output Rise or Fall Time tHL, tLH RL = 54Ω, CL = 50pF, Figures 2 and 3 7 ns Differential Driver Output Skew |tDPLH - tDPHL| tDSKEW RL = 54Ω, CL = 50pF, Figures 2 and 3 (Note 6) 3 ns Maximum Data Rate DRMAX 20 Mbps Driver Enable to Output High tDZH RL = 110Ω, CL = 50pF, MAX3485AE, MAX3491AE Figures 4 and 5 (Note 7) Driver Enable to Output Low tDZL RL = 110Ω, CL = 50pF, MAX3485AE, MAX3491AE Figures 4 and 5 (Note 7) 40 ns Driver Disable Time from Low tDLZ RL = 110Ω, CL = 50pF, MAX3485AE, MAX3491AE Figures 4 and 5 40 ns Driver Disable Time from High tDHZ RL = 110Ω, CL = 50pF, MAX3485AE, MAX3491AE Figures 4 and 5 40 ns RL = 110Ω, CL = 15pF, MAX3485AE, Figures 4 and 5 (Note 7) 6 µs 100 µs 6 µs 800 ns Driver Enable from Shutdown to Output High tDLZ(SHDN) MAX3491AE Driver Enable from Shutdown to Output Low Time to Shutdown tDHZ(SHDN) tSHDN RL = 110Ω, CL = 15pF, MAX3485AE Figures 4 and 5 (Note 7) (Note 8) 50 40 ns RECEIVER Receiver Propagation Delay tRPLH tRPHL Receiver Output Skew tRSKEW Maximum Data Rate DRMAX 35 CL = 15pF, Figures 6 and 7 35 CL = 15pF, Figures 6 and 7 (Note 6) 2 20 ns ns Mbps Receiver Enable to Output High tRZH RL = 1kΩ, CL = 15pF, MAX3485AE, MAX3491AE, Figure 8 (Note 7) Receiver Enable to Output Low tRZL RL = 1kΩ, CL = 15pF, MAX3485AE, MAX3491AE, Figure 8 (Note 7) 40 ns Receiver Disable Time from Low tRLZ RL = 1kΩ, CL = 15pF, MAX3485AE, MAX3491AE, Figure 8 40 ns www.maximintegrated.com 40 ns Maxim Integrated │ 4 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Switching Characteristics MAX3485AE/MAX3490AE/MAX3491AE (continued) (VCC = +3V to +3.6V, TA = TMIN to TMAX, unless otherwise specified. Typical values are at VCC = +3.3V and TA = +25°C.) (Notes 2, 3, 5) PARAMETER Receiver Disable Time from High SYMBOL tRHZ Receiver Enable from Shutdown to Output High tRLZ(SHDN) Receiver Enable from Shutdown to Output Low tRHZ(SHDN) Time to Shutdown tSHDN CONDITIONS MIN TYP RL = 1kΩ, CL = 15pF, MAX3485AE, MAX3491AE Figure 8 MAX UNITS 40 ns RL = 1kΩ, CL = 15pF, MAX3485AE, Figure 8 (Note 7) MAX3491AE RL = 1kΩ, CL = 15pF, MAX3485AE, Figure 8 (Note 7) 6 µs 100 µs 6 µs MAX3491AE 100 µs 800 ns (Note 8) 50 Switching Characteristics (MAX3483AE/MAX3488AE) (VCC = +3V to +3.6V, TA = TMIN to TMAX, unless otherwise specified. Typical values are at VCC = +3.3V and TA = +25°C.) (Notes 2, 3, 5) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DRIVER Driver Propagation Delay tDPLH tDPHL 1000 RL = 54Ω, CL = 50pF, Figures 2 and 3 Driver Differential Output Rise or Fall Time tHL, tLH RL = 54Ω, CL = 50pF, Figures 2 and 3 Differential Driver Output Skew |tDPLH - tDPHL| tDSKEW RL = 54Ω, CL = 50pF, Figures 2 and 3 Maximum Data Rate DRMAX 1000 200 ns 900 ns 140 ns kbps 500 Driver Enable to Output High tDZH RL = 110Ω, CL = 50pF, MAX3483AE Figures 4 and 5 (Note 6) 2500 ns Driver Enable to Output Low tDZL RL = 110Ω, CL = 50pF, MAX3483AE Figures 4 and 5 (Note 6) 2500 ns Driver Disable Time from Low tDLZ RL = 110Ω, CL = 50pF, MAX3483AE Figures 4 and 5 100 ns Driver Disable Time from High tDHZ RL = 110Ω, CL = 50pF, MAX3483AE Figures 4 and 5 100 ns RL = 110Ω, CL = 15pF, MAX3483AE Figures 4 and 5 (Note 6) 10 µs Driver Enable from Shutdown to Output High www.maximintegrated.com tDLZ(SHDN) Maxim Integrated │ 5 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Switching Characteristics (MAX3483AE/MAX3488AE) (continued) (VCC = +3V to +3.6V, TA = TMIN to TMAX, unless otherwise specified. Typical values are at VCC = +3.3V and TA = +25°C.) (Notes 2, 3, 5) PARAMETER Driver Enable from Shutdown to Output Low Time to Shutdown SYMBOL CONDITIONS tDHZ(SHDN) RL = 110Ω, CL = 15pF, MAX3483AE Figures 4 and 5 (Note 6) tSHDN (Note 8) MAX3483AE MIN 50 TYP 340 MAX UNITS 5.5 µs 700 ns RECEIVER Receiver Propagation Delay tRPLH tRPHL Receiver Output Skew tRSKEW Maximum Data Rate DRMAX 200 CL = 15pF, Figures 6 and 7 200 CL = 15pF, Figures 6 and 7 (Note 6) 30 500 ns ns kbps Receiver Enable to Output High tRZH RL = 1kΩ, CL = 15pF, MAX3483AE Figure 8 (Note 6) 50 ns Receiver Enable to Output Low tRZL RL = 1kΩ, CL = 15pF, MAX3483AE Figure 8 (Note 6) 50 ns Receiver Disable Time from Low tRLZ RL = 1kΩ, CL = 15pF, MAX3483AE Figure 8 50 ns Receiver Disable Time from High tRHZ RL = 1kΩ, CL = 15pF, MAX3483AE Figure 8 50 ns Receiver Enable from Shutdown to Output High tRLZ(SHDN) RL = 1kΩ, CL = 15pF, MAX3483AE Figure 8 (Note 6) 10 µs Receiver Enable from Shutdown to Output Low tRHZ(SHDN) RL = 1kΩ, CL = 15pF, MAX3483AE Figure 8 (Note 6) 10 µs tSHDN (Note 8) MAX3483AE 800 ns Time to Shutdown 50 340 Note 2: All devices 100% production tested at TA = +25°C. Specifications over temperature are guaranteed by design. Note 3: All currents into the device are positive; all currents out of the device are negative. All voltages are referenced to ground, unless otherwise noted. Note 4: ΔVOD and ΔVOC are the changes in VOD and VOC, respectively, when the DI input changes state. Note 5: Capacitive load includes test probe and fixture capacitance. Note 6: Guaranteed by design; not production tested. Note 7: The timing parameter refers to the driver or receiver enable delay, when the device has exited the initial hot-swap protect state and is in normal operating mode. Note 8: Shutdown is enabled by driving RE high and DE low. The device is guaranteed to have entered shutdown after tSHDN has elapsed. www.maximintegrated.com Maxim Integrated │ 6 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Test and Timing Diagrams A VCC DE RL 2 DI A VOD B VOD RL 2 RL CL VOC B Figure 1. Driver DC Test Load Figure 2. Driver Timing Test Circuit tLH = 3ns, tHL = 3ns VCC DI 1.5V 1.5V 0 tDPHL tDPLH B A VOD VOD = [VA - VB] VO VOD 90% 0 -VO 90% 10% 10% tLH tHL tDSKEW = |tDPLH - tDPHL| Figure 3. Driver Propagation Delays www.maximintegrated.com Maxim Integrated │ 7 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE GND OR VCC DI D A B +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers S1 VCC OUT CL 50pF RL = 110Ω DE 1.5V tDZH, tDZH(SHDN) DE GENERATOR 0 0.25V OUT 50Ω VOH 1.5V 0 tDHZ Figure 4. Driver Enable and Disable Times (tDZH, tDHZ) VCC 0 OR VCC DI D A RL = 110Ω S1 VCC OUT B VCC OUT DE GENERATOR DE 50Ω 1.5V tDZL, tDZL(SHDN) 0 tDLZ 1.5V VOL 0.25V Figure 5. Driver Enable and Disable Times (tDZL, tDLZ) A ATE R VID RO B Figure 6. Receiver Propagation Delay Test Circuit www.maximintegrated.com Maxim Integrated │ 8 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers A 1V B -1V tRPHL VOH RO tRPLH 1.5V 1.5V VOL tRSKEW = |tRPHL - tRPLH| Figure 7. Receiver Propagation Delays +1.5V S3 -1.5V VID R RO RE GENERATOR 1.5V tRZH, tRZH(SHDN) RO 0 S1 OPEN S2 CLOSED S3 = +1.5V VCC 1.5V tRHZ RO 0.25V VCC S2 CL 15pF VCC 1.5V RE 0 S1 CLOSED S2 OPEN S3 = -1.5V tRZL, tRZL(SHDN) VOH VCC 2 0 RE S1 50Ω VCC RE R 1kΩ 0 VCC 2 VOL RO VCC S1 OPEN S2 CLOSED S3 = +1.5V 1.5V RE tRLZ 0 S1 CLOSED S2 OPEN S3 = -1.5V VCC VOH 0 VCC RO 0.25V VOL Figure 8. Receiver Enable and Disable Times www.maximintegrated.com Maxim Integrated │ 9 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Typical Operating Characteristics (VCC = +3.3V, TA = +25°C, unless otherwise specified.) DE = VCC RE = GND 30 MAX3483AE 2 1.5 MAX3488AE/90AE/91AE MAX3485AE 1 0 MAX3488AE/90AE/91AE 15 0.5 MAX3483AE MAX3485AE 5 -40 -25 -10 5 0 20 35 50 65 80 95 110 125 -40 -25 -10 5 TEMPERATURE (°C) TOC04 60 DE = VCC RE = GND TOC05 MAX3483AE/85AE 2.0 MAX3485AE, NO LOAD 1.5 20 MAX3488AE/90AE/91AE 1.0 10 10 15 20 0.0 DATA RATE (Mbps) 0 10 20 30 40 150 200 250 TOC06 OUTPUT SINKING CURRENT 4 MAX3488AE/90AE/91AE 3 2 MAX3483AE/85AE 1 0 0 10 20 30 40 50 60 OUTPUT CURRENT (mA) OUTPUT CURRENT (mA) DIFFERENTIAL DRIVER OUTPUT VOLTAGE vs. TEMPERATURE TOC07 380 4.5 MAX3483AE/88AE - 500Kbps DRIVER PROPAGATION DELAY vs. TEMPERATURE TOC8 375 4 3.5 MAX3488AE/90AE91AE 3 2.5 2 1.5 MAX3483AE/85AE 1 PROPAGATION DELAY (ns) DIFFERENTIAL DRIVER OUTPUT VOLTAGE (V) 5 100 0.5 MAX3490AE/91AE, NO LOAD 5 50 RECEIVER OUTPUT LOW VOLTAGE vs. OUTPUT CURRENT 5 OUTPUT SOURCING CURRENT 2.5 MAX3490AE/91AE, 54Ω load 0 0 3.5 40 0 MAX3488AE, NO LOAD MAX3483AE NO LOAD DATA RATE (kbps) 3.0 30 20 0 20 35 50 65 80 95 110 125 VOH (V) SUPPLY CURRENT (mA) 50 MAX3488AE, 54Ω LOAD 30 10 RECEIVER OUTPUT HIGH VOLTAGE vs. OUTPUT CURRENT 4.0 MAX3485AE, 54Ω LOAD MAX3483AE, 54Ω LOAD 40 TEMPERATURE (°C) MAX3485AE/90AE/91AE – 20Mbps SUPPLY CURRENT vs. DATA RATE DE = VCC 50 20 10 MAX3483AE/88AE - 500Kbps SUPPLY CURRENT vs. DATA RATE TOC03 60 DE = GND RE = VCC 25 SUPPLY CURENT (mA) SUPPLY CURENT (mA) 2.5 SHUTDOWN SUPPLY CURRENT vs. TEMPERATURE TOC02 OUTPUT LOW VOLTAGE (V) 3 TOC01 SUPPLY CURENT (mA) NO LOAD SUPPLY CURRENT vs. TEMPERATURE 370 365 355 350 345 0 340 20 35 50 65 80 95 110 125 TEMPERATURE (°C) www.maximintegrated.com tDPLH, MAX3488AE 360 0.5 -40 -25 -10 5 tDPHL, MAX3488AE tDPLH, MAX3483AE tDPHL, MAX3483AE RL = 54Ω CL = 50pF -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) Maxim Integrated │ 10 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Typical Operating Characteristics (continued) (VCC = +3.3V, TA = +25°C, unless otherwise specified.) 18 tDPHL, MAX3490AE/91AE 14 tDPLH, MAX3485AE 12 RL = 54Ω CL = 50pF tDPHL, MAX3485AE -40 -25 -10 5 12 10 8 6 MAX3483AE 4 2 0 -40 -25 -10 5 MAX3483AE/88AE DRIVER OUTPUT RISE AND FALL TIME vs. TEMPERATURE TOC12 250 tLH, MAX3488AE tLH, MAX3483AE tHL, MAX3488AE 100 RL = 54Ω CL = 50pF 50 0 -40 -25 -10 5 DRIVER OUTPUT RISE/FALL TIME (ns) DIFFERENTIAL OUTPUT RISE/FALL TIME (ns) 300 150 7 6 5 4 6 2 -40 -25 -10 5 4 3 1 0 20 35 50 65 80 95 110 125 tLH, MAX3485A 5 2 tLH, MAX3490AE/91AE RL = 54Ω tHL, MAX3490AE/91AE CL = 50pF -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) TEMPERATURE (°C) DRIVER OUTPUT TRANSITION SKEW (ns) 4 20 35 50 65 80 95 110 125 TEMPERATURE (°C) MAX3485AE/90AE/91AE DRIVER OUTPUT RISE/FALL TIME vs. TEMPERATURE TOC13 tHL, MAX3485AE MAX3490AE/91AE MAX3485AE 3 0 20 35 50 65 80 95 110 125 7 350 200 8 tHL, MAX3483AE TOC11 RL = 54Ω CL = 50pF TEMPERATURE (°C) TEMPERATURE (°C) 400 8 MAX3485AE/90AE/91AE DIFFERENTIAL DRIVER SKEW vs. TEMPERATURE 1 MAX3488AE -2 -4 10 9 14 20 35 50 65 80 95 110 125 450 TOC10 RL = 54Ω CL = 50pF 60 DRIVER OUTPUT TRANSITION SKEW (ns) 16 16 MAX3483AE/88AE – 500Kbps DIFFERENTIAL DRIVER SKEW vs. TEMPERATURE DIFFERENTIAL DRIVER SKEW (ns) 18 10 20 tDPLH, MAX3490AE/91AE 20 PROPAGATION DELAY (ns) TOC9 DIFFERENTIAL DRIVER SKEW (ns) 22 MAX3485AE/90AE/91AE - 20Mbps DRIVER PROPOGATION DELAY vs. TEMPERATURE MAX3483AE/88AE DRIVER OUTPUT TRANSITION SKEW vs. TEMPERATURE TOC14 RL = 54Ω CL = 50pF 55 50 45 40 35 30 MAX3488AE 25 20 MAX3483AE 15 10 5 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) MAX3485AE/90AE/91AE DRIVER OUTPUT TRANSITION SKEW vs. TEMPERATURE TOC15 RL = 54Ω CL = 50pF 3.5 3 2.5 2 MAX3485AE 1.5 MAX3490AE/91AE 1 0.5 0 -40 -25 -10 5 20 35 50 65 80 95 110 125 TEMPERATURE (°C) www.maximintegrated.com Maxim Integrated │ 11 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Pin Configuration TOP VIEW RO RE DE DI 1 2 + 8 7 MAX3483AE MAX3485AE 3 6 4 5 1 RO 2 13 N.C. RE 3 12 A DE 4 DI 5 10 Z GND 6 9 Y GND 7 8 N.C. VCC B A GND + N.C. 14 VCC MAX3490AE SO 11 B + 8 A 7 B 3 6 Z 4 5 Y VCC 1 RO 2 DI GND MAX3488AE MAX3490AE SO SO Pin Description PIN NAME FUNCTION MAX3483AE MAX3485AE MAX3488AE MAX3490AE MAX3491AE — — 1, 8, 13 N.C. No Connection. Not internally connected. 1 2 2 RO Receiver Output. Drive RE low to enable RO. RO is always active on the MAX3488AE and MAX3490AE. RO is high when the receiver inputs (VA VB) > -10mV and low when (VA -VB) ≤200mV. See the Function Tables. 2 — 3 RE Receiver Output Enable. Drive RE low, or leave unconnected, to enable RO. RO is high impedance when RE is high. Drive RE high and DE low to enter low-power shutdown mode. RE has a weak pulldown to GND. DE Driver Enable. Drive DE high, or leave unconnected, to enable the driver outputs (Y and Z for full duplex, A and B for half duplex). The driver outputs are high impedance when DE is low. Drive RE high and DE low to enter low-power shutdown mode. DE has a weak pullup to VCC. Driver Input. A low on DI forces the noninverting output (Y or A) low and the inverting output (Z or B) high. Similarly, a high on DI forces the noninverting output (Y or A) high and the inverting output (Z or B) low. See the Function Tables. 3 — 4 4 3 5 DI 5 4 6, 7 GND — 5 9 Y Noninverting Driver Output — 6 10 Z Inverting Driver Output 7 7 11 B Inverting Receiver Input/Driver Output (MAX3483AE/MAX3485AE). Inverting Receiver Input (MAX3488AE/MAX3490AE/MAX3491AE). 6 8 12 A Noninverting Receiver Input/Driver Output (MAX3483AE/MAX3485AE). Noninverting Receiver Input (MAX3488AE/MAx3490AE/MAX3491AE). 8 1 14 VCC Positive Supply. Bypass VCC to GND with a 0.1µF capacitor as close as possible to the IC. www.maximintegrated.com Ground Maxim Integrated │ 12 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Function Tables (MAX3483AE, MAX3485AE) TRANSMITTING INPUTS RE OUTPUTS MODE DE DI B A X 1 1 0 1 Active X 1 0 1 0 Active 0 0 X High Impedance Driver Disabled 1 0 X High Impedance Shutdown RECEIVING INPUTS RE OUTPUTS MODE DE A-B RO 0 X ≥ -10mV 1 Active 0 X ≤ -200mV 0 Active 0 X Open/Shorted 1 Active 1 1 X High Impedance Receiver Disabled 1 0 X High Impedance Shutdown X = Don’t care Function Tables MAX3491AE TRANSMITTING INPUTS RE* OUTPUTS DE* DI Y Z X 1 1 1 0 X 1 0 0 1 0 0 X High-Impedance 1 0 X Shutdown RECEIVING RE* INPUTs OUTPUT DE* VA - VB RO 0 X ≥ -10mV 1 0 X ≤ -200mV 0 0 X Open/Shorted 1 1 1 X High-Impedance 1 0 X Shutdown *RE and DE on the MAX3488AE and MAX3490AE are internal. The driver outputs and receiver are always active in these devices. www.maximintegrated.com Maxim Integrated │ 13 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Detailed Description Hot-Swap Capability The device features fail-safe receiver inputs guaranteeing a logic-high receiver output when inputs are shorted or open. The MAX3483AE/85AE has a 1-unit load receiver input impedance, allowing up to 32 transceivers on the bus. The MAX3488AE/90AE/91AE has a 1/4-unit load receiver input impedance, allowing up to 128 transceivers on the bus. When circuit boards are inserted in a hot or powered backplane, disturbances on the enable inputs and differential receiver inputs can lead to data errors. Upon initial circuit board insertion, the processor undergoes its power-up sequence. During this period, the processor output drivers are high impedance and are unable to drive the DE and RE inputs MAX3483AE/85AE/91AE to a defined logic level. Leakage currents up to 10µA from the high-impedance outputs of a controller could cause DE and RE to drift to an incorrect logic state. Additionally, parasitic circuit board capacitance could cause coupling of VCC or GND to DE and RE. These factors could improperly enable the driver or receiver. The integrated hot-swap inputs help to avoid these potential problems. The MAX3483AE/85AE and MAX3488AE/90AE/91AE family are 3.3V ESD-protected RS-485/RS-422 transceivers intended for half-duplex or full-duplex communications. Integrated hot-swap functionality eliminates false transitions on the bus during power-up or hot insertion. True Fail Safe The transceiver family guarantee 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. If the differential receiver input voltage (A–B) is greater than or equal to -10mV, RO is logic-high. Driver Single-Ended Operation The driver outputs can either be used in the standard differential operating mode, or can be used as single-ended outputs. Since the driver outputs swing rail-to-rail, they can individually be used as standard TTL logic outputs. For half-duplex transceivers, driver outputs are A and B. For full-duplex transceivers, driver outputs are Y and Z. Hot-Swap Inputs When VCC rises, an internal pulldown circuit holds DE low and RE high. After the initial power-up sequence, the pulldown circuit becomes transparent, resetting the hotswap-tolerable inputs. Hot-Swap Input Circuitry The DE and RE enable inputs feature hot-swap capability. At the input, there are two nMOS devices, M1 and M2 (Figure 9). When VCC ramps from 0V, an internal 10µs timer turns on M2 and sets the SR latch that also turns on M1. Transistors M2 (a 500µA current sink) and M1 (a 100µA current sink) pull DE to GND through a 5kΩ (typ) VCC 10µs TIMER TIMER DE DRIVER ENABLE (HOT SWAP) 5kΩ (typ) 100µA M1 500µA M2 Figure 9. Simplified Structure of the Driver Enable (DE) Pin www.maximintegrated.com Maxim Integrated │ 14 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers resistor. M2 is designed to pull DE to the disabled state against an external parasitic capacitance up to 100pF that can drive DE high. After 10µs, the timer deactivates M2 while M1 remains on, holding DE low against three-state leakages that can drive DE high. M1 remains on until an external source overcomes the required input current. At this time, the SR latch resets and M1 turns off. When M1 turns off, DE reverts to a standard, high-impedance CMOS input. Whenever VCC drops below 1V, the hotswap input is reset. A complementary circuit employing two pMOS devices pulls RE to VCC. ±20kV ESD Protection ESD protection structures are incorporated on all pins to protect against electrostatic discharges encountered during handling and assembly. The driver outputs and receiver inputs have extra protection against static electricity. The ESD structures withstand high ESD in all states: normal operation, shutdown, and powered down. After an ESD event, the transceiver family keeps working without latch-up or damage. ESD protection can be tested in various ways. The transmitter outputs and receiver inputs are characterized for protection to the following limits: RC 1MΩ CHARGE CURRENTLIMIT RESISTOR HIGHVOLTAGE DC SOURCE CS 100pF RD 1.5kΩ Figure 10. Human Body ESD Test Model www.maximintegrated.com ● ±15kV using the Air-Gap Discharge method specified in IEC 61000-4-2 ● ±8kV using the Contact Discharge method specified in IEC 61000-4-2 ESD Test Conditions ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test setup, test methodology, and test results. Human Body Model (HBM) Figure 10 shows the HBM, and Figure 11 shows the current waveform it generates when discharged into a lowimpedance state. This model consists of a 100pF capacitor charged to the ESD voltage of interest, which is then discharged into the test device through a 1.5kΩ resistor. IEC 61000-4-2 The IEC 61000-4-2 standard covers ESD testing and performance of finished equipment. However, it does not specifically refer to integrated circuits. The transceiver family helps in designing equipment to meet IEC 61000-4-2 without the need for additional ESD protection components. The major difference between tests done using the HBM and IEC 61000-4-2 is higher peak current in IEC 61000-4-2 because series resistance is lower in the IEC 61000-4-2 model. Hence, the ESD withstand voltage measured to IEC 61000-4-2 is generally lower than that measured using the HBM. IP 100% 90% DISCHARGE RESISTANCE STORAGE CAPACITOR ● ±20kV HBM IR PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) AMPERES DEVICE UNDER TEST 36.8% 10% 0 0 tRL TIME tDL CURRENT WAVEFORM Figure 11. Human Body Current Waveform Maxim Integrated │ 15 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Figure 12 shows the IEC 61000-4-2 model, and Figure 13 shows the current waveform for IEC 61000-4-2 ESD Contact Discharge test. Applications Information RE and DE can be connected together and driven simultaneously. The transceiver is guaranteed not to enter shutdown if RE is high and DE is low for less than 50ns. If the inputs are in this state for at least 800ns (max), the device is guaranteed to enter shutdown. Driver Output Protection Typical Applications Two mechanisms prevent excessive output current and power dissipation caused by faults or by bus connection. The first, a current limit on the output stage provides immediate protection against short circuits over the whole common-mode voltage range. The second, a thermalshutdown circuit, forces the driver outputs into a highimpedance state if the die temperature exceeds +160°C (typ). The transceiver family is designed for bidirectional data communications on multipoint bus transmission lines. Figure 14 and Figure 15 show typical network application circuits. To minimize reflections, terminate the line at both ends with its characteristic impedance and keep stub lengths off the main line as short as possible. Low-Power Shutdown Mode (MAX3483AE, MAX3485AE,MAX3491AE) Low-power shutdown mode is initiated by bringing RE high and DE low. In shutdown, the devices draw less than 10µA of supply current. CHARGE CURRENTLIMIT RESISTOR HIGHVOLTAGE DC SOURCE CS 150pF RD 330Ω I 100% 90% DISCHARGE RESISTANCE IPEAK RC 50MΩ TO 100MΩ DEVICE UNDER TEST STORAGE CAPACITOR 10% tR = 0.7ns TO 1ns t 30ns 60ns Figure 12. IEC 61000-4-2 ESD Test Model Figure 13. IEC 61000-4-2 ESD Generator Current Waveform 120Ω DI DE B B D D DI DE RO 120Ω A B A B A A R R RE R R D MAX3483AE/85AE DI RO RE D DE RO RE DI DE RO RE Figure 14. Typical Application Circuit www.maximintegrated.com Maxim Integrated │ 16 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers A RO D R RE DE DI Y B Z Z B DI DE RE R D RO A Y Y Z A B Y Z A B DI DE A RO DI R D D R MAX3491AE RE RO DI DE RE RO Y D R B Z Z B R D Y DI RO A MAX3488AE MAX3490AE Figure 15. Typical Half-Duplex RS-485 Network www.maximintegrated.com Maxim Integrated │ 17 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Chip Information Package Information PROCESS: BiCMOS For the latest package outline information and land patterns (footprints), go to www.maximintegrated.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 SOIC S8+2 21-0041 90-0096 8 SOIC S8+4 21-0041 90-0096 14 SOIC S14+1 21-0041 90-0112 Ordering Information PART DUPLEX DATA RATE (MAX) PIN-PACKAGE PACKAGE CODE TEMPERATURE RANGE MAX3483AEASA+ Half 0.25Mbps 8 SO S8+2 -40°C to +125°C -40°C to +125°C MAX3485AEASA+ Half 20Mbps 8 SO S8+2 MAX3488AEGSA+ Full 0.25Mbps 8 SO S8+4 -40°C to +105°C MAX3490AEGSA+ Full 20Mbps 8 SO S8+4 -40°C to +105°C MAX3491AEASD+ Full 20Mbps 14 SO S14+1 -40°C to +125°C +Denotes lead(Pb)-free/RoHS-compliant package. *EP = Exposed paddle. www.maximintegrated.com Maxim Integrated │ 18 MAX3483AE/MAX3485AE/ MAX3488AE/MAX3490AE/ MAX3491AE +3.3V-Powered, ±20kV ESD-Protected, 20Mbps and Slew-Rate-Limited RS-485/RS-422 Transceivers Revision History REVISION NUMBER REVISION DATE 0 3/16 DESCRIPTION Initial release PAGES CHANGED — For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim Integrated’s website at www.maximintegrated.com. Maxim Integrated cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim Integrated product. No circuit patent licenses are implied. Maxim Integrated reserves the right to change the circuitry and specifications without notice at any time. The parametric values (min and max limits) shown in the Electrical Characteristics table are guaranteed. Other parametric values quoted in this data sheet are provided for guidance. Maxim Integrated and the Maxim Integrated logo are trademarks of Maxim Integrated Products, Inc. © 2015 Maxim Integrated Products, Inc. │ 19