LTM2881 - Completed Isolated RS485/RS422 µModule ...

1 LTM2881 . Complete Isolated RS485/RS422 Module Transceiver + Power Features Description nn RS485/RS422 Transceiver: 2500 VRMS for 1 Minute The LTM 2881 is a complete galvanically Isolated full-du- nn UL-CSA Recognized File #E151738 plex RS485/RS422 Module (micromodule) transceiver. nn CSA Component Acceptance Notice 5A No external components are required. A single supply nn Isolated DC Power: 5V at Up to 200mA powers both sides of the interface through an integrated, nn No External Components Required Isolated , low noise, efficient 5V output DC/DC converter. nn 20 Mbps or Low EMI 250kbps Data Rate nn High ESD: 15kV HBM on Transceiver Interface Coupled inductors and an isolation power transformer nn High Common Mode Transient Immunity: 30kV/ s provide 2500 VRMS of isolation between the line transceiver nn Integrated Selectable 120 Termination and the logic interface. This device is ideal for systems nn ( LTM2881 -3) or ( LTM2881 -5) Operation where the ground loop is broken allowing for large com- nn to Logic Supply Pin for Flexible Digital Interface mon mode voltage variation.

2 Uninterrupted communica- nn Maximum Continuous Working voltage : 560V. tion is guaranteed for common mode transients greater PEAK than 30kV/ s. nn High Input Impedance Failsafe RS485 Receiver nn current Limited drivers and Thermal Shutdown Maximum data rates are 20 Mbps or 250kbps in slew nn Compatible with TIA/EIA-485-A and PROFIBUS limited mode. Transmit data, DI and receive data, RO, are nn High Impedance output During Internal Fault Condition implemented with event driven low jitter processing. The nn Low current Shutdown Mode (< 10 A) receiver has a one-eighth unit load supporting up to 256. nn General Purpose CMOS Isolated Channel nodes per bus. A logic supply pin allows easy interfacing nn 15mm BGA and LGA Packages with different logic levels from to , independent of the main supply. Applications Enhanced ESD protection allows this part to withstand up nn Isolated RS485/RS422 Interface to 15kV (human body model) on the transceiver interface nn industrial Networks pins to Isolated supplies and 10kV through the isolation nn Breaking RS485 Ground Loops barrier to logic supplies without latch-up or damage.

3 Nn Isolated PROFIBUS-DP Networks L, LT, LTC, LTM, Linear Technology, the Linear logo and Module are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Typical Application Isolated Half-Duplex RS485 Module Transceiver LTM2881 Operating Through 35kV/ s CM Transients ( LTM2881 -3). 5V ( LTM2881 -5) MULTIPLE SWEEPS. OF COMMON MODE. TRANSIENTS. VCC LTM2881 VCC2 5V AVAILABLE current : 500V/DIV. PWR 150mA ( LTM2881 -5). VL A 100mA ( LTM2881 -3). RO. ISOLATION BARRIER. B DI. RE RO. TWISTED-PAIR 1V/DIV. TE CABLE. DE. Y 1V/DIV. DI. Z 50ns/DIV 2881 TA01a GND GND2. 2881 TA01. 2881fi For more information 1. LTM2881 . Absolute Maximum Ratings Pin Configuration (Note 1). TOP VIEW. VCC to to 6V. VCC2 to to 6V 1 2 3 4 5 6 7 8. VL to to 6V A. DOUT TE DI DE RE RO VL ON. Interface Voltages B. (A, B, Y, Z) to VCC2 15V to 15V C GND VCC. (A-B) with Terminator 6V D.

4 Signal Voltages ON, RO, DI, DE, E. RE, TE, DOUT to to VL + F. Signal Voltages SLO, G. DIN to to VCC2 + H. Operating Temperature Range J GND2. 0 C to 70 C K. 40 C to 85 C L. DIN SLO Y. 40 C to 105 C Z B A VCC2. 55 C to 105 C BGA PACKAGE. 32-PIN (15mm ). LGA PACKAGE. 32-PIN (15mm ). Maximum Internal Operating 125 C TJMAX = 125 C, TJMAX = 125 C, JA = C/W, JA = C/W, Storage Temperature 55 C to 150 C JCTOP = C/W, JCTOP = C/W, JCBOTTOM = C/W, JCBOTTOM = C/W, Peak Package Body Reflow 245 C JB = C/W, JB = C/W, WEIGHT = 1g WEIGHT = 1g 2881fi 2 For more information LTM2881 . Order Information #orderinfo INPUT PART MARKING PACKAGE MSL. PART NUMBER voltage PAD OR BALL FINISH DEVICE FINISH CODE TYPE RATING TEMPERATURE RANGE. LTM2881CY-3#PBF 0 C to 70 C. LTM2881IY-3#PBF SAC305 (RoHS) e1 40 C to 85 C. LTM2881HY-3#PBF 40 C to 105 C. 3V to LTM2881Y-3. LTM2881HY-3 SnPb (63/37) e0 40 C to 105 C. LTM2881 MPY-3#PBF SAC305 (RoHS) e1 55 C to 105 C.

5 LTM2881 MPY-3 SnPb (63/37) e0 55 C to 105 C. BGA. LTM2881CY-5#PBF 0 C to 70 C. LTM2881IY-5#PBF SAC305 (RoHS) e1 40 C to 85 C. LTM2881HY-5#PBF 40 C to 105 C. to LTM2881Y-5 3. LTM2881HY-5 SnPb (63/37) e0 40 C to 105 C. LTM2881 MPY-5#PBF SAC305 (RoHS) e1 55 C to 105 C. LTM2881 MPY-5 SnPb (63/37) e0 55 C to 105 C. LTM2881CV-3#PBF 0 C to 70 C. LTM2881IV-3#PBF 3V to LTM2881V-3 40 C to 85 C. LTM2881HV-3#PBF 40 C to 105 C. Au (RoHS) e4 LGA. LTM2881CV-5#PBF 0 C to 70 C. LTM2881IV-5#PBF to LTM2881V-5 40 C to 85 C. LTM2881HV-5#PBF 40 C to 105 C. Device temperature grade is indicated by a label on the shipping Recommended BGA and LGA PCB Assembly and Manufacturing container. Procedures: Pad or ball finish code is per IPC/JEDEC J-STD-609. LGA and BGA Package and Tray Drawings: Terminal Finish Part Marking: This product is moisture sensitive. For more information, go to: This product is not recommended for second side reflow.

6 For more information, go to: 2881fi For more information 3. LTM2881 . Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. LTM2881 -3 VCC = , LTM2881 -5 VCC = , VL = , GND = GND2. = 0V, ON = VL unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS. Power Supply VCC VCC Supply voltage LTM2881 -3 l V. LTM2881 -5 l V. VL VL Supply voltage l V. ICCPOFF VCC Supply current in Off Mode ON = 0V l 0 10 A. ICCS VCC Supply current in On Mode LTM2881 -3 DE = 0V, RE = VL , No Load l 20 30 mA. LTM2881 -5 DE = 0V, RE = VL , No Load l 15 25 mA. VCC2 Regulated VCC2 output voltage , LTM2881 -3 DE = 0V, RE = VL , ILOAD = 100mA l V. Loaded LTM2881 -5 DE = 0V, RE = VL , ILOAD = 150mA l V. LTM2881 -3, H/MP-Grade, I LOAD = 90mA l V. VCC2 NOLOAD Regulated VCC2 output voltage , DE = 0V, RE = VL , No Load V.

7 No Load Efficiency ICC2 = 100mA, LTM2881 -5 (Note 2) 62 %. ICC2S VCC2 Short-Circuit current DE = 0V, RE = VL , VCC2 = 0V 200 mA. Driver |VOD| Differential Driver output voltage R = (Figure 1) l VCC2 V. R = 27 (RS485) (Figure 1) l VCC2 V. R = 50 (RS422) (Figure 1) l VCC2 V. |VOD| Difference in Magnitude of Driver R = 27 or R = 50 (Figure 1) l V. Differential output voltage for Complementary output States VOC Driver Common Mode output R = 27 or R = 50 (Figure 1) l 3 V. voltage |VOC| Difference in Magnitude of Driver R = 27 or R = 50 (Figure 1) l V. Common Mode output voltage for Complementary output States IOZD Driver Three-State (High DE = 0V, (Y or Z) = 7V, +12V l 10 A. Impedance) output current on DE = 0V, (Y or Z) = 7V, +12V, H/MP-Grade l 50 A. Y and Z. IOSD Maximum Driver Short-Circuit 7V (Y or Z) 12V (Figure 2) l 250 250 mA. current Receiver RIN Receiver Input Resistance RE = 0V or VL , VIN = 7V, 3V, 3V, 7V, 12V (Figure 3) l 96 125 k.

8 RE = 0V or VL , VIN = 7V, 3V, 3V, 7V, 12V (Figure 3), l 48 125 k . H/MP-Grade RTE Receiver Termination Resistance TE = VL , VAB = 2V, VB = 7V, 0V, 10V (Figure 8) l 108 120 156 . Enabled IIN Receiver Input current (A, B) ON = 0V VCC2 = 0V or 5V, VIN = 12V (Figure 3) l 125 A. ON = 0V VCC2 = 0V or 5V, VIN = 12V (Figure 3), H/MP-Grade l 250. ON = 0V VCC2 = 0V or 5V, VIN = 7V (Figure 3) l 100 A. ON = 0V VCC2 = 0V or 5V, VIN = 7V (Figure 3), H/MP-Grade l 145. VTH Receiver Differential Input 7V B 12V l V. Threshold voltage (A-B). VTH Receiver Input Failsafe Hysteresis B = 0V 25 mV. Receiver Input Failsafe Threshold B = 0V 0 V. 2881fi 4 For more information LTM2881 . Electrical Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. LTM2881 -3 VCC = , LTM2881 -5 VCC = , VL = , GND = GND2. = 0V, ON = VL unless otherwise noted.

9 SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS. Logic VIL Logic Input Low voltage VL l V. VIH DIN l VCC2 V. SLO l 2 V. Logic Input High voltage DI, TE, DE, ON, RE: VL l VL V. VL < l VL V. IINL Logic Input current l 0 1 A. VHYS Logic Input Hysteresis (Note 2) 150 mV. VOH output High voltage output High, ILOAD = 4mA l VL V. (Sourcing), VL 3V. output High, ILOAD = 1mA l VL V. (Sourcing), VL < 3V. VOL output Low voltage output Low, ILOAD = 4mA l V. (Sinking), VL 3V. output High, ILOAD = 1mA l V. (Sinking), VL < 3V. IOZR Three-State (High Impedance) RE = VL , 0V RO VL l 1 A. output current on RO. IOSR Short-Circuit current 0V (RO or DOUT) VL l 85 mA. Switching Characteristics The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25 C. LTM2881 -3 VCC = , LTM2881 -5 VCC = , VL = , GND = GND2. = 0V, ON = VL unless otherwise noted.

10 SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS. Driver SLO = VCC2. fMAX Maximum Data Rate (Note 3) 20 Mbps tPLHD Driver Input to output RDIFF = 54 , CL = 100pF l 60 85 ns tPHLD (Figure 4). tPD Driver Input to output Difference RDIFF = 54 , CL = 100pF l 1 8 ns |tPLHD tPHLD| (Figure 4). tSKEWD Driver output Y to output Z RDIFF = 54 , CL = 100pF l 1 8 ns (Figure 4). tRD Driver Rise or Fall Time RDIFF = 54 , CL = 100pF l 4 ns tFD (Figure 4). tZLD , tZHD , Driver output Enable or Disable RL = 500 , CL = 50pF l 170 ns tLZD , tHZD Time (Figure 5). Driver SLO = GND2. fMAX Maximum Data Rate (Note 3) 250 kbps tPLHD Driver Input to output RDIFF = 54 , CL = 100pF 1 s tPHLD (Figure 4). tPD Driver Input to output Difference RDIFF = 54 , CL = 100pF 50 500 ns |tPLHD tPHLD| (Figure 4). tSKEWD Driver output Y to output Z RDIFF = 54 , CL = 100pF 200 500 ns (Figure 4). tRD Driver Rise or Fall Time RDIFF = 54 , CL = 100pF l s tFD (Figure 4).