CBM485

CBM485AS COREBAI | Alldatasheet

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Technical content

www.corebai.com CBM485AS OPERATION INSTRUCTION

FEATURES

 Low Quiescent Current: 300µA  -7V to +12V Common-Mode Input Voltage Range  Three-State Outputs  50ns Propagation Delays, 5ns Skew  Half-Duplex Version Available  Operate from a Single 5V Supply  Allows up to 32 Transceivers on the Bus  Data rate: 10 Mbps  Current-Limiting and Thermal Shutdown for Driver Overload Protection  Enhanced ESD Specifications:  ±15kV IEC61000-4-2 Air Discharge  ±8kV IEC61000-4-2 Contact Discharge

APPLICATIONS

 Low power RS-485 systems  DTE/DCE interface  Packet switching  Local area networks (LNAs)  Data multiplexers  Data concentration  Integrated services digital network (ISDN) GENERAL DESCRIPTION The CBM485 is low-power transceivers for RS-485 and RS-422 communication. IC contains one driver and one receiver. The driver slew rates of the CBM485 is not limited, allowing them to transmit up to 10 Mbps. These transceivers draw between 120µA and 500µA of supply current when unloaded or fully loaded with disabled drivers. All parts operate from a single 5V supply. Drivers are short-circuit current limited and are protected against excessive power dissipation by thermal shutdown circuitry that places the driver outputs into a high-impedance state. The receiver input has a fail-safe feature that guarantees a logic-high output if the input is open circuit. The CBM485 is designed for half-duplex applications. A ll data sheet.com

www.corebai.com CBM485AS OPERATION INSTRUCTION Pin Description ABSOLUTE MAXIMUM RATINGS Supply Voltage (V CC) 12V Continuous Power Dissipation (T A= +70℃) Control Input Voltage -0.5V to (V CC + 0.5V) 8-Pin Plastic DIP (derate 9.09mW/°C above +70℃) 727mW Driver Input Voltage (DI) -0.5V to (V CC+ 0.5V) 8-Pin SOP (derate 5.88mW/℃ above +70℃) 471mW Driver Output Voltage (A, B) -8V to +12.5V Operating Temperature Ranges -40℃ to +85℃ Receiver Input Voltage (A, B) -8V to +12.5V Storage Temperature Range -65℃ to +160℃ Receiver Output Voltage (RO) -0.5V to (V CC+0.5V) Lead Temperature (soldering, 10sec) +300℃ * 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 under “recommended operating conditions” is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability. A ll data sheet.com

www.corebai.com CBM485AS OPERATION INSTRUCTION DC ELECTRICAL CHARACTERISTICS (VCC = 5V ±5%, T A = TMIN to TMAX, unless otherwise noted.) (Notes 1, 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Differential Driver Output (no load) VOD1 5 V Differential Driver Output (with load) VOD2 R = 50Ω (RS-422) 2 V R = 27Ω (RS-485), Figure 1 1.5 5 Change in Magnitude of Driver Differential Output Voltage for Complementary Output States ∆VOD R = 27Ω or 50Ω, Figure 1 0.2 V Driver Common-Mode Output Voltage VOC R = 27Ω or 50Ω, Figure 1 3 V Change in Magnitude of Driver Common-Mode Output Voltage for Complementary Output States ∆VOC R = 27Ω or 50Ω, Figure 1 0.2 V Input High Voltage VIH DE, DI, RE 2.0 V Input Low Voltage VIL DE, DI, RE 0.8 V Input Current IIN1 DE, DI, RE ±2 μA Input Current (A, B) IIN2 DE = 0V; VCC = 0V or 5.25V VIN = 12V 1.0 mA VIN = -7V -0.8 Receiver Differential Threshold Voltage VTH -7V ≤ V CM ≤12V -0.2 0.2 V Receiver Input Hysteresis ∆VTH VCM = 0V 70 mV Receiver Output High Voltage VOH IO = -4mA, VID = 200mV 3.5 V Receiver Output Low Voltage VOL IO = 4mA, VID = -200mV 0.4 V Three-State (high impedance) Output Current at Receiver IOZR 0.4V ≤ V O ≤ 2.4V ±1 μA Receiver Input Resistance RIN -7V ≤ V CM ≤ 12V 12 kΩ No-Load Supply Current (Note 3) ICC DE = V CC 500 900 μARE = 0V or V CC 300 500 DE = 0V Driver Short-Circuit Current IOSD1 -7V ≤ V O ≤ 12V (Note 4) 35 250 mA VO = High Driver Short-Circuit Current IOSD2 -7V ≤ V O ≤12V (Note 4) 35 250 mA VO = Low Receiver Short-Circuit Current IOSR 0V ≤ V O ≤ VCC 7 95 mA ESD Protection A, B, Y and Z pins, tested using Human Body Model 15 kV A ll data sheet.com

www.corebai.com CBM485AS OPERATION INSTRUCTION SWITCHING CHARACTERISTICS (VCC = 5V ±5%, TA = TMIN to TMAX, unless otherwise noted.) (Notes 1, 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Driver Input to Output tPLH RDIFF = 54 10 55 60 ns tPHL CL1 = CL2 = 100pF 10 55 60 Driver Output Skew to Output tSKEW RDIFF = 54 , C L1 = CL2 = 100pF 5 10 ns Driver Enable to Output High tZH CL= 100pF, S2 closed 40 70 ns Driver Enable to Output Low tZL CL= 100pF, S1 closed 40 70 ns Driver Disable Time from Low tLZ CL= 15pF, S1 closed 40 70 ns Driver Disable Time from High tHZ CL= 15pF, S2 closed 40 70 ns Receiver Input to Output tPLH RDIFF = 54 CL1 = CL2 = 100pF 20 60 100 ns tPHL 20 60 100 | tPLH - tPHL | Differential Receiver Skew tSKD RDIFF = 54 CL1 = CL2 = 100pF 5 10 ns Receiver Enable to Output Low tZL CRL = 15pF, S1 closed 30 50 ns Receiver Enable to Output High tZH CRL = 15pF, S2 closed 30 50 ns Receiver Disable Time from Low tLZ CRL = 15pF, S1 closed 30 50 ns Receiver Disable Time from High tHZ CRL = 15pF, S2 closed 30 50 ns Maximum Data Rate fMAX 2.5 10 20 Mbps Note 1: All currents into device pins are positive; all currents out of device pins are negative. All voltages are referenced to device ground unless otherwise specified. Note 2: All typical specifications are given for V CC=5V and T A=+25℃. Note 3: Supply current specification is valid for loaded transmitters when DE=0V. Note 4: Applies to peak current. A ll data sheet.com

Figure 10. CBM485 Typical RS-485 Network

www.corebai.com CBM485AS OPERATION INSTRUCTION Driver Output Protection Excessive output current and power dissipation caused by faults or by bus contention are prevented by two mechanisms. A foldback current limit on the output stage provides immediate protection against short circuits over the whole common-mode voltage range. In addition, a thermal shutdown circuit forces the driver outputs into a high-impedance state if the die temperature rises excessively. Propagation Delay Skew time is simply the difference between the low-to-high and high-to-low propagation delay. Small driver/receiver skew times help maintain a symmetrical mark-space ratio (50% duty cycle). The receiver skew time, |t PRLH - t PRHL|, is under 10ns. The driver skew times are 5ns for the CBM485. Typical Applications CBM485 transceivers are designed for bidirectional data communications on multipoint bus transmission lines. Figure 10 shows typical network applications circuits. These parts can also be used as line repeaters, with cable lengths longer than 4000 feet. 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. A ll data sheet.com

www.corebai.com CBM485AS OPERATION INSTRUCTION PACKAGE NOTES: 1. Dimensions A and B do not include mold flash or protrusion. 2. Maximum mold flash or protrusion 0.15 mm (0.006) per side for A; for B ‑ 0.25 mm (0.010) per side. Symbol Dimensions ,mm Min Max A 4.8 5 B 3.8 4 C 1.35 1.75 D 0.33 0.51 F 0.4 1.27 G 1.27 H 5.72 J 0° 8° K 0.1 0.25 M 0.19 0.25 P 5.8 6.2 R 0.25 0.5 A ll data sheet.com

www.corebai.com CBM485AS OPERATION INSTRUCTION PACKAGE/ORDERING INFORMATION PRODUCT ORDERING NUMBER TEMPRANGE PACKAGE PAKEAGE MARKING TRANSPOT MEDIA,QUANTILY CBM485 CBM485AS -40℃~85℃ SOIC-8(SOP8) CBM485A Tape and Reel,2500 CBM485ACS -0℃~70℃ SOIC-8(SOP8) CBM485C Tape and Reel,2500 A ll data sheet.com