Features: 3.3V Operation
Electrostatic Discharge (ESD) Protection for
RS-485 I/O Pins
±15kV Human Body Model
True Fail-Safe Receiver While Maintaining
EIA/TIA-485 Compatibility
Hot-Swap Input Structure on DE and RE
Enhanced Slew-Rate Limiting Facilitates Error-
Free Data Transmission
(MAX3070EMAX3075E/MAX3079E)
Low-Current Shutdown Mode (Except
MAX3071E/MAX3074E/MAX3077E)
Pin-Selectable Full-/Half-Duplex Operation
(MAX3079E)
Phase Controls to Correct for Twisted-Pair
Reversal (MAX3079E)
Allow Up to 256 Transceivers on the Bus
Available in Industry-Standard 8-Pin SO PackageApplicationLighting Systems
Industrial Control
Telecom
Security Systems
InstrumentationPinout
Specifications(All voltages referenced to GND)
Supply Voltage (VCC)...............................................................+6V
Control Input Voltage (RE, DE, SLR,
H/F, TXP, RXP)............................................................-0.3V to +6V
Driver Input Voltage (DI)............................................-0.3V to +6V
Driver Output Voltage (Z, Y, A, B)................................-8V to +13V
Receiver Input Voltage (A, B).......................................-8V to +13V
Receiver Input Voltage
Full Duplex (A, B).........................................................-8V to +13V
Receiver Output Voltage (RO).........................-0.3V to (VCC+ 0.3V)
Driver Output Current.......................................................±250mA
Continuous Power Dissipation (TA= +70°C)
8-Pin SO (derate 5.88mW/°C above +70°C)......................471mW
8-Pin Plastic DIP (derate 9.09mW/°C above +70°C)..........727mW
14-Pin SO (derate 8.33mW/°C above +70°C)....................667mW
14-Pin Plastic DIP (derate 10.0mW/°C above +70°C)........800mW
Operating Temperature Ranges
MAX307_EE_ _......................................................-40°C to +85°C
MAX307_EA_ _....................................................-40°C to +125°C
Junction Temperature........................................................+150°C
Storage Temperature Range...............................-65°C to +150°C
Lead Temperature (soldering, 10s)....................................+300°C
DescriptionThe MAX3070EMAX3079E 3.3V, ±15kV ESD-protected, RS-485/RS-422 transceivers feature one driver and one receiver. These devices include fail-safe circuitry, guar- anteeing a logic-high receiver output when receiver inputs are open or shorted. The receiver outputs a logic high if all transmitters on a terminated bus are disabled (high impedance). The MAX3070EMAX3079E include a hot-swap capability to eliminate false transitions on the bus during power-up or hot insertion.
The MAX3070E/MAX3071E/MAX3072E feature reduced slew-rate drivers that minimize EMI and reduce reflec- tions caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The MAX3073E/MAX3074E/MAX3075E also feature slew- rate-limited drivers but allow transmit speeds up to 500kbps. The MAX3076E/MAX3077E/MAX3078E driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The MAX3079E slew rate is pin selectable for 250kbps, 500kbps, and 16Mbps.
The MAX3072E/MAX3075E/MAX3078E are intended for half-duplex communications, and the MAX3070E/ MAX3071E/MAX3073E/MAX3074E/MAX3076E/MAX307 7E are intended for full-duplex communications. The MAX3079E is selectable for half-duplex or full-duplex operation. It also features independently programmable receiver and transmitter output phase through separate pins.
The MAX3070EMAX3079E transceivers draw800 µAofsupply current when unloaded or when fullyloaded with the driversd isabled.Alldeviceshavea1/8-unit load receiver input impedance, allowing up to 256 transceivers on the bus.
MAX3071 Data Sheet
