SP3077EEN ±15kV IC Chip ESD-Protected 3.3V 1/8 Load Failsafe RS-485/RS422 Transceivers

±15kV ESD-Protected, 3.3V, 1/8 Load, Failsafe

RS-485/RS422 Transceivers

Features

■ ±15kV ESD protection for RS485 pins

■ 3.3V low-power operation

■ Advanced Receiver-failsafe protection for open, shorted or terminated lines

■ Up to 256 Transceivers may share Bus

■ Very low load for 8x greater fanout

■ Hot Swap glitch protection RE and DE

■ Thermal shutdown protects against driver contention

■ Available in three industry standard footprints

■ SP3070E, 3073 and 3076 in Full-Duplex (14 pin)

■ SP3071E, 3074 and 3077 in Full-Duplex (8 pin)

■ SP3072E, 3075 and 3078 in Half-Duplex (8 pin)

■ Three applications-optimized speed grades

■ SP3070E-72E: 250kbps slew-limited

■ SP3073E-75E: 500kbps slew-limited

■ SP3076E-78E: 16Mbps high speed

■ Small form factor SO-narrow packages

■ Industrial (-40 to +85ºC) and Extended (-40 to +125ºC) temperature grades

DESCRIPTION

The SP3070E-3078E differential line transceivers are suitable for bidirectional communication on balanced multipoint bus transmission lines and comply with both RS485 and RS422 EIA Standards. Each device consists of a differential driver and differential receiver. All devices operate from a 3.3V power supply.

  High receiver input impedance allows a large number of transceivers to share a common data bus while maintaining signal margin and without excessive loading or use of expensive repeaters. The high impedance driver output is maintained over the entire common-mode voltage range from -7 to +12V. Receivers will failsafe to logic 1 output when inputs are open, shorted or terminated. Drivers include built-in short-circuit protection and a thermal-overload shutdown to protect against excessive power dissipation from bus contention or cable faults. All RS485 receiver inputs and driver outputs are ESD protected up to ±15kV (Air-Gap and Human Body Model) and up to ±8kV Contact discharge (IEC 1000-4-2).

DETAILED DESCRIPTION

The SP307XE family of high speed transceivers for RS-485/RS-422 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 SP3070E, SP3072E, SP3073E, SP3075E, SP3076E and SP3078E also feature a hotswap capability allowing live insertion without error data transfer. The SP3070E, SP3071E and SP3072E feature reduced slew-rate drivers that minimize EMI and reduce reflections caused by improperly terminated cables, allowing error-free data transmission up to 250kbps. The SP3073E, SP3074E and SP3075E also offer slew -rate limits allowing transmit speeds up to 500kbps. The SP3076E, SP3077E, SP3078E driver slew rates are not limited, making transmit speeds up to 16Mbps possible. The SP3072E, SP3075E and SP3078E are half-duplex transceivers, while the SP3070E, SP3071E, SP3073E, SP3074E, SP3076E, and SP3077E are full duplex transceivers. All devices operate from a single 3.3V 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 highimpedance state.