Each driver output and receiver input is protected against electrostatic discharge up to 15 kv and has no latchup. The ltc2872 can be configured as four rs232 singleended transceivers or two rs485 differential transceivers, or combinations. Rs422 can interoperate with interfaces designed to milstd188114b, but they are not identical. All drivers can be slew limited to 250kbps in any mode to minimize electromagnetic interference emi. Amd 26ls33pc quad differential line receiver for sale.
It will happily feed a rs 485 device so long as that rs 485 device is only ever receiving data. However one driver can fanout to up to ten receivers. Rs 422 dual differential line driver and receiver pairs general description the ds892222a and ds8923a are dual differential line driver and receiver pairs. The max14891e quad faultprotected rs485rs422 receiver is ideal for applications requiring high. Each driver and receiver has separate input and output pins for fullduplex bus communication designs. The lowpower, highspeed transceivers of this family are designed for rs 485, rs 422 and rs 423 communication applications. The device contains one differential transceiver consisting of a line driver and receiver. February 2008 rev 5 117 17 st490ab low power high speed rs485rs422 transceiver features low supply current. The rs485 specification meets the requirements for a truly multipoint communications network, and the standard specifies up to 32 drivers and 32 receivers on. Low power rs485rs422 transceiver stmicroelectronics. These transceivers support data rates of 115kbps, 1mbps, and 20mbps. Several key advantages offered by this standard include the differential receiver, a differential driver and data rates as high as 10 megabits per second at 12. Yes, rs422 and rs485 always need a commonground reference for proper communications.
These devices feature failsafe circuitry, which guarantees a logichigh receiver output when the receiver inputs are open or shorted. An integrated dcdc powers the cableside of the module. These monolithic quadruple differential line drivers with 3state outputs are designed to meet the requirements of ansi standards eiatia 422 b and rs 485 and itu recommendation v. The boards i see for rs 422 have one differential transmit and 1 receive line. The max22502e fullduplex, esdprotected, rs 485 rs 422 transceiver is optimized for highspeed up to 100mbps communication over long cables. In addition, the devices meet the requirements of the eia standard rs 422. Esdprotected rs 485 transceivers feature one driver and one receiver. Maxim offers over 160 rs485rs422 transceivers for applications such as automotive, hvac, metering, and point of sale pos. Images could represent a series that may have multiple options e. The range of the common mode voltage vcm that the driver. Ltc2872 rs232rs485 dual multiprotocol transceiver with. Using an lvds receiver with tiaeia 422 data when ground noise between the transmitter and receiver is less than 1 v, figure 1 denotes a circuit that uses a resistor divider circuit in front of the lvds receiver that attenuates the 422 differential signal to lvds levels. A receiver input resistance of approximately 12k the standard allows up to 32 one unit load devices on the bus, and the load from each device tx or rx must be. These devices include failsafe circuitry, guaranteeing a logichigh receiver output when receiver inputs are open or shorted.
Atc840 usb to rs422 converter at rs 2100 piece usb. The sn65hvd379 is a differential line driver and differentialinput line receiver that operates with a 3. Rs 485 incorporates the specifications of the pointtopoint rs 422 standard but is more robust, which makes the rs 485 ideal for industrial applications. Rs 422 key parameters and topology rs 422 is a unidirectional, multidrop network, allowing for the use of a single driver with an output signal that can be dropped at multiple up to 10 receiver nodes see figure1. The isl315xe family includes half and fullduplex transceivers with activehigh driver enable pins and activelow receiver enable pins. As many as 32 driver receiver pairs can share a multidrop network. All driver outputs and receiver inputs are protected. They usually contain one driver and one receiver in half duplex configuration. Using the hs 26ct32rh radiation hardened rs 422linereceiver application note an9520rev 4. Maxim offers a complete portfolio of interface devices. The receiver outputs a logichigh if all transmitters on a terminated bus are disabled high impedance. How to design and layout an emioptimized pcb for the.
The maxm22510 and maxm22511 isolated rs 485 rs 422, fullduplex, transceiver modules provide 2500vrms 60s of galvanic isolation between the cableside rs 485 rs 422 driver receiver side and the uartside of the device. Rs 422 was designed for greater distances and higher baud rates than rs232. Rs422 uses a nominal 0 to 5 volt signal while milstd188114b uses a signal symmetric about 0 v. Max14891e quad faultprotected rs485rs422 receiver with. Data rates of up to 10m bits second and distances up to 4,000 feet can be accommodated with rs 422. Although receivers detect differential signals, equipment needs a ground return path to keep signals within the common mode range of the receivers. The main difference is that up to 32 transmitter receiver pairs may be present on the rs485 lines at one time. Max22502e 100mbps fullduplex rs485rs422 transceiver. How to properly configure and wire rs422 and rs485. Rs 485 transceivers are available in both industrystandard packages and small, spacingsaving packages. The part contains two rs232 drivers, one rs422 driver, one rs232 receiver, and one receiver path which can be configured either as rs232 or as rs422. So16 rs422 interface ic, am26ls32a rs422 interface ic, receiver so16 smdsmt 4 receiver 5. Rs422, rs485 differential line driver texas instruments. Need a discrete configurable rs422 driver io board for.
Rs232, rs485, rs422 drivers transmitters product list at newark. Rs485multiple driver communications rs485 is similar to rs422 upon which it is based. They are made for serial communication to rs 422 devices. This means that the receiver output is a logic high if all transmitters on a terminated bus are disabled high impedance. Common mode refers to an equal voltage added to the bus signals. It meets all rs 422 specifications, but is more robust including, for example, a higher receiver input impedance and wider commonmode range 7v to. The rs 485 is a bidirectional standard that features multiple drivers and receivers on a single bus, in which each driver can relinquish or drive the bus. The high speed drivers operate up to 20mbps in rs 485 rs 422 modes, and up to 1mbps in rs232 mode. Rs422, rs485 receivers maxim integrated rs422, rs485.
This transceiver features larger receiver hysteresis for high noise rejection and improved signal integrity. Encoder link, rs 422 driver receiver rev d3, page 641 absolute maximum ratings beyond these values damage may occur. The rs 485 specification meets the requirements for a truly multipoint communications network, and the standard specifies up to 32 drivers and 32 receivers on a single 2wire bus. The device contains one driver and one receiver in full duplex configuration. Rs 422 is also specified for multidrop applications where only one driver is connected to, and transmits on, a. Designed for rs422 and rs485 networks the differential bus driver and receiver are monolithic, integrated circuits designed for fullduplex bidirectional data communication on multipoint bustransmission lines at signaling rates1 up to 25 digital motor control mbps. Rs 422 vs rs 485 similarities and key differences 1. The receiver inputs feature a full failsafe design that turns the receiver outputs high when the bus inputs are open or shorted.
Transfers per second on each rs 422 rs 485 channel the sn65hvd09 is characterized for operation over. Rs422 cannot implement a true multipoint communications network such as with eia485 since there can be only one driver on each pair of wires. Many include integrated features that reduce cost, design complexity, and board space by eliminating external components. The max487e max488e include a hotswap capability to eliminate. Analog devices offers a wide range of standard rs 485. Rs 485 is a bidirectional, halfduplex standard featuring multiple bused drivers and receivers, in which each driver can relinquish the bus. When connected to a pc usb port the atc840 module is automatically detected and is installed as a native com port which is compatible with any existing serial communication application. The atc840 module is a costeffective way to convert rs422 industrial buses to a usb interface. These devices are designed specifically for applications meeting the st506, st412 and esdi disk drive standards. You will have a data collision if the rs 485 device ever tries to transmit on that pair. I need a board with 8 differential transmit lines with rs 422 drivers basically rs 422 signal levels, differential output that i can discretely control, more like discrete io boards. Many characteristics of the drivers and receivers are the same as rs 422. The transceiver operates at data rates up to 20mbps, with an output skew of less than 6ns.