 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
SP331 Datasheet(PDF) 10 Page - Sipex Corporation |
|
||||||||||||||||||||||||||||||
SP331 Datasheet(HTML) 10 Page - Sipex Corporation |
|
|
10 / 13 page  Date: 03-04-05 Programmable Dual RS-232/RS-485 Transceiver © Copyright 2005 Sipex Corporation 10 Drivers The SP331 has four independent RS-232 single- ended drivers and two differential RS-485 driv- ers. Control for the mode selection is done via a four–bit control word. The drivers are pre- arranged such that for each mode of operation the relative position and functionality of the drivers are set up to accommodate the selected interface mode. As the mode of the drivers is changed, the electrical characteristics will change to support the requirements of clock, data, and control line signal levels. Unused driver inputs can be left floating; however, to ensure a desired state with no input signal, pull–up resistors to +5V or pull–down resistors to ground are sug- gested. Since the driver inputs are both TTL or CMOS compatible, any value resistor less than 100k Ω will suffice. When in RS-232 mode, the single-ended RS- 232 drivers produce compliant RS-232E and ITU V.28 signals. Each of the four drivers output single-ended bipolar signals in access of ±5V with a full load of 3kΩ and 2500pF applied as specified. These drivers can also operate at least 120kbps. When programmed to RS-485 mode, the differ- ential RS-485 drivers produce complaint RS- 485 signals. Each RS-485 driver outputs a uni- polar signal on each output pin with a magnitude of at least 1.5V while loaded with a worst case of 54 Ω between the driver's two output pins. The signal levels and drive capability of the RS- 485 drivers allow the drivers to also comply with RS-422 levels. The transmission rate for the differential drivers is 10Mbps. Receivers The SP331 has four single-ended receivers when programmed for RS-232 mode and two differ- ential receivers when programmed for RS-485 mode. Control for the mode selection is done via a 4– bit control word, as in the drivers. As the oper- ating mode of the receivers is changed, the electrical characteristics will change to support the requirements of the appropriate serial stan- dard. Unused receiver inputs can be left floating without causing oscillation. To ensure a desired state of the receiver output, a pull–up resistor of 100k Ω to +5V should be connected to the in- verting input for a logic low, or the non–invert- ing input for a logic high. For single-ended receivers, a pull–down resistor to ground of 5k Ω is internally connected, which will ensure a logic high output. The RS-232 receiver has a single–ended input with a threshold of 0.8V to 2.4V. The RS-232 receiver has an operating voltage range of ±15V and can receive signals up to 120kbps. RS-232 receivers are used in RS-232 mode for all signal types include data, clock, and control lines of the RS-232 serial port. The differential RS-485 receiver has an input impedance of 15k Ω and a differential threshold of ±200mV. Since the characteristics of an RS- 422 receiver are actually subsets of RS-485, the receivers for RS-422 requirements are identical to the RS-485 receivers. All of the differential receivers can receive data up to 10Mbps. Select Mode Pins Similar to our SP500 family of multiprotocol products, the SP331 has the ability to change the configuration of the drivers and receivers via a 4–bit switch. Referring to Table 1; RS-232 mode, RS-485 mode, or two different combina- tions of RS-232/RS-485 can be configured us- ing the SEL_A and SEL_B pins. The drivers can be put into tri-state mode by using the SEL_C and SEL_D pins. All receivers remain active during any tri-state condition of the driv- ers. Loopback Mode Loopback is invoked by asserting "xx11" into the select pins. In RS-232/RS-485 or RS-485/ RS-232 loopback mode, the RS-232 driver out- puts loop back into the RS-232 receiver inputs and the RS-485 differential driver loops back into the RS-485 receiver. During loopback, the driver outputs and receiver inputs are discon- nected from the outside world. The driver outputs are in tri-state and the receiver inputs are disabled. The input impedance of the receivers during loopback is approximately 15k Ω to ground. |
Similar Part No. - SP331 |
|
Similar Description - SP331 |
|
|
|
Link URL |
| Privacy Policy |
| ALLDATASHEET.NET |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
