Interface & Connectivity

Overview

Description

These devices are BiCMOS interface ICs that are user configured as either a single RS-422, RS-485 differential transceiver, or as a dual (2 Tx, 2 Rx) RS-232 transceiver. In RS-232 mode, the on-board charge pump generates RS-232 compliant ±5V Tx output levels, from a supply as low as 4.5V. Four small 0.1µF capacitors are required for the charge pump. The transceivers are RS-232 compliant, with the Rx inputs handling up to ±25V, and the Tx outputs handling ±12V. In RS-485 mode, the transceivers support both the RS-485 and RS-422 differential communication standards. The RS-485 receiver features full fail-safe operation, so the Rx output remains in a high state if the inputs are open or shorted together. The RS-485 transmitter supports up to three data rates, two of which are slew rate limited for problem-free communications. The charge pump disables in RS-485 mode, thereby saving power, minimizing noise and eliminating the charge pump capacitors. Both RS-232, RS-485 modes feature loopback and shutdown functions. The loopback mode internally connects the Tx outputs to the corresponding Rx input, which facilitates the implementation of board level self-test functions. The outputs remain connected to the loads during loopback, so connection problems (e. g., shorted connectors or cables) can be detected. The shutdown mode disables the Tx and Rx outputs, disables the charge pump if in RS-232 mode, and places the IC in a low current (35µA) mode. The ISL41387 is a QFN packaged device that offers additional functionality, including a lower speed and edge rate option (115kbps) for EMI sensitive designs, or to allow longer bus lengths. It also features a logic supply voltage pin (VL) that sets the VOH level of logic outputs, and the switching points of logic inputs, to be compatible with another supply voltage in mixed voltage systems. The QFN's choice of active high or low Rx enable pins increases design flexibility, allowing Tx/Rx direction control via a single signal by connecting DEN and RXEN together. For a dual port version of these devices, please see the ISL81334, ISL41334 datasheet.

Features

  • 5V powered, user selectable RS-232 or RS-485, RS-422 interface port (two RS-232 transceivers or one RS-485, RS-422 transceiver)
  • ±15kV (HBM) ESD protected bus pins (RS-232 or RS-485)
  • True flow-through pinouts simplify board layouts
  • Pb-Free (RoHS compliant)
  • Large (2.7V) differential VOUT for improved noise immunity in RS-485, RS-422 networks
  • Full fail-safe (open/short) Rx in RS-485, RS-422 mode
  • Loopback mode facilitates board self test functions
  • User selectable RS-485 data rates: 20Mbps
  • Slew rate limited: 460kbps
  • Slew rate limited (ISL41387 only): 115kbps
  • Fast RS-232 data rate: up to 650kbps
  • Low current shutdown mode: 35µA
  • QFN package saves board space (ISL41387 only)
  • Logic supply pin (VL) eases operation in mixed supply systems (ISL41387 only)

Applications

  • Gaming applications (eg, slot machines)
  • Single board computers
  • Factory automation
  • Security networks
  • Industrial/Process control networks
  • Level translators (eg, RS-232 to RS-422)
  • Point of sale (POS) equipment

Documentation

Title Type Date
PDF1.61 MB
Datasheet
PDF207 KB
Application Note
PDF352 KB
Application Note
PDF474 KB
Application Note
PDF366 KB
Application Note
PDF178 KB
Application Note
PDF513 KB
Application Note
PDF826 KB
Application Note
PDF443 KB
Application Note
PDF582 KB
Application Note
PDF440 KB
Application Note
PDF338 KB
Application Note
PDF365 KB
Application Note
PDF375 KB
Application Note
PDF339 KB
Application Note
Brochure
PDF2.72 MB日本語
Brochure
PDF156 KB
Other
PDF253 KB
Other
PDF359 KB
Other
PDF580 KB
Other
PDF326 KB
Product Change Notice
PDF398 KB
Product Change Notice
PDF222 KB
Product Change Notice
PDF106 KB
Product Change Notice
PDF173 KB
Product Change Notice
PDF438 KB
Report
PDF188 KB
Technical Brief
PDF300 KB
Technical Brief
PDF328 KB
Technical Brief
PDF920 KB 简体中文
White Paper

Design & Development

Boards & Kits

Boards & Kits

Models