News & Events
Intersil's ESD-Protected Fractional-Load RS-485/422 Data Transceivers Offer a Robust Alternative for Industry Standard Parts
MILPITAS, CA, November 18, 2003 Intersil Corporation (NASDAQ: ISIL), a world leader in the design and manufacture of high performance analog solutions, today announced three new ESD-protected RS-485/422 serial data transceivers, the ISL8487E, ISL81487L and ISL81487E. All three ICs are half-duplex fractional-load transceivers that operate from a nominal 5-V supply over a wide +/-10% tolerance voltage range of +4.5 to +5.5 V, which relaxes supply requirements and reduces costs. The greater than +/-15 kV ESD protection on all Rx and Tx pins ensures robustness for reliable operation in applications where electrostatic voltage discharged into plugs and jacks by human contact poses a reliability threat. This ESD-protected family also offers very low quiescent current, extremely low shutdown current and less bus loading with lower input current than competing ICs that they replace.
The ISL8487E, ISL81487L and ISL81487E are eighth-unit-load transceivers that increase the number of devices allowed on the bus up to 256 from the traditional single unit load limit of 32. This eliminates the need for repeaters in large data-collecting or control networks. Applications for these fractional-load transceivers include, but are not limited to, factory automation, security networks, process control, plant environmental control and remote sensing and metering.
The ISL8487E and ISL81487L are slew-rate limited for error free data transmission in applications where the data rate is less than 250 kbps, typically used for long data-collecting networks, up to 4,000 feet. Slew-rate limiting reduces EMI and minimizes reflections from improperly terminated transmission lines, or unterminated stubs in multi-drop and multipoint applications. The ISL81487E can operate up to 5 Mbps for high-speed applications over shorter networks.
All three ICs are half-duplex transceivers whose receive (Rx) and transmit (Tx) functions are multiplexed, reducing package size and pin count to only 8-leads. Rx inputs feature a fail-safe-if-open design, which ensures a logic high Rx output if Rx inputs are floating. This prevents the Rx output from chattering, and accidentally generating interrupts, if the receiver becomes disconnected from the bus. A "lock-out" feature keeps the Rx output disabled, when exiting shutdown, until the Rx has determined what state it should go to. This prevents the Rx output from accidentally generating an interrupt while the Rx wakes up. Driver outputs are short circuit protected, even for voltages that exceed the supply voltage. Additionally, on-chip thermal shutdown circuitry disables the Tx outputs to prevent damage if power dissipation becomes excessive.
ISL8487E, ISL81487L and ISL81487E Technical Details
- Greater than +/-15 kV ESD protection on Rx and Tx pins, greater than 7 kV protection other pins
- Pin-for-pin replacement and performance upgrade for competing products of similar nomenclature
- Single +5 V supply, +/-10% voltage tolerance, +4.5 to +5.5 V range
- Lower transceiver input current, less bus loading, than competing products
- Extremely low shutdown mode current (1 nA for ISL8487E and ISL81487L)
- Very low quiescent current - ISL8487E and ISL81487L (120 uA), ISL81487E (300 uA)
- Half-duplex bi-directional operation, differential signaling
- RS-485 and RS-422 compliant
- Fractional unit load 1/8 unit load devices for up to 256 nodes
- ISL8487E and ISL81487L slew-rate limited, less than 250 kbps data rate, low EMI
- ISL81487E 5 Mbps data rate
- -7 to +12 V common-mode input voltage range for reliable operation over long, noisy runs
- On-chip thermal shutdown
- Driver outputs short-circuit protected
- Three-state RX and TX output pins
- 8-lead PDIP and SOIC packages, -40 to +85 degree industrial temperature range
The ISL8487E, ISL81487L and ISL81487E are available now. Suggested resale pricing for 100- to 999-unit quantities is $1.20 each for either SOIC or PDIP packaging. SOIC packages are available on tape and reel. Visit this Intersil Web site for cross-reference and other information: http://www.intersil.com/interface/rs-485.asp About Intersil
Intersil Corporation is a leader in the design and manufacture of high performance analog semiconductors. The company’s products address three of the industry’s fastest growing markets - flat panel displays, optical storage (CD and DVD recordable) and power management. Intersil products include power management devices for battery management, hot-swap and hot-plug controllers, linear regulators, supervisory ICs, switching DC-DC regulators and power MOSFET drivers; optical storage laser diode drivers; DSL line drivers; video and high performance operational amplifiers; data converters; interface ICs; analog switches and multiplexers; crosspoint switches; voice-over-IP devices; and ICs for military, space and rad-hard applications. For more information about Intersil or to find out how to become a member of our winning team, visit the company’s web site and career page at: www.intersil.com.
This release may include "forward looking statements" that are subject to risks and uncertainties. For information identifying economic, political, climatic, currency, regulatory, technological, competitive and some other important factors that could cause actual results to differ materially from those anticipated in the forward looking statements, see Intersil’s Safe Harbor Forward Looking Statement disclaimer found at http://www.intersil.com/legal.asp, as well as Intersil’s SEC filings as updated from time to time, found at http://www.sec.gov. All other trademarks mentioned are the property of their respective owners.
