Analysis
RS-485/RS-422 single transmitter from Intersil
Intersil has introduced the ISL329xE series of 3.3V-powered RS-485/RS-422 single transmitters designed with excellent +/-16.5kV ESD protection and ultra-low supply current requirement. These devices come in very small TDFN and SOT23 packages with both package types available in the industrial and extended industrial (-40C to +125C) temperature ranges.
ThisThis family of transmitters has low quiescent supply current (Icc = 150 microamps max). That is 1/30th the value of the nearest competitor, making a significant improvement in power critical applications. Additionally, all the devices feature a Tx enable pin that places the IC in a low power shutdown mode (Icc = 1 microamps max) to further reduce power consumption whenever the transmitter is disabled.
The ISL3296E, ISL3297E and ISL3298E are all available in 8-lead TDFN packaging (2mm x 3mm) that is 26% smaller than SOT23 package options (3mm x 3mm), saving valuable board space. These versions feature on-board level translators on the enable and data input pins that simplify the design of mixed voltage systems. The logic supply pin (VL) can be connected to a lower voltage processor supply to level shift the input voltages to values compatible with the processor supply. This eliminates the need for external level translators.
The rugged performance of these devices is demonstrated by the high level of ESD protection on the transmitter outputs that are typically exposed to the outside world, as well as the 125C temperature operating range and enhanced thermal performance of the TDFN package option.
Coupled with the ISL328xE family of single RS-485/RS-422 receivers, a user can build a small footprint, highly reliable serial communication port.
The ISL3293E, ISL3294E and ISL3295E are available in SOT23 packaging, and the ISL3296E, ISL3297E and ISL3298E are available in TDFN packaging in.