ISL3158AEMBZ-T7A

Overview

The ISL3158AEMBZ-T7A is a half-duplex RS-485/RS-422 transceiver in an 8-lead SOIC package. It operates on a single 5V supply (4.5V to 5.5V) with a maximum data rate of 10Mbps. The device features ±16.5kV IEC61000-4-2 ESD protection on A/Y and B/Z pins, a true 1/8 unit load allowing up to 256 devices per bus, and full fail-safe receiver inputs. Quiescent current is typically 600µA, dropping to 70nA in shutdown mode. Driver differential output voltage is min 2.4V at 54Ω, supporting extended common mode range from -7V to +12V.

Feature Summary

• High driver differential output voltage improves noise immunity and supports non-standard bus topologies like star configurations.
• Integrated hot plug circuitry maintains high-impedance states during power-up and power-down to prevent bus crashes.
• Advanced ESD structures protect RS-485 I/O pins against severe electrostatic discharge events without external components.

Applications

• Utility meters and automated meter reading systems
• High node count PROFIBUS and field bus networks
• Security camera networks
• Industrial process control networks

Procurement Notes

Verify the specific ordering suffix matches the required packaging format. The '-T7A' suffix indicates tape and reel configuration. Confirm the moisture sensitivity level and reflow profile requirements align with your assembly process. Ensure the temperature range of -55°C to +125C meets your operational environment specifications before finalizing procurement.

Selection Notes

Select this component for applications requiring high node density due to its 1/8 unit load characteristic. It is suitable for noisy environments benefiting from large differential output swings and robust ESD protection. Consider the shutdown current if power conservation is critical. Verify that the half-duplex pinout fits your board layout constraints compared to full-duplex alternatives.

Part Context

This part belongs to the ISL3158AE family of BiCMOS transceivers designed for RS-485 and RS-422 communication standards. It shares core electrical characteristics with other variants in the series but differs in packaging and shipping configuration. The device was originally manufactured by Intersil, which is now part of Renesas Electronics Corporation.

Replacement Considerations

Public datasheets list ISL3158E and ISL3158AE as possible substitutes. Verify compatibility regarding package dimensions, pinout assignments, and electrical specifications before substitution. Ensure the substitute part meets the same ESD protection levels and operating temperature ranges.

FAQ

How does the 1/8 unit load feature benefit network design?

It allows up to 256 transceivers on a single RS-485 bus without violating the standard's 32 unit load limit, eliminating the need for repeaters in large installations.

What triggers the shutdown mode in the ISL3158AEM?

Shutdown mode activates when both the receiver enable (RE) and driver enable (DE) inputs are disabled simultaneously for a duration exceeding 600ns.

Can this device operate with common mode voltages outside the supply rails?

Yes, the receiver inputs and driver outputs support a common mode voltage range of -7V to +12V, accommodating ground potential differences and induced cable voltages.