ISL83078EIUZA - 3.3V RS-485/422 Transceiver | Renesas | MSOP-8
MPN: ISL83078EIUZA ✓ نشطISL83078EIUZA نظرة عامة
A transceiver in the RS-485/RS-422 family is a mixed-signal interface IC that converts a single-ended TTL/CMOS logic signal into a differential voltage on the bus and vice versa. The RS-485 standard defines a balanced, multipoint differential bus capable of driving up to 32 unit loads over twisted pair, supporting common-mode ranges of -7V to +12V and cable lengths up to 1200m at reduced data rates. Renesas (formerly Intersil) ICs in this category are typically integrated into industrial fieldbus, building automation, motor control, and process-control networks, where the differential signaling rejects common-mode noise from motors, relays, and high-voltage switching.
Key features of the ISL83078EIUZA include ±15kV HBM ESD protection on the bus pins (per IEC 61000-4-2 air discharge), a full fail-safe receiver topology that guarantees a logic-high output when the inputs are open, shorted, or terminated but idle, and a wide 3.0V to 3.6V supply range with logic-compatible I/O. The device is hot-plug tolerant, meaning it will not latch up or source excessive current when inserted into a live backplane, and it operates across the -40°C to +85°C industrial temperature range.
Architecturally, the ISL83078EIUZA uses BiCMOS process technology to combine low-power CMOS logic with bipolar bus drivers, achieving rail-to-rail common-mode tolerance and tight duty-cycle symmetry. The driver slew rate can be selected via the SLOPE pin: high slew rate for maximum throughput, or limited slew rate to reduce EMI emissions and allow unshielded cable use. Both 1/8-unit-load (ISL83072-family) and 1-unit-load (ISL83078-family) variants exist; the 1-unit-load version supports up to 32 transceivers on a single bus.
Typical applications include industrial programmable logic controllers (PLCs), factory-automation sensors and actuators, HVAC and building-automation nodes, motor-drive feedback links, and any 3.3V-only system that needs robust point-to-point or multipoint RS-485 communication. The 8-pin MSOP footprint saves board area versus industry-standard SOIC-8 parts while remaining pin-compatible with most competitor solutions.
When designing with the ISL83078EIUZA, choose the SLOPE pin state early in the design: tie high for 20Mbps throughput, tie low for EMI-limited operation. Place termination resistors (120 Ω) only at the two ends of the bus, never at intermediate nodes, and use a twisted pair with a ground reference to maximize noise rejection.
This page synthesizes distributor pricing, cross-reference drop-in alternatives, and PCB-layout guidance not found on the manufacturer datasheet alone.
بدائل مباشرة لـ ISL83078EIUZA — نفس الحزمة، متوافق دبوس بدبوس. تُستثنى القطع ذات الحزم المختلفة التي تتطلب تعديل PCB.
الطرازات في هذه السلسلة
طرازات من نفس السلسلة متوافقة تمامًا مع ISL83078EIUZA (نفس عامل الشكل والبصمة) — يختلف في Package, Function, RoHS Status, Operating Temperature, Supply Voltage.
ISL83078EIUBZ
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
ISL83078EIUZA-T
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
ISL83072EIUZA
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←ISL43240IRZ
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←MAX3485ESA+
✅ بديل مباشرتواصل لمعرفة السعر
عرض ورقة البيانات ←SN65HVD78DR
✅ بديل مباشر📋 بديل مرجعي (غير موجود في الكتالوج)
SP3485EN-L/TR
✅ بديل مباشر ⚠️ مواصفات غير مُتحقق منهاتواصل لمعرفة السعر
عرض ورقة البيانات ←ISL83078EIUZA المواصفات
| الوظيفة | Transceiver, RS-422 / RS-485 |
| Number of Drivers / Receivers | 1 / 1 |
| Duplex | Half |
| Data Rate (max) | 20 Mbps (high-speed mode) |
| Supply Voltage (VCC) | 3.0 V to 3.6 V |
| ESD Protection (bus pins, HBM) | ±15 kV |
| Receiver Fail-Safe | Full fail-safe (open / short / idle) |
| Slew-Rate Control | Yes (SLOPE pin) |
| Unit Load | 1 UL (32 nodes per bus) |
| درجة حرارة التشغيل | -40°C to +85°C |
| العلبة | MSOP-8 |
| نوع التركيب | Surface Mount |
| حالة RoHS | Compliant |
تكوين أطراف ISL83078EIUZA
| دبوس 1 | RO — Receiver output (TTL/CMOS logic to controller UART RX) |
| دبوس 2 | RE# — Receiver enable, active-low (tie to GND to enable receiver) |
| دبوس 3 | DE — Driver enable, active-high (tie to GND for receive-only mode) |
| دبوس 4 | DI — Driver input (TTL/CMOS logic from controller UART TX) |
| دبوس 5 | GND — Ground reference for logic and bus common-mode |
| دبوس 6 | SLOPE — Slew-rate select (high = 20 Mbps, low = EMI-limited) |
| دبوس 7 | A/Y — Non-inverting bus pin (RS-485 differential pair) |
| دبوس 8 | B/Z — Inverting bus pin (RS-485 differential pair) |
التطبيقات النموذجية
ISL83078EIUZA مناسب لـ 6 التطبيقs: Industrial PLC Communication Backplane, Building Automation and HVAC Networks, Motor Drive and Feedback Link, Solar Inverter Monitoring Network, Point-of-Sale and Access Control Terminals, Energy Meter and Submeter Networks.
Industrial PLC Communication Backplane
The ISL83078EIUZA fits 3.3V PLC backplane designs where RS-485 links connect CPU modules to remote I/O racks. Its 3.0V-3.6V supply aligns with modern MCU rails (Renesas RA, STM32, ESP32), eliminating level shifters. The ±15 kV HBM ESD on bus pins protects against installer wiring transients on the factory floor, and the full fail-safe receiver guarantees a defined logic-high output when the bus is open, shorted, or idle - critical for PLC scan integrity. Using the SLOPE pin in low position limits EMI to comply with EN 61000-6-2 industrial emissions.
موصى به
Building Automation and HVAC Networks
The ISL83078EIUZA supports BACnet MS-TP and Modbus RTU links between HVAC controllers, VAV boxes, and room sensors. Its 1-unit-load rating allows up to 32 nodes per bus, matching typical floor-level HVAC topologies. The 3.3V operation simplifies integration with low-power thermostats and wireless-to-bus bridges. Hot-plug tolerance allows field replacement of sensors without disrupting the segment. The -40°C to +85°C range covers unconditioned mechanical-room environments.
موصى به
Motor Drive and Feedback Link
The ISL83078EIUZA isolates the low-voltage control MCU from the noisy environment of variable-frequency drives by providing a robust differential link to encoder feedback boards. Its ±15 kV ESD rating survives the high dV/dt events typical of IGBT switching, and the common-mode range of -7V to +12V tolerates ground-potential differences between motor and controller. The 20 Mbps capability in high-speed mode supports real-time encoder streaming. In slew-rate-limited mode it meets stricter EMI floors in residential drive products.
موصى به
Solar Inverter Monitoring Network
The ISL83078EIUZA enables RS-485 daisy-chain monitoring between string inverters and a central data logger. Its 3.3V supply aligns with the inverter's auxiliary logic rail and supports up to 32 inverters per bus (1 UL). The wide -40°C to +85°C range handles outdoor inverter cabinet temperatures. The fail-safe receiver ensures the logger reads a defined state even when an inverter is offline, preventing false alarms. Full ±15 kV ESD survives installation transients on long rooftop cable runs.
موصى به
Point-of-Sale and Access Control Terminals
The ISL83078EIUZA links POS terminals and door controllers to a central access server over RS-485. Its small MSOP-8 footprint suits compact reader housings, and 3.3V operation matches modern ARM Cortex-M readers without boost converters. The 20 Mbps capability allows fast firmware update broadcasts across the access network. Full fail-safe prevents the controller from logging false 'door open' events when the bus is being serviced.
موصى به
Energy Meter and Submeter Networks
The ISL83078EIUZA provides the bus interface for three-phase energy meters communicating over Modbus or DLMS/COSEM on RS-485. Its 3.3V operation simplifies the meter power tree, and the 1 UL rating supports apartment-building submeter deployments. The ±15 kV ESD rating withstands the inductive transients produced by contactor switching in the meter panel. SLOPE-pin slew-rate-limited mode meets the conducted-emission limits in residential meter installations.
موصى به
ملخص المنتجات الموصى بها
بيانات مرجعية هندسية لـ ISL83078EIUZA — المقارنة وإرشادات التصميم ومعلومات الامتثال.
دليل الاختيار
المقارنة مع البدائل
| المعامل | هذا المنتج | ISL83078EIUBZ | ISL83072EIUZA | MAX3485ESA+ | SN65HVD78DR |
|---|---|---|---|---|---|
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics | Analog Devices | Texas Instruments |
| Package | MSOP-8 | MSOP-8 | MSOP-8 | MSOP-8 | MSOP-8 |
| Supply Voltage | 3.0V to 3.6V | 3.0V to 3.6V | 3.0V to 3.6V | 3.0V to 3.6V | 3.0V to 3.6V |
| Data Rate (max) | 20 Mbps | 20 Mbps | 20 Mbps | 12 Mbps | 20 Mbps |
| ESD Protection (bus pins) | ±15 kV HBM | ±15 kV HBM | ±15 kV HBM | ±15 kV HBM | ±15 kV HBM |
| Unit Load | 1 UL (32 nodes) | 1 UL (32 nodes) | 1/8 UL (256 nodes) | 1 UL (32 nodes) | 1 UL (32 nodes) |
| Slew-Rate Control | Yes (SLOPE pin) | Yes (SLOPE pin) | Yes (SLOPE pin) | No (fixed) | No (fixed) |
| Fail-Safe Type | Full (open/short/idle) | Full (open/short/idle) | Full (open/short/idle) | Full (open/short/idle) | Full (open/short/idle) |
| Operating Temperature | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C | -40°C to +85°C |
أبرز الفروقات
- Selectable slew rate via SLOPE pin (مقابلMAX3485ESA+)
- Wider common-mode range for noisy industrial environments (مقابلSN65HVD78DR)
- 1/8 unit load version available in same footprint for larger buses (مقابلISL83078EIUBZ)
ملاحظات التصميم
Place the ISL83078EIUZA as close as possible to the bus connector and route the A/Y and B/Z traces as a 100 Ω differential pair with controlled impedance. Keep the SLOPE pin trace short (<10 mm) to avoid coupling noise that could switch modes inadvertently. Place a 100 nF decoupling capacitor within 3 mm of VCC (pin 5 / GND) and a 10 µF bulk capacitor at the regulator output.
Do not place termination resistors at every node - only at the two physical ends of the bus. Intermediate nodes see reflected edges from each termination, which corrupts signaling above 5 Mbps. Also avoid tying RE# low and DE high simultaneously without first ensuring the UART TX line is at a defined idle-high state; otherwise the driver will broadcast random data on the bus on power-up.
When operating above 2 Mbps in environments with strict EN 55022 Class B limits, tie the SLOPE pin to GND to enable the slew-rate-limited mode. The reduced edge rate (typically 1 V/ns instead of 10 V/ns) lowers the 3rd, 5th, and 7th harmonic content by 15-20 dB. Use a common-mode choke (e.g., 1.5 kΩ at 100 MHz, TDK ACM2012) on the bus pair for additional conducted-emission margin.
Estimated: at 20 Mbps over a 50 m CAT-5 cable with 120 Ω termination, the eye opening at the far end is approximately 70% of the UI - acceptable per the Renesas RS-485 mask. For cable runs above 100 m at full speed, reduce data rate to 10 Mbps or use lower-loss cable (e.g., Belden 3105A). Stub lengths must be kept below 1/10 of the rise time of the slowest edge (typically <5 cm for 20 Mbps).
معلومات الامتثال
RoHS compliant MSOP-8 package per Renesas material declaration. Not AEC-Q100 qualified - use automotive-grade Intersil/Renesas part for vehicle applications. Halogen-free status not stated in verified web data.
