SN65HVD35D - 3.3V Full-Duplex RS-485 Transceiver | Texas Instruments
MPN: SN65HVD35D ✗ End of LifeSN65HVD35D Overview
An RS-485 transceiver is the physical-layer building block for balanced, differential, two-wire multidrop data buses. The SN65HVD3x family combines a 3-state differential line driver, a differential line receiver, and the enable logic needed to put each side into a high-impedance state. In the SN65HVD35D, the driver enable is active high and the receiver enable is active low, so a host microcontroller can drive the bus and listen independently, which is essential for full-duplex designs such as point-to-point links and multi-drop industrial field buses.
Key features include bus-pin ESD protection exceeding 15 kV HBM, a low-current standby mode drawing only 1 uA, glitch-free receiver outputs that prevent false start bits during noise transients, and a receiver input hysteresis of 50 mV that rejects differential noise at the input comparator. The device also supports RS-422 signalling and cable runs of up to 1500 meters in the appropriate system configuration.
Internally, the SN65HVD3x family uses a differential receiver with internal hysteresis and an output driver stage with selectable edge-rate control, giving designers a way to reduce EMI on slow networks without giving up throughput on fast links. Separate input and output pins for both the driver and receiver make bus-direction control straightforward at the digital side.
Typical applications include industrial RS-485 fieldbus transceivers, building and HVAC automation controllers, industrial sensor and actuator nodes, instrumentation over long twisted-pair runs, and point-to-point links between a microcontroller and a peripheral board using a separate transmit and receive pair.
When laying out the board, keep the A and Y (and B and Z) differential pair routed as a tightly coupled pair over a continuous ground reference, and place the bus-side protection and termination network close to the connector. Because the transceiver is a 3.3 V device, its bus-side interface does not provide isolation or level translation for 5 V legacy nodes, so a galvanic barrier should be added when the far end of the cable is at a different ground potential.
This page consolidates the key electrical ratings, drop-in replacement options within the SN65HVD3x family, and practical layout guidance for engineers who need to bring a full-duplex RS-485 node onto a 3.3 V board with a 14-pin SOIC footprint.
Drop-in alternatives for SN65HVD35D — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
SN65HVD35DR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD35DG4
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD35DRG4
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD34DR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD33DR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD35D Specifications
| Device Type | RS-422 / RS-485 differential transceiver (1 transmitter, 1 receiver) |
| Supply Voltage Range | 3 V to 3.6 V |
| Nominal Supply Voltage | 3.3 V |
| Duplex Type | Full duplex (separate driver and receiver pins) |
| Number of Drivers / Receivers | 1 / 1 |
| Maximum Data Rate | 1 Mbps |
| Driver Transition Rate Options | 1 Mbps, 5 Mbps and 25 Mbps signaling rates |
| Receiver Hysteresis | 50 mV |
| Receiver Unit Load | 1/8 UL (up to 256 nodes on the bus) |
| ESD Protection (HBM, bus pins) | Exceeds 15 kV HBM |
| Standby / Shutdown Current | 1 uA low-current standby mode |
| Glitch-Free Receiver Output | Yes |
| Enable Configuration | Active-high driver enable (DE), active-low receiver enable (RE) |
| Operating Temperature Range | -40 C to +85 C |
| Maximum Cable Length | Up to 1500 m |
| Package | SOIC-14, MS-012AA, 14 pins |
| Mounting Type | Surface mount |
| Supported Standards / Technology | RS-422 and RS-485 |
| Product Status | Listed as Obsolete by distributor product-status records |
SN65HVD35D soic-14, ms-012aa, 14 pins Pin Configuration Guide
Pin configuration for SN65HVD35D (soic-14, ms-012aa, 14 pins package). Pin numbering, functions, and connection diagrams are defined in the manufacturer datasheet. Refer to it for the exact footprint and soldering guidelines.
No detailed pinout data available for SN65HVD35D.
Refer to the datasheet for full pin configuration.
Typical Applications
SN65HVD35D is suitable for 6 applications: Industrial RS-485 Fieldbus Node, Building and HVAC Automation Controller, Point-to-Point Long-Distance Link, Industrial Sensor and Actuator Node, Instrumentation and Test Equipment Front Panel, Motor Drive and Power Electronics Communication.
Industrial RS-485 Fieldbus Node
The SN65HVD35D suits industrial RS-485 fieldbus nodes because it combines a 3.3 V supply with a 1/8 unit-load receiver, so up to 256 nodes can share one twisted-pair bus without loading the network. The active-high driver enable and active-low receiver enable let the host microcontroller take the bus only when it transmits, keeping the line released to high impedance between frames. With bus-pin ESD protection exceeding 15 kV HBM, the transceiver tolerates electrostatic discharge events that occur when field cabling is plugged and unplugged at the enclosure. A 50 mV receiver hysteresis rejects common-mode noise from adjacent machinery, which is critical when the bus runs alongside motor and relay wiring in the same cable tray.
Recommended
Building and HVAC Automation Controller
Building HVAC controllers talk to distributed air-handling units, dampers and sensors over RS-485, typically from a 3.3 V system rail in a low-cost embedded controller. The SN65HVD35D provides a full-duplex channel, so the controller can transmit setpoints and simultaneously receive sensor telemetry without having to arbitrate a half-duplex bus, which simplifies the firmware timing budget. Its 1 Mbps capability is far above the few kilobits per second that HVAC polling typically requires, and the selectable 1 Mbps, 5 Mbps and 25 Mbps driver transition rates let you slow the edges to suppress EMI in installations where the controller sits next to variable-speed motors and dimmable lighting.
Recommended
Point-to-Point Long-Distance Link
For a point-to-point link between two boards separated by up to 1500 meters of twisted pair, the SN65HVD35D is a straightforward choice because full-duplex operation uses separate differential pairs for transmit and receive, eliminating turnaround delays. The 3 V to 3.6 V supply range matches modern 3.3 V system rails directly, avoiding the level-shift circuitry needed for 5 V transceivers. Driver transition-rate selection matters over long cables: using the slower 1 Mbps option lowers radiated emissions and reduces reflections on unterminated runs. Because this device provides no isolation, add a digital isolator when the remote end of the cable is at a different ground potential, otherwise ground currents can corrupt the differential signal or damage the transceiver.
Recommended
Industrial Sensor and Actuator Node
Distributed sensor and actuator nodes in a machine often need a robust, low-power 3.3 V bus interface that can be powered down between measurements. The SN65HVD35D includes a low-current standby mode drawing only 1 uA, which suits battery-assisted or energy-harvesting field nodes that spend most of their time asleep and wake only to transmit a reading. The glitch-free receiver output prevents a corrupted character from appearing at the logic pins during noise transients, which avoids false data being logged in a condition-monitoring system. Because the receiver presents only 1/8 unit load, a large number of remote sensor nodes can be daisy-chained along a single run while remaining inside the bus loading budget.
Recommended
Instrumentation and Test Equipment Front Panel
Laboratory and industrial instrumentation front panels often need to drive a full-duplex RS-485 command channel from a single 3.3 V controller while remaining tolerant of noisy bench environments. The SN65HVD35D separates driver and receiver control, so the instrument can keep its receiver active while the driver is idle, avoiding the dead time that half-duplex implementations introduce when the bus direction flips. The 50 mV receiver hysteresis and glitch-free output help preserve integrity of measurement commands and responses that are logged and audited. Because the device has no isolation and its bus pins are exposed to user cabling, pair it with a surge and TVS protection network close to the connector.
Recommended
Motor Drive and Power Electronics Communication
Servo drives, frequency inverters and DC drives commonly expose an RS-485 port for parameter download and status polling, and these platforms often run their control logic from a 3.3 V rail. The SN65HVD35D is a practical fit for that port because it can hold the bus released while the drive is busy and only assert the driver enable during a transmission, which prevents the drive electronics from fighting other nodes. The selectable slower driver transition rate is valuable in an enclosure containing switching stages, since reduced edge speed lowers common-mode and radiated emissions coupling into the analog measurement paths. A galvanic isolator in front of the transceiver is recommended when the drive bus crosses an isolation barrier inside the cabinet.
Recommended
Recommended Products Summary
Engineering reference data for SN65HVD35D — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN65HVD35DR | SN65HVD35DG4 | SN65HVD34DR | SN65HVD33DR |
|---|---|---|---|---|---|
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Package | SOIC-14 (MS-012AA) | SOIC-14 (MS-012AA) - same | SOIC-14 (MS-012AA) - same | SOIC-14 (MS-012AA) - same | SOIC-14 (MS-012AA) - same |
| Supply Voltage Range | 3 V to 3.6 V | 3 V to 3.6 V | 3 V to 3.6 V | 3 V to 3.6 V | 3 V to 3.6 V |
| Driver / Receiver Count | 1 / 1 | 1 / 1 | 1 / 1 | 1 / 1 | 1 / 1 |
| Duplex Mode | Full duplex | Full duplex | Full duplex | Full duplex | Full duplex |
| Enable Configuration | Active-high DE, active-low RE | Active-high DE, active-low RE | Active-high DE, active-low RE | Active-high DE, active-low RE | Active-high DE, active-low RE |
Key Differentiators
- Independent active-high driver enable and active-low receiver enable (vs SN65HVD30 / SN65HVD31 / SN65HVD32 (fully enabled, no external enable pins))
- Selectable driver output transition times (vs SN65HVD33DR)
- 1/8 unit-load receiver with 50 mV hysteresis (vs SN65HVD34DR)
- Common 14-pin SOIC (MS-012AA) footprint across the whole substitution set (vs SN65HVD34DR)
Design Notes
Route the driver outputs and receiver inputs as tightly coupled differential pairs (A/B and Y/Z) over a continuous ground plane, and keep the pair length matched within a few millimetres to avoid skew that shows up as differential noise at the comparator. Place the bus-side protection components and the termination and biasing network right at the connector rather than at the transceiver, so the high-current switching transients are clamped before they propagate into the device. Keep the ground reference continuous under the pair to reject common-mode noise from adjacent switching stages.
The receiver enable on this device is active low, so a floating or pulled-high RE pin disables the receiver and produces no data, a symptom often misdiagnosed as a wiring fault. Add a defined pull resistor so the bus state is deterministic at reset. Also note that the enable pins are logic-side signals with no internal fail-safe bias, and that the device provides no isolation and no 5 V bus-level compatibility; add a digital isolator or level translator if the far end of the cable is at a different ground potential or runs legacy 5 V nodes.
Use the slower driver transition-rate option when the bus is long or runs next to noisy equipment. Slowing the output edges reduces radiated emissions and ringing on unterminated stubs, which matters when the transceiver sits in the same enclosure as variable-speed drives or switching relays. If the link runs at the full 1 Mbps rate, keep the cable run short, terminate both ends of the differential pair in the standard way, and avoid stub branches, because each stub acts as a discontinuity that reflects energy back into the driver output stage.
Estimated: the transceiver is a 3.3 V, low-power device, but the real supply budget on a bus node is usually dominated by external protection and isolation components. Decouple the 3.3 V rail locally with a 100 nF ceramic capacitor placed close to the supply pin and back it up with a bulk capacitor of a few microfarads at the rail entry, so that bus switching transients do not dip the transceiver supply below its operating minimum. Verify that any 3.3 V rail shared with switching circuitry stays within tolerance across the full temperature range of -40 C to +85 C.
Compliance Information
The SN65HVD35D is a commercial-grade RS-485 transceiver rated from -40 C to +85 C and is not marketed as an AEC-Q100 qualified automotive part. RoHS, REACH, lead-free and halogen-free declarations for this specific ordering code should be confirmed with the manufacturer before use in a regulated end product.
