SN65HVD70DGSR - 3.3V Full-Duplex RS-485 400kbps Transceiver, 10-VSSOP | Texas Instruments
MPN: SN65HVD70DGSR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.75 | $2.75 |
| 10 | $2.45 | $24.50 |
| 100 | $2.05 | $205.00 |
| 500 | $1.78 | $890.00 |
| 1,000 | $1.55 | $1,550.00 |
SN65HVD70DGSR Overview
A transceiver of this class is the physical-layer interface between a UART/MCU and a differential twisted-pair cable in industrial multipoint networks. The SN65HVD70 extends TI's RS-485 portfolio as a low-power, robust 3.3 V member of the SN65HVD7x family, suitable for half- and full-duplex links across factory floors, building automation, and motor-drive backplanes. As a line transceiver it sits hierarchically below the protocol layer (Modbus, PROFIBUS, DMX512) and above the cable plant, converting CMOS/TTL logic levels into the differential A/B signaling defined by TIA/EIA-485-A and TIA/EIA-422-B.
Key features include ±30 kV HBM ESD on the bus pins, a wide 3.0 V to 3.6 V supply range, a 1.8 V to 5 V logic interface (no level shifter needed in 1.8 V systems), open-circuit, short-circuit, and bus-idle fail-safe receiver inputs, and a thermal-shutdown protected driver. The 10-pin VSSOP package with thermal pad keeps the footprint compact while supporting industrial -40 °C to +125 °C operation.
The device uses a precision differential architecture with large receiver hysteresis (typically 50 mV) to reject common-mode noise on long cable runs. The wide common-mode range of -7 V to +12 V tolerates ground potential differences between nodes, and the 1/8 unit-load option permits up to 256 nodes on a single bus. Slew-rate limiting reduces EMI reflections on unterminated stubs.
Typical applications include industrial multi-drop RS-485 networks, building-automation backbones, motor-control command links, point-of-sale peripherals, and full-duplex RS-422 point-to-point data links. The device is well matched to long cable runs with proper 120 Ω termination at both ends.
When designing with this part, place 100 nF decoupling capacitors within 2 mm of VCC and use a 120 Ω termination resistor at each end of the bus. Do not leave unused driver outputs floating - tie them to GND through a resistor. Maintain a 1/8 unit-load budget when scaling beyond 32 nodes.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, including cross-vendor equivalents and full intent coverage in the FAQ for engineers planning second-source qualification.
Drop-in alternatives for SN65HVD70DGSR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with SN65HVD70DGSR (same form factor and footprint) — differing in Package, Product Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SN65HVD70DGS
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD70DGST
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD71DGSR
✅ Drop-In📋 Reference alternative (not in catalog)
MAX3485ESA+
✅ Drop-In✓ In Stock
$1.45 / Unit
View Datasheet →ISL3179EIBZ
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD70DGSR Specifications
| Product Type | RS-485 / RS-422 Transceiver |
| Protocol | RS-422, RS-485 |
| Number of Drivers/Receivers | 1/1 |
| Duplex | Full |
| Supply Voltage (VCC) | 3.0 V to 3.6 V |
| Data Rate | Up to 400 kbps |
| IEC ESD Protection (Contact) | ±12 kV (IEC 61000-4-2) |
| HBM ESD Protection (Bus pins) | ±30 kV (HBM) |
| Receiver Hysteresis | 50 mV (typical) |
| Common-Mode Range | -7 V to +12 V |
| Unit Load | 1/8 unit load (up to 256 nodes) |
| Driver Enable | Active-high |
| Receiver Enable | Active-low |
| Standby Current | < 5 µA (both disabled) |
| Operating Temperature | -40 °C to +125 °C |
| Package | 10-pin VSSOP (DGS) with PowerPAD |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
SN65HVD70DGSR Pin Configuration
| Pin 1 | RE — Receiver enable, active low. Tie low to enable receiver; tie high or open to put receiver in high-Z. |
| Pin 2 | RO — Receiver logic output. HIGH when (A - B) > 50 mV; LOW when (A - B) < -50 mV; HIGH when inputs open. |
| Pin 3 | DE — Driver enable, active high. Tie high to enable driver outputs; tie low to put driver in high-Z. |
| Pin 4 | DI — Driver logic input. Logic HIGH drives Y high and Z low; logic LOW drives Y low and Z high. |
| Pin 5 | GND — Ground reference for logic and bus. |
| Pin 6 | Y — Non-inverting driver output (bus side). |
| Pin 7 | Z — Inverting driver output (bus side). |
| Pin 8 | B — Inverting receiver input (bus side). |
| Pin 9 | A — Non-inverting receiver input (bus side). |
| Pin 10 | VCC — 3.3 V supply input. Decouple with 100 nF X7R within 2 mm. |
Typical Applications
SN65HVD70DGSR is suitable for 6 applications: Industrial Multi-Drop RS-485 Networks, Building-Automation Backbones, Motor Control Command Links, Point-of-Sale Peripherals, Full-Duplex RS-422 Point-to-Point Links, Security and Surveillance Camera Networks.
Industrial Multi-Drop RS-485 Networks
The SN65HVD70DGSR is engineered for industrial multi-drop RS-485 networks where a single MCU talks to up to 256 nodes over long twisted-pair cable runs. Its 1/8 unit-load receiver draws only 0.125 mA from the bus, allowing a full 256-node topology without exceeding the RS-485 common-mode loading budget. The ±12 kV IEC 61000-4-2 contact ESD rating protects the bus pins during cable hot-plug events in factory-floor enclosures, while the -7 V to +12 V common-mode range tolerates ground-potential differences between PLC cabinets powered from different phases. Pair the device with a 120 Ω termination at each bus end and a failsafe-bias resistor network. Typical protocols include Modbus RTU, PROFIBUS-DP at <= 400 kbps, and BACnet MS/TP.
Recommended
Building-Automation Backbones
In BACnet MS/TP, KNX, and LonWorks building-automation backbones, the SN65HVD70DGSR provides the 3.3 V physical layer for HVAC controllers, lighting panels, and access-control readers. The 1/8 unit-load budget accommodates daisy-chained device counts exceeding 100 nodes per segment, common in large commercial buildings. Its 400 kbps ceiling comfortably exceeds BACnet MS/TP's 76.8 kbps and 115.2 kbps tiers, while the wide 3.0 V to 3.6 V supply range tolerates voltage droops on long 24 V AC-derived rails. The VSSOP-10 footprint integrates cleanly onto small controller PCBs alongside a low-cost Cortex-M0 host MCU. Use a TVS diode such as SMAJ24CA on the bus for additional surge protection in outdoor or lightning-exposed runs.
Recommended
Motor Control Command Links
Variable-frequency drives and servo amplifiers use full-duplex RS-485 to receive position commands and broadcast telemetry back to a motion controller. The SN65HVD70DGSR's full-duplex architecture allows simultaneous torque/velocity command input and encoder feedback output on a single cable pair, simplifying cable harnesses in multi-axis machines. The ±12 kV IEC ESD rating protects against the large inductive-kickback transients typical of motor coils, and the -40 °C to +125 °C industrial temperature range suits sealed drive enclosures. For drives requiring > 400 kbps for high-resolution feedback, consider the SN65HVD75DGSR (20 Mbps, same footprint). Always include a 100 nF X7R decoupling capacitor within 2 mm of the VCC pin.
Recommended
Point-of-Sale Peripherals
Point-of-sale terminals and barcode-scanner hubs use full-duplex RS-485 to communicate with checkout-lane peripherals, scales, and receipt printers over 10 to 100 meter cable runs. The SN65HVD70DGSR's 3.3 V supply matches modern POS SoCs without requiring a level shifter, and the 1/8 unit load allows several peripherals on a single bus segment. The ±30 kV HBM ESD rating is critical for retail environments where cables are repeatedly plugged and unplugged by staff. The wide -7 V to +12 V common-mode range tolerates ground loops between checkout-counter electronics and back-office servers. The compact VSSOP-10 footprint suits space-constrained I/O boards behind displays.
Recommended
Full-Duplex RS-422 Point-to-Point Links
When a single RS-422 cable pair is run between two endpoints - for example, between an industrial sensor head and a remote display - the SN65HVD70DGSR's full-duplex architecture enables simultaneous upstream telemetry and downstream configuration commands. RS-422 supports higher data rates and longer cable runs than RS-232; the SN65HVD70 is rated for 400 kbps over up to 1200 meters of twisted pair, well within most industrial point-to-point requirements. The 1/8 unit-load receiver (here drawn explicitly) is not a factor in a two-node RS-422 link, but the low bus loading extends common-mode margin. Use a 100 Ω termination at each end for 22 AWG twisted pair.
Recommended
Security and Surveillance Camera Networks
PTZ surveillance cameras use full-duplex RS-485 to receive pan/tilt/zoom instructions from a control keyboard while streaming telemetry (azimuth, focus position, temperature) back to the operator. The SN65HVD70DGSR's ±12 kV IEC 61000-4-2 ESD rating protects the bus pins against static discharge during outdoor installation, and its -40 °C to +125 °C operating range handles unconditioned equipment closets. The 1/8 unit-load budget allows a single control bus to address > 32 cameras on a typical multi-story commercial site. The wide -7 V to +12 V common-mode range tolerates ground-potential differences between camera poles powered from different distribution transformers. Use shielded twisted pair (STP) and a single-point ground at the control room to minimize EMI from camera switching power supplies.
Recommended
Recommended Products Summary
Engineering reference data for SN65HVD70DGSR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN65HVD70DGS | SN65HVD70DGST | SN65HVD71DGSR | MAX3485ESA+ | ISL3179EIBZ |
|---|---|---|---|---|---|---|
| Package | 10-VSSOP (DGS) PowerPAD | 10-VSSOP (DGS) - same | 10-VSSOP (DGS) - same | 10-VSSOP (DGS) - same | 10-VSSOP - same | 10-VSSOP - same |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Maxim Integrated | Renesas Electronics |
| Supply Voltage | 3.0 V to 3.6 V | 3.0 V to 3.6 V | 3.0 V to 3.6 V | 3.0 V to 3.6 V | 3.0 V to 3.6 V | 3.0 V to 3.6 V |
| Max Data Rate | 400 kbps | 400 kbps | 400 kbps | 400 kbps | 32 Mbps | 25 Mbps |
| IEC ESD (Contact) | ±12 kV | ±12 kV | ±12 kV | ±12 kV | ±8 kV | ±15 kV |
| Unit Load | 1/8 UL | 1/8 UL | 1/8 UL | 1/8 UL | 1 UL | 1 UL |
| Driver / Receiver Enable | DE active-high, RE active-low | DE active-high, RE active-low | DE active-high, RE active-low | None (always enabled) | DE active-high, RE active-low | DE active-high, RE active-low |
| Common-Mode Range | -7 V to +12 V | -7 V to +12 V | -7 V to +12 V | -7 V to +12 V | -7 V to +12 V | -7 V to +12 V |
Key Differentiators
- 1/8 unit-load supports up to 256 nodes (vs MAX3485ESA+)
- ±12 kV IEC 61000-4-2 contact ESD rating (vs MAX3485ESA+)
- Slew-rate-limited driver for EMI compliance (vs ISL3179EIBZ)
Design Notes
Place a 100 nF X7R (or better) decoupling capacitor within 2 mm of the VCC pin, with a short, wide trace to GND. The exposed thermal pad of the VSSOP-10 PowerPAD package must be soldered to a grounded copper pour (at least 25 mm² of 1 oz copper) to meet the ±12 kV IEC ESD and thermal performance specified in the TI datasheet. Keep bus traces matched in length and impedance (120 Ω differential) and avoid routing them parallel to switching power converter traces.
Do not leave unused driver outputs (Y, Z) floating when DE is disabled - the floating state may inject common-mode noise into the receiver through the bus. Tie unused outputs to GND through a 1 kΩ resistor. Likewise, never float DE or RE; tie DE to GND through a 100 kΩ pull-down and RE to VCC through a 100 kΩ pull-up if unused, to keep the device in a defined standby state with < 5 µA current.
Use a 120 Ω termination resistor at each end of the bus, matched to the cable differential impedance (typically 120 Ω for AWG 24 twisted pair). For multi-drop RS-485 with stubs, keep stub lengths shorter than 1/10 of the driver's rise time × propagation velocity to avoid reflections. Place the failsafe-bias resistor network (typically 680 Ω pull-up to 5 V on A and 680 Ω pull-down to GND on B with a 120 Ω parallel termination) only at one end of the bus to bias the idle state.
For cable runs longer than 10 m, use shielded twisted pair (STP) with the shield grounded at one end only to avoid ground loops. The SN65HVD70DGSR's ±12 kV IEC ESD protects against static discharge but does not protect against sustained over-voltage from cable cross-wiring to a 24 VAC bus - add an external TVS such as SMAJ24CA across the bus pins for surge protection in outdoor or industrial installations.
Compliance Information
RoHS and REACH compliant per TI product page. Not AEC-Q100 qualified - choose SN65HVD70-Q1 if automotive qualification is required. Industrial -40°C to +125°C operating range.
