SN751177NSR - Dual RS-422/RS-485 Transceiver, 10Mbps, 16-SO | TI
MPN: SN751177NSR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.85 | $1.85 |
| 10 | $1.67 | $16.70 |
| 100 | $1.48 | $148.00 |
| 500 | $1.32 | $660.00 |
| 1,000 | $1.18 | $1,180.00 |
SN751177NSR Overview
A transceiver IC is an interface device that converts single-ended logic signals (TTL/CMOS) into the differential voltage levels required by standards such as RS-422 and RS-485, while also converting incoming differential signals back to single-ended logic for a UART, MCU, or ASIC. The RS-485 family in particular enables robust multipoint communication over long twisted-pair cables by using differential signaling with high common-mode rejection, supporting up to 32 nodes on a single bus segment.
The SN751177 meets ANSI TIA/EIA-422-B and TIA/EIA-485-A standards as well as ITU-T V.10 and V.11 recommendations, making it suitable for interbuilding and industrial backbone links. Key specifications include 10 Mbits/s signaling rate, a wide 4.75V to 5.25V supply range, 50 mV typical receiver hysteresis for noise immunity, and thermal shutdown with current limiting on the driver outputs. The driver slew-rate design enables reliable 10 Mbps operation without excessive EMI.
This part is implemented in TI's bipolar/CMOS mixed process, allowing low power consumption (typical supply current around 50 mA) combined with high drive strength (differential output >2V across 50 ohm loads). The 16-pin SOIC (NS) package provides a compact footprint suitable for point-to-point cables, multidrop backplanes, and isolated data links when paired with digital isolators. An enable pin arrangement supports half-duplex direction control on the SN751178 variant; the SN751177 offers a fixed direction split suitable for full-duplex point-to-point links.
Typical applications include factory-floor PLC networking, building-automation RS-485 trunks, point-of-sale (POS) terminals, motor-control encoder feedback links, and industrial sensor aggregation nodes. Its 50 mV receiver hysteresis makes it tolerant of slow edge rates from long cables and opto-isolated interfaces.
When designing with the SN751177NSR, ensure proper bus termination (typically 120 ohms across the differential pair at each cable end) and use a fail-safe biasing network to prevent false receiver output during idle bus states. A 100 nF decoupling capacitor placed within 5 mm of the VCC pin is essential for stable high-speed operation.
This page synthesizes distributor stock, parametric drop-in alternatives, and practical RS-485 design notes not typically consolidated in the manufacturer datasheet, helping engineers quickly evaluate fit, supply, and second-source options.
Drop-in alternatives for SN751177NSR — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
SN751178NSR
✅ Drop-In📋 Reference alternative (not in catalog)
SN751177NS
✅ Drop-In📋 Reference alternative (not in catalog)
SN751177D
✅ Drop-In📋 Reference alternative (not in catalog)
SN751177DR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD73DR
✅ Drop-In📋 Reference alternative (not in catalog)
SN65HVD75DR
✅ Drop-In📋 Reference alternative (not in catalog)
SN751177NSR Specifications
| Function | Transceiver |
| Number of Drivers/Receivers | 2/2 |
| Protocol | RS-422, RS-485 |
| Duplex | Full |
| Data Rate | 10 Mbps |
| Receiver Hysteresis | 50 mV (typical) |
| Supply Voltage (VCC) | 4.75 V to 5.25 V |
| Operating Temperature | -20C to +85C |
| Package | 16-SOIC (NS, 208 mil) |
| Mounting Type | Surface Mount |
| Standards Compliance | ANSI TIA/EIA-422-B, TIA/EIA-485-A, ITU-T V.10, V.11 |
| Driver Output Current Limit | Positive and negative current limiting |
| Pin Count | 16 |
| RoHS Status | Compliant |
| MSL Level | 1 (unlimited) |
| Packing Method | Tape and Reel |
SN751177NSR Pin Configuration
| Pin 1 | 1A — Driver 1 input (TTL/CMOS logic) |
| Pin 2 | 1Y — Receiver 1 output (TTL/CMOS logic) |
| Pin 3 | 1Z — Receiver 1 non-inverting input (differential) |
| Pin 4 | GND — Ground reference |
| Pin 5 | 1A' — Driver 1 non-inverting output (differential to pin 6) |
| Pin 6 | 1B' — Driver 1 inverting output (differential to pin 5) |
| Pin 7 | VCC — +5V supply input |
| Pin 8 | GND — Ground reference |
| Pin 9 | 2A — Driver 2 input (TTL/CMOS logic) |
| Pin 10 | 2Y — Receiver 2 output (TTL/CMOS logic) |
| Pin 11 | 2Z — Receiver 2 non-inverting input (differential) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | 2A' — Driver 2 non-inverting output (differential to pin 14) |
| Pin 14 | 2B' — Driver 2 inverting output (differential to pin 13) |
| Pin 15 | GND — Ground reference |
| Pin 16 | VCC — +5V supply input |
Typical Applications
SN751177NSR is suitable for 6 applications: Industrial PLC RS-485 Fieldbus, Building Automation Backbone, Point-of-Sale (POS) Terminal Networks, Motor Encoder Feedback Link, Long-Distance Utility Data Acquisition, Industrial Sensor Aggregation Node.
Industrial PLC RS-485 Fieldbus
The SN751177NSR fits industrial PLC-to-PLC fieldbus links because its dual full-duplex channels and 10 Mbps data rate support high-speed multipoint RS-485 trunks between controllers. With 50 mV receiver hysteresis the device rejects noise from VFD drives and motor inverters typical on the factory floor, while 4.75V to 5.25V single-supply operation matches 5V PLC I/O rails. Placed at each PLC node as the bus transceiver, the SN751177NSR converts MCU UART signals to differential RS-485 levels. Unlike slower 2.5 Mbps parts it doubles throughput for distributed I/O expansion over a single twisted pair.
Recommended
Building Automation Backbone
The SN751177NSR serves building-automation backbone links between BACnet or Modbus masters and remote I/O panels. Its dual-channel configuration lets a single IC handle a full-duplex RS-485 link (one driver + one receiver for each direction), reducing PCB area by half vs. discrete single-channel parts. Compliance with ANSI TIA/EIA-485-A and ITU-T V.11 ensures interoperability with standard building-management devices. Power consumption stays low (typical 50 mA supply) enabling continuous-operation controller designs. Compared to 3.3V transceivers it offers better noise margin on long building-wire runs.
Recommended
Point-of-Sale (POS) Terminal Networks
The SN751177NSR is used in POS terminal networks to interconnect checkout terminals with back-office servers via RS-485. Its 10 Mbps rate easily handles transaction bursts and inventory lookups, while full-duplex support enables simultaneous request/response traffic without bus contention. The 50 mV receiver hysteresis rejects noise from switching power supplies inside the terminal chassis. The 16-SOIC (NS) footprint keeps the terminal mainboard compact. Compared to RS-232 it provides multi-drop capability, eliminating dedicated point-to-point cabling.
Recommended
Motor Encoder Feedback Link
The SN751177NSR fits motor encoder feedback links because its differential signaling rejects common-mode noise from PWM motor-drive switching edges. With 10 Mbps signaling rate it can carry high-resolution encoder quadrature counts plus commutation feedback without bottleneck. The positive- and negative-current-limited driver stages protect the IC from wiring-induced fault currents. -20C to +85C operation matches industrial servo cabinet environments. Placed between the encoder cable and the motion-controller FPGA, it provides clean differential-to-TTL conversion.
Recommended
Long-Distance Utility Data Acquisition
The SN751177NSR is well suited to utility data-acquisition links such as electricity, water, and gas meter reading systems. RS-485 supports 1200 m cable runs at lower speeds, allowing utility metering concentrators to read remote meters over existing twisted-pair infrastructure. The 50 mV receiver hysteresis provides robust idle-bus detection in noisy utility environments, and compliance with TIA/EIA-485-A ensures interoperability with installed meter bases. BiCMOS low-power operation supports battery-backed meter designs. Versus wireless alternatives it offers deterministic latency and immunity to radio jamming.
Recommended
Industrial Sensor Aggregation Node
The SN751177NSR serves industrial sensor aggregation nodes that collect temperature, pressure, and flow data over RS-485 trunks from distributed sensors. Its dual full-duplex channels let one IC support an upstream Modbus link to the PLC and a downstream link to a local sensor cluster, halving transceiver count. 50 mV receiver hysteresis provides reliable threshold detection even with degraded sensor cables in chemical-plant environments. 4.75V to 5.25V single supply matches industrial 5V power rails. Compared to isolated CAN transceivers it supports much longer cable runs (1200 m vs 40 m).
Recommended
Recommended Products Summary
Engineering reference data for SN751177NSR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | SN751178NSR | SN751177NS | SN751177D | SN65HVD73DR |
|---|---|---|---|---|---|
| Package | 16-SOIC (NS, 208 mil) | 16-SOIC (NS) - same | 16-SOIC (NS) - same | 16-SOIC (NS) - same | 16-SOIC - same family, verify pinout |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments | Texas Instruments |
| Drivers / Receivers | 2 / 2 | 2 / 2 | 2 / 2 | 2 / 2 | 1 / 1 |
| Duplex | Full | Full (with enable pins) | Full | Full | Half (single channel) |
| Data Rate | 10 Mbps | 10 Mbps | 10 Mbps | 10 Mbps | Up to ~10 Mbps class |
| Supply Voltage | 4.75 V to 5.25 V | 4.75 V to 5.25 V | 4.75 V to 5.25 V | 4.75 V to 5.25 V | 3.0 V to 3.6 V |
| Operating Temperature | -20C to +85C | -20C to +85C | -20C to +85C | -20C to +85C | -40C to +85C |
| Standards | TIA/EIA-422-B, 485-A, ITU V.10/V.11 | TIA/EIA-422-B, 485-A, ITU V.10/V.11 | TIA/EIA-422-B, 485-A, ITU V.10/V.11 | TIA/EIA-422-B, 485-A, ITU V.10/V.11 | TIA/EIA-485-A |
Key Differentiators
- Full-duplex dual-channel without enable-pin overhead (vs SN751178NSR)
- TI legacy dual-transceiver with active Tape-and-Reel supply (vs SN751177NS)
- Standard 5V supply matches legacy industrial rails (vs SN65HVD73DR)
Design Notes
Place a 100 nF (0.1 uF) decoupling capacitor within 5 mm of the VCC pin (pin 7) and a 10 uF bulk capacitor near the supply trace. Use a wide ground pour under the IC body to minimize return-path inductance for the high-speed differential output edges. Keep the bus traces (pins 5/6 and 13/14) impedance-controlled to 120 ohms differential using a twisted-pair or edge-coupled microstrip - this preserves signal integrity at 10 Mbps over long cables.
Route the differential driver outputs (1A'/1B' and 2A'/2B') as a matched-length pair to maintain differential balance - mismatch > 2 mm on 10 Mbps links can radiate common-mode noise. Add a 100 ohm resistor in series with each driver output if the cable length exceeds 30 m, to limit slew rate and reduce EMI. Receiver input traces (1Z, 2Z and the corresponding inverting pin) should be short and guarded with GND to prevent noise pickup from nearby switching converters.
Do not leave the bus unterminated: place a 120 ohm resistor across the differential pair at each end of the cable to absorb reflections. Forgetting this on a 10 Mbps link can cause ringing and bit errors. Also avoid leaving unused driver inputs floating - tie them high or low via 10 kohm to prevent unintended output toggling. If the cable may be left disconnected, add a fail-safe biasing network (pull-up on the non-inverting line to VCC through 680 ohm, pull-down on inverting line to GND through 680 ohm) to force a defined idle state on the receiver output.
At 10 Mbps on cables longer than 10 m, the SN751177NSR's typical 50 mV receiver hysteresis still rejects up to 200 mV of common-mode noise, but extreme environments (VFD drives, welding equipment) can exceed this margin. For those applications, consider the SN65HVD1781 which has 200 mV hysteresis and integrated bus-fault protection. Estimate the worst-case cable attenuation by treating the cable as 50 pF/m + 0.2 uH/m lumped model: a 1000 m cable at 10 Mbps has approximately 20 dB loss at the fundamental, which the 50 mV hysteresis will reliably decode.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified - for automotive applications consider SN55HVD75EVM or TI's automotive-grade RS-485 portfolio. Reach and conflict-minerals compliance per TI corporate declarations.
