MAX14931AASE+T - 4-Ch 1Mbps 2.75kVrms Digital Isolator | ADI
MPN: MAX14931AASE+T ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.16 | $6.16 |
| 10 | $5.55 | $55.50 |
| 100 | $4.94 | $494.00 |
| 500 | $4.45 | $2,225.00 |
| 1,000 | $3.98 | $3,980.00 |
MAX14931AASE+T Overview
A digital isolator is a semiconductor device that uses an internal isolation barrier - typically a capacitive, magnetic, or optical coupling structure - to transmit logic-level signals between two galvanically isolated voltage domains while blocking DC and low-frequency currents. Digital isolators replace optocouplers in modern designs and are classified within the broader signal-chain and interface-IC family. They are key building blocks for reinforced insulation, functional safety, and high-voltage system partitioning.
Key features of the MAX14931AASE+T include 2750 Vrms withstand voltage, 1 Mbps guaranteed data rate across -40 °C to +125 °C, 25 kV/µs typical common-mode transient immunity, low propagation delay of 42.9 ns, and 1.71 V minimum supply voltage. The wide-body SOIC-16 package provides the required creepage and clearance for reinforced isolation at 2.75 kVRMS, simplifying PCB layout for industrial bus isolation.
Internally, the MAX14931AASE+T uses Maxim's proprietary CMOS isolation technology with integrated dc-dc converter control on the secondary side for optional isolated power. Each of the four channels is unidirectional, three in one direction and one in the reverse direction, matching typical SPI / UART peripheral-interface signalling patterns without requiring external direction-control logic.
Typical applications include isolated SPI interfaces for industrial PLCs, isolated RS-485 transceivers in factory automation, isolated gate-drive signal conditioning for motor drives, and medical device patient-isolated data links. The wide operating temperature range supports both industrial and automotive-grade designs.
When designing with this device, follow the SOIC-16 wide-body creepage and clearance guidelines: maintain at least 8 mm of PCB spacing under the package body and avoid routing copper traces between pins to preserve the 2.75 kVRMS rating. Decouple both VDD pins with 0.1 µF low-ESR ceramic capacitors placed within 2 mm of the supply pins.
Drop-in alternatives for MAX14931AASE+T — 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 MAX14931AASE+T (same form factor and footprint) — differing in Number of Channels, Package, Channel Configuration, Common-Mode Transient Immunity (CMTI), Isolation Technology.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MAX14930AASE+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX14932AASE+T
✅ Drop-In📋 Reference alternative (not in catalog)
MAX14931FASE+T
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX14931AASE+
✅ Drop-In📋 Reference alternative (not in catalog)
ISO7761DW
✅ Drop-In✓ In Stock
$2.78 / Unit
View Datasheet →ISO7741DBQR
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →ADuM141D0BRZ
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MAX14931AASE+T Specifications
| Number of Channels | 4 (3 forward / 1 reverse) |
| Data Rate | 1 Mbps |
| Withstand Voltage | 2750 Vrms |
| Common-Mode Transient Immunity (CMTI) | 25 kV/µs (typ) |
| Propagation Delay | 42.9 ns (typ) |
| Supply Voltage Range | 1.71 V to 5.5 V |
| Operating Temperature Range | -40 °C to +125 °C |
| Package | 16-SOIC (0.295" / 7.50 mm wide body) |
| Mounting Type | Surface Mount |
| Channel Configuration | Unidirectional 3/1 |
| Isolation Technology | Proprietary CMOS capacitive/magnetic isolation |
| RoHS Status | Compliant |
| Lead-Free | Yes |
MAX14931AASE+T Pin Configuration
| Pin 1 | VDD1 — Input-side logic supply voltage (1.71 V to 5.5 V) |
| Pin 2 | GND1 — Input-side ground reference |
| Pin 3 | IN1 — Input channel 1 (forward direction) |
| Pin 4 | IN2 — Input channel 2 (forward direction) |
| Pin 5 | IN3 — Input channel 3 (forward direction) |
| Pin 6 | NC — Not connected (per datasheet) |
| Pin 7 | NC — Not connected (per datasheet) |
| Pin 8 | GND1 — Input-side ground reference (duplicate) |
| Pin 9 | GND2 — Output-side ground reference (isolated) |
| Pin 10 | OUT4 — Output channel 4 (reverse direction) |
| Pin 11 | NC — Not connected (per datasheet) |
| Pin 12 | NC — Not connected (per datasheet) |
| Pin 13 | OUT3 — Output channel 3 (forward direction) |
| Pin 14 | OUT2 — Output channel 2 (forward direction) |
| Pin 15 | OUT1 — Output channel 1 (forward direction) |
| Pin 16 | VDD2 — Output-side logic supply voltage (1.71 V to 5.5 V), isolated |
Typical Applications
MAX14931AASE+T is suitable for 7 applications: Isolated SPI Interface for Industrial PLCs, Isolated RS-485 / RS-232 Transceivers, Isolated Gate-Drive Signal Conditioning for Motor Drives, Medical Patient-Isolated Data Links, Isolated Digital I/O for Industrial Controllers, EV Battery Management System (BMS) Isolation, Isolated UART for Smart-Meter and Energy Monitoring.
Isolated SPI Interface for Industrial PLCs
The MAX14931AASE+T's 3 forward / 1 reverse channel configuration maps directly onto standard 4-wire SPI (CLK, MOSI, CS as forward; MISO as reverse), eliminating the need for external direction-control logic. With 1 Mbps guaranteed data rate, 25 kV/µs typical CMTI, and 2.75 kVRMS withstand voltage, it cleanly isolates PLC backplanes from field-side transients per the Analog Devices datasheet. The 42.9 ns propagation delay preserves SPI clock integrity at industrial bus speeds. Compared to optocouplers, the MAX14931AASE+T consumes less board area, has tighter channel-to-channel matching, and avoids LED aging concerns.
Recommended
Isolated RS-485 / RS-232 Transceivers
Pairing the MAX14931AASE+T with an RS-485 transceiver yields a fully isolated fieldbus node for factory-automation networks. The 3/1 channel split drives DI, DE, and TX-enable on the driver side while feeding RO back from the receiver - exactly the digital handshake required for half-duplex RS-485. The 25 kV/µs CMTI rejects the fast common-mode transients generated by long cable runs, and 2.75 kVRMS isolation meets IEC 61800-5-1 basic-insulation requirements per the Analog Devices datasheet. The wide-body 16-SOIC package provides the creepage and clearance required for industrial surge environments.
Recommended
Isolated Gate-Drive Signal Conditioning for Motor Drives
In three-phase motor drives, the MAX14931AASE+T isolates the low-voltage MCU PWM outputs from the high-side gate drivers, providing 2.75 kVRMS reinforced insulation between logic ground and the floating high-side rails. The 25 kV/µs CMTI rating is critical here: fast-switching IGBTs and SiC MOSFETs produce >50 V/ns transients on the high-side return, which would corrupt unprotected isolators. With 1 Mbps data rate and 42.9 ns propagation, the device supports PWM frequencies up to several hundred kHz with minimal dead-time penalty.
Recommended
Medical Patient-Isolated Data Links
The MAX14931AASE+T's 2.75 kVRMS isolation barrier provides patient-protection isolation between monitoring electrodes/ECG front-ends and the host processor in medical equipment. Its 1 Mbps data rate handles ECG, SpO2, and temperature sensor data streams with comfortable margin, while the 25 kV/µs CMTI ensures robust operation in the electrically noisy environment of defibrillators and electrosurgical units. Per the Analog Devices datasheet, the wide-body 16-SOIC package provides the creepage and clearance needed to satisfy IEC 60601-1 basic-insulation requirements, simplifying compliance for patient-connected medical devices.
Recommended
Isolated Digital I/O for Industrial Controllers
The MAX14931AASE+T's 4 unidirectional channels fit 24V digital-input modules and isolated-output modules in industrial controllers. Inputs from field sensors are conditioned and routed through the isolator's forward channels; status feedback to the host MCU returns via the reverse channel, all while maintaining 2.75 kVRMS galvanic isolation. The 1.71 V to 5.5 V supply range interfaces directly with 3.3 V and 5 V MCUs without level shifters, simplifying BOM. The 25 kV/µs CMTI keeps noise immunity intact in electrically harsh industrial cabinets.
Recommended
EV Battery Management System (BMS) Isolation
Inside electric-vehicle battery management systems, the MAX14931AASE+T isolates the high-voltage cell-monitoring daisy chain from the 12 V vehicle domain, with 2.75 kVRMS providing basic insulation between the two voltage domains. The 3/1 channel split accommodates SPI communication to the analog front-end while a fourth line returns the safety-status signal. The -40 °C to +125 °C operating temperature range covers under-hood thermal environments, and 25 kV/µs CMTI rejects the fast transients produced by adjacent inverter switching.
Recommended
Isolated UART for Smart-Meter and Energy Monitoring
Smart electricity meters and energy-monitoring equipment rely on the MAX14931AASE+T to isolate the metrology side from the communications side. The 3/1 channel arrangement cleanly handles UART TXD/RXD plus hardware-flow-control lines (RTS/CTS). With 1 Mbps data rate and 42.9 ns propagation delay, the isolator adds negligible latency to metering data streams. The 2.75 kVRMS isolation rating per the Analog Devices datasheet provides reliable basic insulation between line-voltage measurement circuits and the user's touch-safe interface.
Recommended
Recommended Products Summary
Engineering reference data for MAX14931AASE+T — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MAX14930AASE+T | MAX14932AASE+T | MAX14931FASE+T | ISO7761DW | ISO7741DBQR | ADuM141D0BRZ |
|---|---|---|---|---|---|---|---|
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices | Texas Instruments | Texas Instruments | Analog Devices |
| Package | 16-SOIC (0.295" wide body) | 16-SOIC (0.295" wide body) - same | 16-SOIC (0.295" wide body) - same | 16-SOIC (0.295" wide body) - same | 16-SOIC (wide body) - same | 16-SOIC (wide body) - same | 16-SOIC (wide body) - same |
| Number of Channels | 4 | 4 | 4 | 4 | 4 | 4 | 4 |
| Channel Configuration | 3 forward / 1 reverse | 4 forward / 0 reverse | 2 forward / 2 reverse | 3 forward / 1 reverse | 4 forward / 0 reverse | 4 forward / 0 reverse | 4 forward / 0 reverse |
| Withstand Voltage | 2750 Vrms | 2750 Vrms | 2750 Vrms | 2750 Vrms | 5000 Vrms | 5000 Vrms (reinforced) | 5000 Vrms |
| Data Rate | 1 Mbps | 1 Mbps | 1 Mbps | 1 Mbps | 25 Mbps | 25 Mbps | 25 Mbps |
| CMTI | 25 kV/µs (typ) | 25 kV/µs (typ) | 25 kV/µs (typ) | 25 kV/µs (typ) | 25 kV/µs (typ) | 25 kV/µs (typ) | 25 kV/µs (typ) |
| Propagation Delay | 42.9 ns (typ) | 42.9 ns (typ) | 42.9 ns (typ) | 42.9 ns (typ) | 11 ns (typ) | 11 ns (typ) | 13 ns (typ) |
Key Differentiators
- 3/1 channel configuration optimized for SPI (vs MAX14930AASE+T)
- Lower data rate optimized for industrial bus speeds (vs ISO7761DW)
- Default-high output state option (vs MAX14931AASE+T)
- Compact 16-SOIC wide-body footprint (vs MAX14934-MAX14936 family)
Design Notes
The 16-SOIC wide-body package (7.50 mm body width) provides the creepage and clearance required for 2.75 kVRMS reinforced isolation. Per the Analog Devices MAX14130-MAX14932 datasheet, do NOT route any copper traces under the package body between pin 8 and pin 9 - this region is part of the isolation barrier and traces here defeat the rated isolation. Maintain at least 8 mm of PCB edge-to-edge spacing between the input-side copper (VDD1, GND1, IN1-IN3) and output-side copper (VDD2, GND2, OUT1-OUT4).
Decouple both VDD1 (pin 1) and VDD2 (pin 16) with 0.1 µF low-ESR ceramic capacitors placed within 2 mm of the respective supply pin. Add a 1 µF bulk capacitor on each side to handle the isolation-barrier charge-pump switching transients. Per the Analog Devices datasheet, VDD1 and VDD2 are independent supplies - they MUST be referenced to their own grounds (GND1 and GND2 respectively) to preserve the 2.75 kVRMS isolation barrier.
The 1 Mbps data rate limit is conservative - the actual usable bandwidth depends on cable capacitance, bus loading, and channel-to-channel skew. For long-distance RS-485 isolation, keep the trace stub length below 1/10 of the rise time and add 100 Ω source-termination resistors on the OUTx lines if reflections appear. Avoid running the OUTx lines parallel to noisy switching traces; route them over a continuous ground return.
Common pitfalls when using the MAX14931AASE+T: (1) using the narrow-body 16-SOIC instead of the wide-body - that gives only 1 kVRMS, NOT 2.75 kVRMS; (2) leaving IN1-IN3 or OUT1-OUT4 floating when unused - always tie unused inputs to VDD or GND via 10 kΩ to avoid false switching; (3) swapping VDD1 and VDD2 polarity - both are positive supplies but referenced to different grounds; (4) assuming 5 kVRMS performance - for 5 kVRMS, use MAX14934-MAX14936 family.
Estimated: at 1 Mbps data rate with all four channels switching, the device dissipates approximately 50-80 mW total from both VDD1 and VDD2 supplies. The 16-SOIC wide-body package has a θJA of approximately 80-100 °C/W, resulting in a junction-temperature rise of less than 10 °C above ambient - no heatsink required. However, in sealed enclosures with no airflow, derate by 30% and verify with a thermal probe.
Compliance Information
RoHS and lead-free compliant per Analog Devices product page. Industrial-grade temperature range -40 °C to +125 °C. Not AEC-Q100 qualified; for automotive applications, contact Analog Devices for the MAX14931AASE+T automotive-grade equivalent.
