ADUM3155BRSZ-RL7 - 7-Channel SPI Isolator 3750Vrms | Analog Devices
MPN: ADUM3155BRSZ-RL7 ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $11.06 | $11.06 |
| 10 | $10.5 | $105.00 |
| 100 | $9.95 | $995.00 |
| 500 | $9.4 | $4,700.00 |
| 1,000 | $8.85 | $8,850.00 |
ADUM3155BRSZ-RL7 Overview
A digital isolator is a component that provides electrical isolation between two circuits while allowing digital signals to pass across the isolation barrier. It is essential in applications where ground potential differences, noise, or safety requirements demand galvanic isolation. The ADUM3155BRSZ-RL7 uses Analog Devices' iCoupler chip-scale transformer technology, which offers superior performance compared to optocouplers, including higher data rates, lower power consumption, and better reliability.
Key features include a 34 Mbps data rate, 14 ns propagation delay, and 25 kV/µs CMTI, making it suitable for high-speed SPI communication in noisy industrial environments. The device supports 5 V operation on both sides (VDD1 and VDD2) and is available in a tape-and-reel package (RL7 suffix) for automated assembly.
The ADUM3155BRSZ-RL7 is part of the ADuM315x family, which includes ADuM3151, ADuM3152, and ADuM3153 variants. These devices are designed to isolate SPI buses, providing low propagation delay and high data integrity. The iCoupler technology integrates micro-transformers and high-speed CMOS circuits, ensuring robust isolation and signal integrity.
Typical applications include isolated SPI interfaces in industrial automation, motor control, data acquisition systems, and medical equipment. The device is also used in isolated power supplies and communication interfaces where ground loop isolation is critical.
When designing with this device, ensure proper PCB layout to maintain isolation spacing and minimize parasitic capacitance. The SSOP package requires careful soldering to avoid thermal stress. For high-speed operation, keep traces short and use proper termination to maintain signal integrity.
Drop-in alternatives for ADUM3155BRSZ-RL7 — 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 ADUM3155BRSZ-RL7 (same form factor and footprint) — differing in Technology, Isolation Voltage, Number of Channels, Package, Propagation Delay.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
ADUM3151BRSZ-RL7
✅ Drop-In✓ In Stock
$7.45 / Unit
View Datasheet →ADUM3152BRSZ-RL7
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.16 / Unit
View Datasheet →ADUM3153BRSZ-RL7
✅ Drop-In✓ In Stock
$3.1 / Unit
View Datasheet →ADUM3154BRIZ
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
ADUM4154BRIZ
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.16 / Unit
View Datasheet →ADUM3155BRSZ-RL7 Specifications
| Isolation Voltage | 3750 Vrms |
| Number of Channels | 7 |
| Data Rate | 34 Mbps |
| CMTI | 25 kV/µs |
| Propagation Delay | 14 ns |
| Supply Voltage (VDD1) | 4.5 V to 5.5 V |
| Supply Voltage (VDD2) | 4.5 V to 5.5 V |
| Operating Temperature | -40°C to +125°C |
| Package | 20-SSOP (0.209", 5.30mm Width) |
| Mounting Type | Surface Mount |
| Technology | iCoupler |
| SPI Clock Rate | 17 MHz |
| RoHS Status | Compliant |
| Qualification | Industrial |
ADUM3155BRSZ-RL7 Pin Configuration
| Pin 1 | VDD1 — Supply voltage side 1 |
| Pin 2 | GND1 — Ground side 1 |
| Pin 3 | CLK — SPI clock input |
| Pin 4 | MO/SI — Master out/slave in |
| Pin 5 | MI/SO — Master in/slave out |
| Pin 6 | SS — Slave select |
| Pin 7 | GND1 — Ground side 1 |
| Pin 8 | VDD1 — Supply voltage side 1 |
| Pin 9 | NC — No connect |
| Pin 10 | NC — No connect |
| Pin 11 | VDD2 — Supply voltage side 2 |
| Pin 12 | GND2 — Ground side 2 |
| Pin 13 | CLK2 — Isolated clock output |
| Pin 14 | MO/SI2 — Isolated data output |
| Pin 15 | MI/SO2 — Isolated data input |
| Pin 16 | SS2 — Isolated slave select |
| Pin 17 | GND2 — Ground side 2 |
| Pin 18 | VDD2 — Supply voltage side 2 |
| Pin 19 | NC — No connect |
| Pin 20 | NC — No connect |
Typical Applications
ADUM3155BRSZ-RL7 is suitable for 6 applications: Industrial Automation, Motor Control, Data Acquisition Systems, Medical Equipment, Isolated Power Supplies, Communication Interfaces.
Industrial Automation
The ADUM3155BRSZ-RL7 provides isolated SPI communication in industrial automation systems, ensuring reliable data transfer between controllers and sensors in noisy environments. Its 3750 Vrms isolation and 25 kV/µs CMTI protect against ground loops and transient voltages, while the 34 Mbps data rate supports high-speed control loops. The device operates over -40°C to +125°C, making it suitable for harsh factory floors.
Recommended
Motor Control
In motor control applications, the ADUM3155BRSZ-RL7 isolates the SPI interface between the microcontroller and gate driver or encoder. The low 14 ns propagation delay ensures precise timing for PWM signals, while the high CMTI prevents false triggering from motor-induced transients. The 5 V operation simplifies power supply design, and the SSOP package fits compact drive modules.
Recommended
Data Acquisition Systems
The ADUM3155BRSZ-RL7 is used in data acquisition systems to isolate the ADC from the host controller, preventing ground noise from corrupting measurements. Its 34 Mbps data rate allows high-speed sampling, and the 3750 Vrms isolation protects sensitive analog circuits from high-voltage transients. The device supports SPI clock rates up to 17 MHz, ensuring compatibility with high-resolution ADCs.
Recommended
Medical Equipment
In medical equipment, the ADUM3155BRSZ-RL7 provides galvanic isolation for patient safety, isolating SPI interfaces in monitoring devices and diagnostic instruments. The 3750 Vrms isolation meets stringent safety standards, while the low propagation delay ensures real-time data transmission. The wide temperature range and high reliability make it suitable for critical medical applications.
Recommended
Isolated Power Supplies
The ADUM3155BRSZ-RL7 is used in isolated power supplies to communicate control signals across the isolation barrier. Its high CMTI ensures stable operation in the presence of switching noise, and the 34 Mbps data rate supports fast feedback loops. The device's low power consumption helps maintain efficiency in power supply designs.
Recommended
Communication Interfaces
The ADUM3155BRSZ-RL7 is employed in communication interfaces to isolate SPI buses between boards or systems, preventing ground loops and reducing noise. Its 3750 Vrms isolation and 25 kV/µs CMTI make it robust for industrial communication networks. The device supports high-speed data transfer, ensuring minimal latency in real-time systems.
Recommended
Recommended Products Summary
Engineering reference data for ADUM3155BRSZ-RL7 — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ADUM3151BRSZ-RL7 | ADUM3152BRSZ-RL7 | ADUM3153BRSZ-RL7 |
|---|---|---|---|---|
| Package | 20-SSOP | 20-SSOP | 20-SSOP | 20-SSOP |
| Brand | Analog Devices | Analog Devices | Analog Devices | Analog Devices |
| Isolation Voltage | 3750 Vrms | 3750 Vrms | 3750 Vrms | 3750 Vrms |
| Data Rate | 34 Mbps | 34 Mbps | 34 Mbps | 34 Mbps |
| CMTI | 25 kV/µs | 25 kV/µs | 25 kV/µs | 25 kV/µs |
| Propagation Delay | 14 ns | 14 ns | 14 ns | 14 ns |
| Supply Voltage | 4.5V to 5.5V | 4.5V to 5.5V | 4.5V to 5.5V | 4.5V to 5.5V |
| Operating Temperature | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C | -40°C to +125°C |
Key Differentiators
- High data rate of 34 Mbps (vs ADUM3151BRSZ-RL7)
- Low propagation delay of 14 ns (vs ADUM3152BRSZ-RL7)
- High CMTI of 25 kV/µs (vs ADUM3153BRSZ-RL7)
Design Notes
Maintain proper isolation spacing on the PCB. The ADUM3155BRSZ-RL7 provides 3750 Vrms isolation, so the creepage and clearance distances between the two sides must meet safety standards. Use a slot or cutout under the device to increase the isolation distance if needed.
Keep the SPI signal traces short and balanced to minimize propagation delay and signal skew. The 14 ns propagation delay is low, but mismatched trace lengths can cause timing errors. Use ground planes on both sides of the isolation barrier to reduce noise coupling.
Decouple both VDD1 and VDD2 with 0.1 µF and 10 µF capacitors placed close to the pins. The device operates from 4.5V to 5.5V, and stable power is essential for reliable isolation. Avoid sharing the same power supply without proper filtering to prevent noise coupling across the barrier.
Compliance Information
RoHS compliant per distributor data. Other compliance information not specified in provided data.