ISO1540D - 2.5kVrms I2C Digital Isolator | Texas Instruments
MPN: ISO1540D ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.56 | $25.60 |
| 100 | $2.28 | $228.00 |
| 500 | $2.05 | $1,025.00 |
| 1,000 | $1.82 | $1,820.00 |
Drop-in alternatives for ISO1540D — 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:
ISO1541D
✅ Drop-In📋 Reference alternative (not in catalog)
ISO1540QDQ1
✅ Drop-In📋 Reference alternative (not in catalog)
ISO1540DR
✅ Drop-In📋 Reference alternative (not in catalog)
ADUM1250ARZ
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →ISO7220ADR
✅ Drop-In📋 Reference alternative (not in catalog)
ISO1540D Maximum Ratings & Electrical Characteristics
| Isolation Voltage | 2500 Vrms |
| Number of Channels | 2 |
| Data Rate | 1 Mbps |
| CMTI | 25 kV/µs |
| Supply Voltage Range | 3 V to 5.5 V |
| Propagation Delay | 67 ns |
| Side 1 Sink Current | 3.5 mA |
| Side 2 Sink Current | 35 mA |
| Operating Temperature | -40°C to +125°C |
| Package | 8-SOIC (0.154", 3.90mm Width) |
| Mounting Type | Surface Mount |
| Output Type | Open-Drain |
| Isolation Technology | Capacitive (SiO2 barrier) |
| RoHS Status | Compliant |
| Enable Pin | Yes |
ISO1540D Pin Configuration
| Pin 1 | SDA1 — Side 1 data line (open-drain) |
| Pin 2 | SCL1 — Side 1 clock line (open-drain) |
| Pin 3 | VCC1 — Side 1 supply voltage (3V to 5.5V) |
| Pin 4 | GND1 — Side 1 ground |
| Pin 5 | GND2 — Side 2 ground |
| Pin 6 | VCC2 — Side 2 supply voltage (3V to 5.5V) |
| Pin 7 | SCL2 — Side 2 clock line (open-drain) |
| Pin 8 | SDA2 — Side 2 data line (open-drain) |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this digital IC. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
ISO1540D is suitable for 6 applications: Industrial Automation, Medical Monitoring Equipment, Battery Management Systems, Isolated Sensor Interfaces, Power Supplies and Motor Drives, Automotive Electronics.
Industrial Automation
The ISO1540D provides galvanic isolation for I2C buses in industrial automation systems, protecting control logic from high-voltage transients and ground loops. Its 2500 Vrms isolation and 25 kV/µs CMTI ensure reliable communication in noisy factory environments. The 1 Mbps data rate supports fast sensor and actuator communication, while the wide supply range (3V to 5.5V) interfaces with both 3.3V and 5V logic. The open-drain outputs with 3.5mA/35mA sink capability drive long bus traces with proper pull-up resistors. This isolator is ideal for PLCs, motor drives, and robotic controllers where isolation is critical for safety and noise immunity.
Recommended
Medical Monitoring Equipment
In medical devices, the ISO1540D ensures patient safety by isolating I2C sensor interfaces from the main control unit. Its 2500 Vrms isolation meets stringent medical safety standards, preventing leakage currents from reaching patients. The low propagation delay (67 ns) maintains real-time data integrity for vital sign monitoring. The device's -40°C to +125°C operating range suits sterilization and environmental extremes. The bidirectional I2C channels simplify design, reducing component count and board space in compact medical monitors. The open-drain outputs allow easy interfacing with various sensors, while the enable pin supports power management in battery-operated devices.
Recommended
Battery Management Systems
The ISO1540D isolates the I2C bus between battery monitoring ICs and the main controller in battery management systems (BMS). Its 2500 Vrms isolation protects low-voltage logic from high-voltage battery stacks. The 1 Mbps data rate handles real-time cell voltage and temperature monitoring. The device's low power consumption is critical for extending battery life. The bidirectional channels simplify communication with multiple battery management ICs, while the high CMTI (25 kV/µs) ensures reliable operation in the presence of switching noise from power converters. The SOIC-8 package is compact, fitting space-constrained BMS designs.
Recommended
Isolated Sensor Interfaces
The ISO1540D provides isolation for I2C-based sensors in harsh environments, such as temperature, pressure, and humidity sensors. Its 2500 Vrms isolation prevents ground loops and noise from corrupting sensor data. The 1 Mbps data rate supports high-speed sensor polling, while the 67 ns propagation delay ensures timely responses. The device's wide supply range (3V to 5.5V) allows direct interfacing with various sensor modules. The open-drain outputs with 3.5mA/35mA sink capability drive capacitive loads on long cables. The enable pin allows powering down the sensor interface when not in use, saving energy in remote or battery-powered installations.
Recommended
Power Supplies and Motor Drives
The ISO1540D isolates I2C communication between control and power stages in power supplies and motor drives. Its 2500 Vrms isolation protects low-voltage control logic from high-voltage power circuits. The high CMTI (25 kV/µs) ensures reliable operation in the presence of switching transients. The 1 Mbps data rate supports fast control loops, while the 67 ns propagation delay minimizes latency. The device's wide supply range (3V to 5.5V) interfaces with both digital controllers and analog front-ends. The bidirectional I2C channels simplify communication with power management ICs, and the SOIC-8 package is suitable for compact power modules.
Recommended
Automotive Electronics
The ISO1540D (or its Q1 variant) isolates I2C buses in automotive systems, such as battery management, infotainment, and ADAS. The 2500 Vrms isolation protects sensitive electronics from high-voltage transients in the vehicle. The 1 Mbps data rate supports real-time communication between ECUs and sensors. The device's -40°C to +125°C operating range meets automotive temperature requirements. The high CMTI (25 kV/µs) ensures reliable operation in the electrically noisy automotive environment. The bidirectional I2C channels simplify wiring, and the SOIC-8 package is robust for automotive applications. For AEC-Q100 compliance, use the ISO1540QDQ1 variant.
Recommended
Recommended Products Summary
Engineering reference data for ISO1540D — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | ISO1541D | ISO1540QDQ1 | ADUM1250ARZ |
|---|---|---|---|---|
| Package | 8-SOIC | 8-SOIC | 8-SOIC | 8-SOIC |
| Brand | Texas Instruments | Texas Instruments | Texas Instruments | Analog Devices |
| Isolation Voltage | 2500 Vrms | 2500 Vrms | 2500 Vrms | 2500 Vrms |
| Data Rate | 1 Mbps | 1 Mbps | 1 Mbps | 1 Mbps |
| CMTI | 25 kV/µs | 25 kV/µs | 25 kV/µs | 25 kV/µs |
| Propagation Delay | 67 ns | 67 ns | 67 ns | 70 ns |
| Supply Voltage Range | 3V to 5.5V | 3V to 5.5V | 3V to 5.5V | 3V to 5.5V |
| Automotive Grade | No | No | Yes (AEC-Q100) | No |
Key Differentiators
- Bidirectional I2C isolation without external direction control (vs ISO7220ADR)
- Automotive-grade variant available (vs ADUM1250ARZ)
- Lower propagation delay (vs ADUM1250ARZ)
Design Notes
Place decoupling capacitors (0.1µF) close to VCC1 and VCC2 pins to ensure stable operation. Use a solid ground plane under the device to minimize noise. Keep the isolation barrier clear of copper traces to maintain isolation integrity.
The open-drain outputs require pull-up resistors on both SDA and SCL lines. Choose resistor values based on bus capacitance and speed; for 1 Mbps, typical values are 1kΩ to 10kΩ. Ensure pull-ups are connected to the correct supply voltage on each side.
The ISO1540D dissipates minimal power, but in high-temperature environments, ensure the junction temperature stays below 150°C. The SOIC-8 package has a theta_JA of approximately 150°C/W; for most applications, no heatsinking is required.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified; use ISO1540QDQ1 for automotive.
