Overview
The ISO15MDW from Texas Instruments is an isolated half-duplex differential line transceiver designed for TIA/EIA RS-485 applications. This device is part of the ISO15 series, which includes the ISO15 and ISO15M models, each offering different ambient temperature ratings. The ISO15MDW is housed in a 16-pin SOIC package and provides high electromagnetic immunity and low emissions, making it suitable for environments with significant electrical noise.
This transceiver is configured for sourcing or sinking type digital inputs with minimal hardware changes, enhancing its versatility in various industrial and commercial settings. It features thermal shutdown protection, fail-safe receiver operation, and high transient immunity, ensuring reliable performance under adverse conditions.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| VCC1 Supply Voltage, Side 1 | 3.15 | 3.3 | 3.6 | V |
| VCC2 Supply Voltage, Side 2 | 3.15 | 3.3 | 3.6 | V |
| Signaling Rate | - | - | 1 Mbps | - |
| Operating Ambient Temperature (ISO15) | -40 | 25 | 85 | °C |
| Operating Ambient Temperature (ISO15M) | -55 | 25 | 125 | °C |
| Junction Temperature | - | - | 150 | °C |
| Isolation Voltage | - | - | 2500 VRMS | - |
| Differential Input Resistance | 48 kΩ | - | - | - |
| Differential Input Capacitance | - | 16 pF | - | - |
Key Features
- Meets or exceeds TIA/EIA RS-485 requirements
- 1/8 unit load – supports up to 256 nodes on a bus
- Signaling rates up to 1 Mbps
- Thermal shutdown protection
- Low bus capacitance – 16 pF (typical)
- 50 kV/μs typical transient immunity
- Fail-safe receiver for bus open, short, or idle conditions
- 3.3-V inputs are 5-V tolerant
- Safety and regulatory approvals: 4000-VPK VIOTM, 560-VPK VIORM per DIN EN IEC 60747-17, 2500 VRMS isolation rating per UL 1577 and CSA 62368-1
Applications
- Security systems
- Chemical production
- Factory automation
- Motor and motion control
- HVAC and building automation networks
- Networked security stations
Q & A
- What is the ISO15MDW used for?
The ISO15MDW is used as an isolated half-duplex differential line transceiver for TIA/EIA RS-485 applications, providing high electromagnetic immunity and low emissions.
- What are the operating temperature ranges for the ISO15 and ISO15M models?
The ISO15 operates from -40°C to 85°C, while the ISO15M operates from -55°C to 125°C.
- What is the maximum signaling rate of the ISO15MDW?
The maximum signaling rate is up to 1 Mbps.
- How many nodes can be supported on a bus with the ISO15MDW?
Up to 256 nodes can be supported due to its 1/8 unit load capability.
- What is the isolation voltage rating of the ISO15MDW?
The isolation voltage rating is 2500 VRMS.
- Does the ISO15MDW have thermal shutdown protection?
- What are the safety and regulatory approvals for the ISO15MDW?
The device has approvals for 4000-VPK VIOTM, 560-VPK VIORM per DIN EN IEC 60747-17, and 2500 VRMS isolation rating per UL 1577 and CSA 62368-1.
- What are some typical applications of the ISO15MDW?
Typical applications include security systems, chemical production, factory automation, motor and motion control, HVAC and building automation networks, and networked security stations.
- What is the differential input capacitance of the ISO15MDW?
The differential input capacitance is 16 pF (typical).
- Is the ISO15MDW 5-V tolerant on its inputs?
