Overview
The ST485ECDR, produced by STMicroelectronics, is a low-power transceiver designed for RS-485 and RS-422 communication. This device is part of the ST485E series and is notable for its high level of protection and efficiency. It operates in half-duplex configuration, containing one driver and one receiver, and is optimized for bi-directional data communications on multipoint bus transmission lines. The ST485ECDR is ESD protected up to ±15 kV (HBM) and ±8 kV (IEC-1000-4-2 contact discharge), ensuring robustness against electrostatic discharge. It operates from a single 5 V supply and features low quiescent current, making it suitable for power-sensitive applications.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage | 5 V ± 5% | V |
| Operating Temperature Range | 0 to 70 °C | °C |
| ESD Protection | ±15 kV (HBM), ±8 kV (IEC-1000-4-2) | kV |
| Quiescent Current | 300 µA (typ.) | µA |
| Differential Driver Output Voltage | 1.5 to 5 V | V |
| Receiver Input Hysteresis | 70 mV | mV |
| Propagation Delay | 25 to 45 ns | ns |
| Output Skew | 2 to 5 ns | ns |
| Maximum Data Rate | 5 Mbps | Mbps |
| Package Type | SO-8 (tape and reel) |
Key Features
- Low power consumption with a quiescent current of 300 µA (typ.)
- ESD protection up to ±15 kV (HBM) and ±8 kV (IEC-1000-4-2 contact discharge)
- Operates from a single 5 V supply
- Current limiting and thermal shutdown for driver overload protection
- Driver maintains high impedance in 3-state or with power OFF
- Supports up to 256 transceivers on the bus
- High input impedance and low input current
- Fast switching times with propagation delays of 25 to 45 ns
Applications
The ST485ECDR is suitable for a variety of applications requiring reliable and efficient RS-485 and RS-422 communication. These include:
- Industrial automation and control systems
- Building automation and HVAC systems
- Medical devices and equipment
- Aerospace and defense systems
- Automotive systems requiring robust communication interfaces
- Point-of-sale terminals and other commercial equipment
Q & A
- What is the primary function of the ST485ECDR?
The ST485ECDR is a low-power transceiver for RS-485 and RS-422 communication, designed for bi-directional data communications on multipoint bus transmission lines. - What is the operating voltage range of the ST485ECDR?
The ST485ECDR operates from a single 5 V supply with a tolerance of ±5%. - What level of ESD protection does the ST485ECDR offer?
The ST485ECDR offers ESD protection up to ±15 kV (HBM) and ±8 kV (IEC-1000-4-2 contact discharge). - What is the typical quiescent current of the ST485ECDR?
The typical quiescent current is 300 µA. - What is the maximum data rate supported by the ST485ECDR?
The maximum data rate supported is 5 Mbps. - How many transceivers can be connected on the same bus?
Up to 256 transceivers can be connected on the same bus. - What is the propagation delay of the ST485ECDR?
The propagation delay is between 25 to 45 ns. - What type of package is the ST485ECDR available in?
The ST485ECDR is available in an SO-8 package, supplied in tape and reel. - What are the key protection features of the ST485ECDR?
The key protection features include current limiting, thermal shutdown, and high impedance in 3-state or with power OFF. - In what temperature range does the ST485ECDR operate?
The ST485ECDR operates in a temperature range of 0 to 70 °C.
