Overview
The ST3485ECDR, produced by STMicroelectronics, is a 3.3 V powered, low-power transceiver designed for RS-485 and RS-422 communication applications. This device operates in half-duplex configuration, containing one driver and one receiver. It is notable for its high-speed data transmission capability, reaching a guaranteed data rate of at least 12 Mbps. The ST3485ECDR is protected against electrostatic discharge (ESD) up to ±15 kV IEC 61000-4-2 air discharge and ±8 kV IEC 61000-4-2 contact discharge, ensuring robust performance in various environments.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (VCC) | 3 V to 3.6 V | V |
| Maximum Data Rate | 12 Mbps | Mbps |
| ESD Protection (Air Discharge) | ±15 kV | kV |
| ESD Protection (Contact Discharge) | ±8 kV | kV |
| Common Mode Input Voltage Range | -7 to 12 V | V |
| Driver Output Voltage (A, B) | ±14 V | V |
| Receiver Output Voltage (RO) | -0.3 to (VCC + 0.3) V | V |
| Shutdown Supply Current | 1 µA | µA |
| Package | SO-8 | |
| Operating Temperature Range | 0 to 70 °C | °C |
Key Features
- Operates from a single 3.3 V supply without the need for a charge pump.
- Interoperable with 5 V logic.
- Low current shutdown mode (max. 1 µA).
- Current limiting and thermal shutdown for driver overload protection.
- Guaranteed high receiver output state for floating inputs with no signal present.
- Allows up to 64 transceivers on the bus.
- Industry standard 75176 pinout.
- Half duplex versions available.
Applications
The ST3485ECDR is suitable for a variety of applications requiring high-speed RS-485 and RS-422 communication. These include industrial automation, medical devices, point-of-sale terminals, and any system that requires reliable and fast data transmission over long distances. Its robust ESD protection and thermal shutdown features make it particularly useful in environments where electrical noise and transient voltages are common.
Q & A
- What is the maximum data rate of the ST3485ECDR?
The ST3485ECDR has a guaranteed data rate of at least 12 Mbps. - What is the operating voltage range of the ST3485ECDR?
The device operates from a single 3.3 V supply. - What level of ESD protection does the ST3485ECDR offer?
The device is protected against ESD up to ±15 kV IEC 61000-4-2 air discharge and ±8 kV IEC 61000-4-2 contact discharge. - What is the common mode input voltage range for the ST3485ECDR?
The common mode input voltage range is -7 to 12 V. - How many transceivers can be connected on the same bus?
Up to 64 transceivers can be connected on the same bus. - What is the shutdown supply current of the ST3485ECDR?
The shutdown supply current is 1 µA. - What package type is the ST3485ECDR available in?
The device is available in an SO-8 package. - What is the operating temperature range of the ST3485ECDR?
The operating temperature range is 0 to 70 °C. - Is the ST3485ECDR interoperable with 5 V logic?
Yes, the device is interoperable with 5 V logic. - What protection features does the ST3485ECDR have for driver overload?
The device has current limiting and thermal shutdown for driver overload protection.
