Overview
The ST485ABDR is a low power, high speed transceiver designed for RS-485 and RS-422 communications, manufactured by STMicroelectronics. This device contains one driver and one receiver in a half-duplex configuration, making it suitable for bi-directional data communications and multipoint bus transmission lines. It operates from a single 5 V supply and draws a typical supply current of 3 mA when unloaded or fully loaded with disabled drivers. The ST485ABDR features short-circuit current limiting and thermal shutdown protection for the driver, as well as a fail-safe receiver input that ensures a logic high output if both inputs are open circuit.
Key Specifications
| Parameter | Min. | Typ. | Max. | Unit |
|---|---|---|---|---|
| Supply Voltage (VCC) | 4.75 | 5 | 5.25 | V |
| Supply Current (ISUPPLY) | 2.3 | 5 | 5 | mA |
| Data Rate | 30 | - | 50 | Mbps |
| Input Hysteresis | - | 70 | - | mV |
| Common Mode Input Voltage Range | -7 | - | 12 | V |
| ESD Protection | - | ±4 | - | kV |
| Operating Temperature Range | -40 | - | 85 | °C |
| Package Type | - | SO-8 | - | - |
Key Features
- Low supply current: 5 mA max
- High data rate: > 30 Mbps
- Designed for RS-485 interface applications
- Driver maintains high impedance in 3-state or with the power off
- ±4 kV ESD protection
- Current limiting and thermal shutdown for driver overload protection
- Latch-up free up to 500 mA
- Fail-safe receiver input feature
Applications
The ST485ABDR is suitable for various applications requiring high-speed, low-power RS-485 and RS-422 communications. These include:
- Bi-directional data communications
- Multipoint bus transmission lines
- Industrial automation and control systems
- Telecommunications equipment
- Point-of-sale terminals and other commercial equipment
Q & A
- What is the typical supply current of the ST485ABDR?
The typical supply current is 3 mA when unloaded or fully loaded with disabled drivers.
- What is the maximum data rate supported by the ST485ABDR?
The maximum data rate is greater than 30 Mbps.
- What is the operating temperature range of the ST485ABDR?
The operating temperature range is from -40°C to 85°C.
- What type of package is the ST485ABDR available in?
The ST485ABDR is available in an SO-8 package.
- Does the ST485ABDR have ESD protection?
- What is the common mode input voltage range for the ST485ABDR?
The common mode input voltage range is from -7 V to 12 V.
- How does the driver protect against overload?
The driver is protected by current limiting and thermal shutdown circuitry.
- What is the fail-safe feature of the receiver input?
The fail-safe feature guarantees a logic high output if both inputs are open circuit.
- Is the ST485ABDR latch-up free?
- What are some common applications of the ST485ABDR?
