Overview
The SN65HVD31DR, produced by Texas Instruments, is a 3.3-V full-duplex RS-485 driver and receiver. This device is part of the SN65HVD3x family, designed for balanced transmission lines and compliance with ANSI TIA/EIA-485A, TIA/EIA-422-B, ITU-T v.11, and ISO 8482:1993 standards. It is suitable for various industrial and commercial applications requiring reliable and high-speed data transmission over long cable lengths.
Key Specifications
| Parameter | Test Conditions | Min | Max | Unit | |
|---|---|---|---|---|---|
| Supply Voltage (VCC) | 3 | 3.3 | 3.6 | V | |
| Operating Temperature | -40 | 85 | °C | ||
| Signaling Rate | 1 Mbps | 5 Mbps | 25 Mbps | ||
| Propagation Delay Time (tPLH) | VID = –1.5 V to 1.5 V, CL = 15 pF | 47 | 70 | ns | |
| Propagation Delay Time (tPHL) | VID = –1.5 V to 1.5 V, CL = 15 pF | 49 | 70 | ns | |
| Pulse Skew (|tPHL – tPLH|) | 10 | ns | |||
| Output Signal Rise Time (tr) | 5 | ns | |||
| Output Signal Fall Time (tf) | 6 | ns | |||
| Bus-Pin ESD Protection | 15 kV | HBM | |||
| Standby Current | Driver and receiver disabled | < 1 μA | μA |
Key Features
- 1/8 Unit-load option available, supporting up to 256 nodes on the bus.
- Bus-pin ESD protection exceeds 15 kV HBM.
- Optional driver output transition times for signaling rates of 1 Mbps, 5 Mbps, and 25 Mbps.
- Low-current standby mode with less than 1 μA current when both driver and receiver are disabled.
- Glitch-free power-up and power-down protection for hot-plugging applications.
- 5-V tolerant inputs.
- Bus idle, open, and short-circuit failsafe.
- Driver current limiting and thermal shutdown.
- Meets or exceeds the requirements of ANSI TIA/EIA-485-A and RS-422 compatible.
Applications
- Utility meters.
- DTE and DCE interfaces.
- Industrial, process, and building automation.
- Point-of-Sale (POS) systems and networks.
Q & A
- What is the operating voltage range of the SN65HVD31DR?
The operating voltage range is from 3 V to 3.6 V.
- What are the signaling rates supported by the SN65HVD31DR?
The device supports signaling rates of 1 Mbps, 5 Mbps, and 25 Mbps.
- What is the maximum number of nodes supported on the bus?
The device supports up to 256 nodes on the bus due to its 1/8 unit-load option.
- What is the ESD protection level for the bus pins?
The bus-pin ESD protection exceeds 15 kV HBM.
- How does the device handle standby mode?
The device can achieve a low standby current of less than 1 μA by disabling both the driver and receiver.
- What are the key features for power-up and power-down protection?
The device offers glitch-free power-up and power-down protection for hot-plugging applications.
- Are the inputs 5-V tolerant?
Yes, the inputs are 5-V tolerant.
- What safety features does the device have for bus conditions?
The device includes bus idle, open, and short-circuit failsafe features.
- What are the thermal characteristics of the device?
The device has thermal shutdown with a junction temperature of 170°C.
- What are some common applications for the SN65HVD31DR?
Common applications include utility meters, DTE and DCE interfaces, industrial automation, and point-of-sale systems.
