Overview
The SN65HVD1785DRG4 is a fault-protected RS-485 transceiver manufactured by Texas Instruments. This device is designed to combine a differential driver and a differential receiver, operating from a single power supply. It is particularly robust, featuring bus-pin fault protection up to ±70 V and high levels of protection against electrostatic discharge (ESD) events. The SN65HVD1785DRG4 is suitable for half-duplex (two-wire bus) communication and is characterized over a wide temperature range of –40°C to 105°C, making it ideal for various industrial and multipoint applications over long cable runs.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Package | SOIC (D) | - |
| Pins | 8 | - |
| Operating Temperature Range | –40 to 105 | °C |
| Supply Voltage | 4.5 to 5.5 | V |
| Bus-Pin Fault Protection | ±70 | V |
| Common-Mode Voltage Range | –20 to 25 | V |
| ESD Protection | ±16 kV (JEDEC HBM) | - |
| Signaling Rate | 115 kbps | - |
| Maximum Number of Nodes | Up to 256 | - |
| Maximum Cable Length | 1500 m | - |
| Quiescent Current (ICC) | 5 mA | - |
| Standby Supply Current | 1 μA (typical) | - |
Key Features
- Bus-Pin Fault Protection up to ±70 V
- Wide Common-Mode Voltage Range (–20 V to 25 V), more than doubling TIA/EIA 485 requirements
- Bus I/O Protection and ±16 kV JEDEC HBM ESD Protection
- Reduced Unit Load for up to 256 nodes
- Failsafe Receiver for open-circuit, short-circuit, and idle-bus conditions
- Low Power Consumption with low standby supply current (1 μA typical) and quiescent current (ICC 5 mA during operation)
- Power-Up, Power-Down Glitch-Free Operation
Applications
The SN65HVD1785DRG4 is designed for use in RS-485 and RS-422 networks. It is suitable for various industrial and multipoint applications, including those requiring long cable runs. The device is also robust enough to survive overvoltage faults such as direct shorts to power supplies, mis-wiring faults, connector failures, cable crushes, and tool mis-applications, making it ideal for harsh environments.
Q & A
- What is the primary function of the SN65HVD1785DRG4?
The SN65HVD1785DRG4 is a fault-protected RS-485 transceiver that combines a differential driver and a differential receiver, operating from a single power supply.
- What is the operating temperature range of the SN65HVD1785DRG4?
The device operates over a temperature range of –40°C to 105°C.
- What level of bus-pin fault protection does the SN65HVD1785DRG4 offer?
The device offers bus-pin fault protection up to ±70 V.
- What is the common-mode voltage range of the SN65HVD1785DRG4?
The common-mode voltage range is –20 V to 25 V, more than doubling TIA/EIA 485 requirements.
- How many nodes can the SN65HVD1785DRG4 support?
The device can support up to 256 nodes.
- What is the maximum cable length supported by the SN65HVD1785DRG4?
The maximum cable length supported is 1500 meters.
- What is the quiescent current (ICC) of the SN65HVD1785DRG4 during operation?
The quiescent current (ICC) is 5 mA during operation.
- What is the standby supply current of the SN65HVD1785DRG4?
The standby supply current is 1 μA (typical).
- Does the SN65HVD1785DRG4 offer ESD protection?
Yes, the device offers ±16 kV JEDEC HBM ESD protection.
- What signaling rate does the SN65HVD1785DRG4 support?
The device supports a signaling rate of 115 kbps.
