Rugged transceiver meets IEC Level 4 ESD standard
An enhanced version of the widely accepted LTC2862 ±60V tolerant RS485/RS422 transceiver that was released several years ago has been announced by Analog Devices, which recently acquired Linear Technology, the LTC2862A. Both of these half-duplex transceivers eliminate field failures without the need of costly external protection devices by protecting practical RS485 systems from installation cross-wiring faults, ground voltage faults or lightning induced surge voltages.
These faults can cause overvoltage conditions that exceed the absolute maximum ratings of typical transceivers.
Both devices operate from supply voltages of 3-5.5V while maintaining compliance with the TIA/EIA-485-A standard. However, the LTC2862A boosts its predecessor’s ESD protection and noise immunity with higher specifications including unprecedented ±40kV HBM and IEC Level 4 ESD ratings, resulting in greater robustness and signal integrity.
The LTC2862A provides valuable protection and reliability for a wide range of RS485/RS422 applications, including industrial control, instrumentation networks and automotive electronics. Whether a circuit is transmitting, receiving, in standby or powered off, the LTC2862A tolerates any voltage within ±60V without damage. An extended ±25V input common mode range increases the reliability of operation and extends functionality to environments with high common mode voltages.
Fully symmetric receiver thresholds ensure good duty cycle symmetry at low signal levels, and additional filtering prevents errors from high frequency noise, providing optimal full failsafe operation. Markedly improved ESD protection allows the LTC2862A to withstand ±40kV HBM (IEC-61000-4-2 ESD Level 4: ±8kV) on the transceiver pins without latchup or damage; all other pins are protected to ±15kV HBM. The LTC2862A also guards against electrical fast transients (EFTs) with IEC 610004-4 EFT Level 4: ±5kV protection.
The LTC2862A is offered in two data rate options: the fast 20Mbps LTC2862A-1 and the low EMI 250kbps LTC2862A-2. Both devices are offered in commercial, industrial, automotive, and military temperature grades, and available in SO-8 and 3x3mm DFN-8 packages.
- Protected from overvoltage line faults to ±60V
- 3-5.5V supply voltage
- 20Mbps or low EMI 250kbps data rate
- ±40kV HBM ESD interface pins, ±15kV other pins
- IEC Level 4 ESD & EFT on interface pins
- Enhanced receiver and failsafe noise immunity
- Extended common mode range: ±25V
- Guaranteed failsafe receiver operation
- MP-Grade option available (–55 to 125°C)
- Industry standard pinouts.