1 Features
• IEC 61000-4-5 surge protection:
– 25A (8/20μs)
• IEC 61000-4-2 ESD protection:
– ±30kV contact discharge
– ±30kV air gap discharge
• 12V working voltage
• Bidirectional polarity to support positive and
negative voltage swings
• 2 channel device provides complete ESD/Surge
protection with single component
• Small, leaded SOT-23 allows low cost automatic
optical inspection (AOI)

2 Applications
• End equipment:
– Factory automation and control
– Building automation
– Grid infrastructure
– HVAC systems
– Security systems
• Interfaces:
– RS-485
– RS-422

3 Description
The ESDS552 is a bidirectional ESD and surge
protection diode for RS-485 and RS-422 interface
protection. The ESDS552 is rated to dissipate ESD
strikes beyond the maximum level specified in the
IEC 61000-4-2 international standard (±30kV Contact,
±30kV Air-gap). The device can clamp 8/20μs surges
with peak pulse currents up to 25A in accordance with
the IEC 61000-4-5 standard.
The low dynamic resistance and low clamping voltage
help protect systems against transient events. This
protection is key because industrial systems require a
high level of robustness and reliability.
The ESDS552 is available in a small leaded SOT-23
(DBZ) package.