Solving Random Field Resets Caused by ESD

Overview

Eliminating intermittent field failures caused by electrostatic discharge events.

Technologies

ESD | EMC | Embedded systems | PCB design

Define the Problem

A deployed system experienced sporadic resets during operation, particularly in dry environments where electrostatic discharge events were more common.

Diagnose the Root Cause

Investigation revealed transient ESD currents coupling into a high-impedance reset path, causing unintended microcontroller resets.

Key engineering challenges included:

• Intermittent field-only failures

• Difficult reproduction conditions

• Multiple potential coupling paths

• Compliance requirements

Deliver the Solution

We redesigned the reset architecture, improved transient suppression and optimised PCB return paths to improve immunity.

Key Outcomes

• Eliminated ESD-induced resets

• Passed IEC ESD testing

• Improved field robustness

• Increased system reliability