Defibrillation protection devices safeguard with 100x less leakage current
Targeting medical equipment such as defibrillators, ECG diagnostics and monitoring systems, the MAX30034 defibrillation protection device from Maxim Integrated Products protects against defibrillation pulses and ESD. According to the company, it simplifies design, provides at least 75 per cent space savings, reduces the bill of materials, while significantly improving performance, compared to existing approaches and components.
Typically, defibrillators and ECG monitors are hampered by ECG input amplifiers which must withstand high-voltage pulses for cardiac resuscitation. These pulses can damage the sensitive electronic circuitry which captures the mV level heart signals. Preventing this damage has required a three-layer, multi-component approach combining a per-channel gas-discharge tube (GDT) and/or transient-voltage suppression (TVS) device, as well as ESD-protection diodes. Further, leakage current (a critical parameter) is relatively high, at about one to 2nA.
This four-channel MAX30034 defibrillation protection device uses topology from an advanced semiconductor process to absorb and harmlessly redirect these high-energy pulses away from sensitive circuitry. The small, robust device needs only two external pairs of resistors for each channel. The device also replaces the primary-level GDTs and/or TVSs, as well as secondary-level ESD diodes. Furthermore, it can withstand over 100,000 defibrillation pulses without failure and still maintain a leakage current under 10pA (100x less than GDT/TVS-based approaches).
An evaluation kit is also available.