The conditions present in a typical work environment result in multiple Electrostatic Discharges (ESD) to the device on a daily basis. Some of these ESD events can cause latch-up conditions in silicon based readers that result in various unexpected currents to be drawn from the USB power source. The fingerprint reader needs to be able to handle these EDS induced latch-ups and return to normal operation in a manner that is transparent to the end user.
With no brittle and thin plastic to worry about, the Verifi series is completely built from solid aluminum offering superior strength and durability. Finishes with a highly scratch resistant powder-coated finish the casing thrives in difficult environments.
The P4000 uses an embedded microcontroller with proprietary algorithms to continuously monitor and control the incoming power from the USB connection and can instantly react to unexpected changes in voltage or current. The microcontroller communicates with the AES4000 fingerprint sensor to determine what mode it is currently in and ensures that only the proper amount of current is delivered to the sensor. If abnormal currents are detected, the microcontroller will interrupt the incoming USB connection and cycle power to the P4000. This is done in milliseconds and, if the error condition has been cleared, USB power is restored. This method allows for transparent error handling and uninterrupted operation for the end user.