AMPLIFIER FOR READING SIGNALS FROM MAGNETIC CARDS Russian patent published in 2010 - IPC G11C7/06 G11B5/80 

FIELD: physics, computer engineering.

SUBSTANCE: invention relates to electronic devices and can be used in systems for reading information from bank cards with a magnetic strip with manual or automatic movement of the card, as well as cards with a magnetic strip for other purposes and devices for checking banknotes with magnetic strips. The amplifier can be used for reading signals from cards having low and high levels of coercitivity of the magnetic strip. The proposed connection of the magnetic reading head provides its optimal interfacing with amplifier cascades since it avoids the need to connect one of the outputs of the magnetic reading head to the neutral bus of the power supply, which his possible due to availability of the required dc voltage biasing at the input of the first digital inverter DD1, covered by the feedback through an electrolytic capacitor C1, whose output is connected to the first terminal of the magnetic reading head.

EFFECT: increased sensitivity of the amplification path and, as a result, widening the permissible speed range for movement of the magnetic strip relative the magnetic reading head.

3 dwg