Payment card with internally generated virtual account numbers for its magnetic stripe encoder and user display

A circuit for internally programming data bits beneath a magnetic stripe, comprising:

• a longitudinal magnetic stripe disposed on the surface of a substrate and providing for the retention of a sequence of magnetically recorded data bits;
• a plurality of coils each associated in parallel with corresponding ones of the sequence of magnetically recorded data bits, and embedded beneath the magnetic stripe;
• a multiplexer for selecting three adjacent coils at a time;
• a set of three capacitors to hold programming charges that are addressed through the multiplexer and discharged to said three adjacent coils in each programming step;
• and
• a sequencer to advance an address for the multiplexer and ultimately providing for a complete programming of all programmable data bits in the magnetic stripe.

A payment card system, comprising:

• a payment card with an internal virtual account number generator and a user display for online transactions;
• wherein, offline transactions with merchant card readers are enabled by a magnetic array positioned beneath a magnetic stripe on the back side;
• wherein, the internal virtual account number generator is able to program the magnetic bits encoded in the magnetic stripe to reflect a latest virtual account number, and the internal virtual account number generator produces a sequence of virtual numbers that can be predicted and approved by an issuing bank, and once a number is used, it is discarded and put on an exclusion list;
• and
• wherein, the security level of an unchanging part of the virtual account number is increased by including an expiration date field.