Method of transmitting information from a card reader with a power supply and wake-up circuit to a mobile device

• US 9,262,757 B2
• Filed: 11/17/2011
• Issued: 02/16/2016
• Est. Priority Date: 02/05/2002
• Status: Active Grant

• Current Assignee: Block, Inc. (f/k/a Square, Inc.)
• Original Assignee: Block, Inc. (f/k/a Square, Inc.)
• Inventors: Lamba, Kartik, Babu, Amish, Rothschild, Adam David Peter, Dorsey, Jack, McKelvey, James M.
• Primary Examiner(s): Le, Thien M
• Assistant Examiner(s): TAYLOR, APRIL ALICIA
• Application Number:
  US13/298,510
• Publication Number:
  US 20120097740A1
• Time in Patent Office: 1,552 Days
• Field of Search: 235/375, 235380-382, 235/435, 235/439, 235/449, 235/492
• US Class Current: 1/1
• CPC Class Codes: G06Q 20/30 characterised by the use of specific devices or networks
• CPC Class Codes: G06Q 20/32 using wireless devices
• CPC Class Codes: G06Q 20/322 Aspects of commerce using mobile devices [M-devices]
• CPC Class Codes: G06Q 20/3223 Realising banking transactions through M-devices
• CPC Class Codes: G06Q 20/3224 Transactions dependent on location of M-devices
• CPC Class Codes: G06Q 20/347 Passive cards
• CPC Class Codes: G06Q 30/06 Buying, selling or leasing transactions
• CPC Class Codes: G06Q 40/02 Banking, e.g. interest calculation or account maintenance credit or loans G06Q40/03
• CPC Class Codes: G07F 7/0886 the card reader being portable for interacting with a POS or ECR in realizing a payment transaction

Abstract

A method of transmitting information to a mobile device has a card reader with wake-up electronics and a microcontroller, and a power supply coupled to the wake-up electronics and the microcontroller. Data is read on the magnetic stripe. A raw magnetic signal is produced indicative of data stored on the magnetic stripe. The raw magnetic head signal is converted into a processed digital signal that the microcontroller can interpret. An output jack signal is sent to the mobile device.

Claims

1. A method of transmitting information to a mobile device, comprising:

providing a card reader with a read head that has a slot for swiping a magnetic stripe of a card, the card reader including wake-up electronics that detect when the card is being swiped in the slot, signal a microcontroller to put the device electronics into an active mode from a sleep mode and power down the wake-up electronics when the device electronics is in the active mode, and a power supply coupled to the wake-up electronics and the microcontroller;

reading data on the magnetic stripe;

producing a raw magnetic signal indicative of data stored on the magnetic stripe;

converting the raw magnetic head signal into a processed digital signal that the microcontroller can interpret; and

sending an output jack signal to the mobile device.

2. The method of claim 1, wherein the card reader includes an analog to digital front-end, the analog to digital front end being coupled to a processing element in the microcontroller.

3. The method claim 1, further comprising:

producing an encrypted output jack signal.

4. The method of claim 1, further comprising:

producing an encrypted and signed output jack signal.

5. The method of claim 1, further comprising:

producing a synchronous Manchester encoded stream output jack signal.

6. The method of claim 1, further comprising:

producing an asynchronized stream output jack signal.

7. The method of claim 1, further comprising:

producing an output jack signal at a frequency that the output jack signal appears to look AC to a microphone input of the mobile device.

8. The method of claim 1, further comprising:

producing an output jack signal at a frequency of 2 KHz to 48 kHz.

9. The method of claim 1, further comprising:

capturing card readings at the analog to digital front end that are swept at a rate of 5 inches to 50 inches per second.

10. The method of claim 1, further comprising:

sending the output jack signal to the mobile device at a constant baud rate.

11. The method of claim 10, wherein the constant baud rate is 2400 to 9200 baud.

12. The method of claim 1, wherein the analog to digital front end includes, an amplifier/filter, differentiator, a comparator and wake-up electronics.

13. The method of claim 12, further comprising:

using the wake-up electronics to signal the microcontroller, which in turn puts the device electronics back into the sleep mode when a card swipe signal stops.

14. The method of claim 13, further comprising:

powering the wake-up electronics by a microphone bias of the mobile device.

15. The method of claim 13, further comprising:

detecting by the wake-up electronics when there is an edge from leading zeros of a card being swiped and alerting to wake up the microcontroller and device electronics.

16. The method of claim 13, further comprising:

waking up the device electronics in enough time to process and encrypt a card swipe signal.

17. The method of claim 1, wherein the device electronics includes an amplifier/filter, differentiator, comparator, transmission electronics, and the microcontroller.

18. The method of claim 17, further comprising:

amplifying the raw magnetic signal by the amplifier/filter and processing before the microcontroller accepts it as an input.

19. The method of claim 18, further comprising:

taking the output of the amplifier/filter by the differentiator and differentiating it to look for peaks in the input signal.

20. The method of claim 19, further comprising:

using the comparator to take the output of the differentiator and compares it to a reference voltage and produces an output that is a processed digital version of a magnetic swipe.

21. The method of claim 20, further comprising:

using the comparator to look for where an input signal crosses zero.

22. The method of claim 21, further comprising:

using the microcontroller to accept the comparator input; and

processing the comparator input and encrypting at least a portion of data of the comparator input.

23. The method of claim 17, further comprising:

using the microcontroller to control power to the amplifier/filter, differentiator and comparator.

24. The method of claim 17, further comprising:

using the transmission electronics to accept output data of the microcontroller as an input and using this to modulate a microphone-bias line of the mobile device.

25. The method of claim 24, further comprising:

using the microphone-bias line for power and data transmission back to the mobile device.

26. The method of claim 1, further comprising:

using the microcontroller to convert raw bit patterns into formatted credit card information.

27. The method of claim 1, further comprising:

using the microcontroller to independently determine if swiped card data is valid.

28. The method of claim 1, further comprising:

accepting motion of the card bi-directionally in the slot.

29. The method of claim 1, further comprising:

accepting motion of the card at varying velocities as the card is swiped through the slot.