Low power magnetic secure transmission system

Patent metadata

Field	Value
Publication number	US-10579916-B2
Application number	US-201816028207-A
Country	US
Kind code	B2
Filing date	Jul 5, 2018
Priority date	Jul 7, 2017
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

In accordance with aspects of the present invention, a magnetic secured transmission system is presented. A magnetic secure transmission (MST) system can include a full-bridge driver that includes four transistors configured to regulate current through a coil; and a driving controller coupled to drive the full-bridge driver at a high frequency. In some embodiments, the transistors in the full bridge regulator are driven with a high frequency pulsed-wave modulated (PWM) signal to control the current through the coil. A method of magnetic secured transmission (MST) of MST data according to some embodiments includes receiving the MST data; generating coil data in response to the MST data; driving transistors in a full bridge at a high frequency to drive current through a coil according to the coil data.

First claim

What is claimed is:

1. A magnetic secure transmission (MST) system, comprising:
a full-bridge driver that includes four transistors configured to regulate current through a coil, the four transistors including a first pair of series coupled transistors in parallel with a second pair of series coupled transistors; and
a driving controller coupled to drive the full-bridge driver, the driving circuit driving each transistor of the first pair of transistors or each transistor of the second pair of transistors at a frequency higher than an MST frequency, wherein the driving controller applies first driving signals at the frequency to the first pair in response to a first MST signal and second driving signals at the frequency to the second pair in response to a second MST signal.

2. The system of claim 1 , wherein the full-bridge driver can function as an MST driver and/or a wireless power transceiver.

3. The system of claim 2 , wherein the coil can be used as a MST coil and/or a wireless power coil.

4. The system of claim 1 , wherein the driving controller can operate both pairs of the four transistors in PWM mode simultaneously.

5. The system of claim 1 , wherein the driving controller can operate the full-bridge driver in with PWM signals to interleave pairs of the four transistors.

6. The system of claim 1 , wherein the driving controller can use a PWM control method and can regulate the slew rate of a current transient through the coil.

7. The system of claim 1 , wherein the driving controller can use a PWM control method and can regulate the amplitude of current through the coil.

8. The system of claim 1 , wherein the driving controller can use a PWM control method and can regulate a power saving slope.

9. The system of claim 1 , further including a soft start method that ramps a current through the coil slowly to avoid interruptions in coil current when data transmission starts.

10. The system of claim 1 , wherein the driving controller is programmable to control slew rate, amplitude, and/or power saving slope.

11. A method of magnetic secured transmission (MST) of MST data, comprising:
receiving the MST data;
generating coil data in response to the MST data;
driving transistors in a full bridge at a high frequency greater than a frequency of the MST data to drive current through a coil according to the coil data,
wherein the transistors include a first transistor, a second transistor, a third transistor, and a fourth transistor, the first transistor and the third transistor coupled in series between a voltage and a ground, the second transistor and the fourth transistor coupled in series between the voltage and the ground, the coil being coupled between a first node between the first transistor and the third transistor and
wherein driving transistors includes driving the first transistor and the third transistor at the high frequency in response to a first coil data and driving the second transistor and the fourth transistor at the high frequency in response to a second coil data.

12. A magnetic secure transmission (MST) system, comprising:
a first transistor coupled between a voltage input and a first end connection for a MST transmit coil;
a second transistor coupled between the voltage input and a second end connection for the MST transmit coil;
a third transistor coupled between the first end connection and a ground;
a fourth transistor coupled between the second end and the ground;
a driving control circuit coupled to provide gate signals to the first transistor, the second transistor, the third transistor, and the fourth transistor to provide a high frequency switching signal, the high frequency switching signal being at a frequency greater than a frequency of a MST data; and
a transmission controller coupled to the driving circuit, the transmission controller coupled to receive MST data and determine current directions through the MST transmit coil to transmit the MST data,
wherein the driving control circuit provides first gate signals at the frequency to the first transistor and the third transistor in a first current direction and provides second gate signals at the frequency to the second transistor and the fourth transistor in a second current direction.

13. The system of claim 12 , wherein the high frequency switching is a pulsed-wave modulated (PWM) signaling to provide PWM current through MST transmit coil.

14. The system of claim 13 , wherein the on-time is adjusted to control current through the MST transmit coil.

15. The system of claim 13 , wherein a first pair of transistors formed by the first transistor and the second transistor are complementarily driven by the PWM gate signals to provide a first direction current through the transmit coil and a second pair of transistors formed by the second transistor and the fourth transistor are complementarily driven by the PWM gate signals to provide a second direction current through the transmit coil.

16. The system of claim 15 , wherein the first pair and the second pair are complementarily driven to provide the first direction current or the second direction current.

Assignees

• Integrated Device Tech

Inventors

• Liu Rui
• Qi Tao
• Zhao Lijie

Classifications

• G06Q20/347

  Passive cards · CPC title

• G06Q20/382

  insuring higher security of transaction · CPC title

• G06K19/06196 Primary

  Constructional details · CPC title

• H04B5/0031

  Electricity · mapped topic

• H04B5/26

  using coils · CPC title