Control Circuitry And Method For Controlling A Bi-Directional Switch System, A Bi-Directional Switch, A Switching Matrix And A Medical Stimulator

• US 20130009691A1
• Filed: 04/05/2011
• Published: 01/10/2013
• Est. Priority Date: 04/12/2010
• Status: Active Grant

• Current Assignee: Medtronic Bakken Research Center B.V. (Medtronic Plc)
• Original Assignee: Sapiens Steering Brain Stimulation B.V. (Medtronic Plc)
• Inventors: Blanken, Pieter Gerrit, Tol, Jeroen Jacob Arnold, Schoofs, Franciscus Adrianus Cornelis Maria, Van Goor, Dave Willem
• Granted Patent: US 8,937,504 B2
• Time in Patent Office: Days
• US Class Current: 327/425
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/36185 Selection of the electrode configuration
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H03K 17/063 in field-effect transistor switches
• CPC Class Codes: H03K 17/687 the devices being field-effect transistors

Abstract

A control circuitry (134) and a method for controlling a bi-directional switch (132) is provided. The bi-directional switch (132) having a control terminal (130) for receiving a control voltage (124) to control an on state and an off state of the bi-directional switch (132) and at least one semiconductor switch in a bi-directional main current path. The control circuitry (134) comprises an energy storage element (102), a coupling means (101) to couple the energy storage element (102) to a supply voltage to charge the energy storage element (102), and a control circuit (108) configured to receive power from the energy storage element (102) and configured to supply the control voltage having a voltage level being independent of the supply voltage when the energy storage element (102) is not coupled to the supply voltage. The coupling means (101) is configured for only coupling the 132 energy storage element (102) to the supply voltage when the bi-directional switch (132) is in the off state.

Claims

1. A control circuitry for controlling a bi-directional switch having a control terminal for receiving a control voltage to control an on state and an off state of the bi-directional switch and at least one semiconductor switch in a bi-directional main current path, the control circuitry comprises:

an energy storage element;

coupling means for coupling the energy storage element to a supply voltage for charging the energy storage element; and

a control circuit configured for receiving power from the energy storage element and configured for supplying the control voltage having a voltage level being independent of the supply voltage when the energy storage element is not coupled to the supply voltage,

wherein the coupling means is configured for only coupling the energy storage element to the supply voltage when the bi-directional switch is in the off state.

2. A control circuitry according to claim 1 further comprising a reference voltage input terminal for receiving a reference voltage,

wherein the bi-directional switch further comprises a reference voltage output terminal for providing the reference voltage indicating to which voltage level the control voltage on the control terminal has to be defined to enable switching of the bi-directional switch,

wherein the energy storage element has a first terminal and a second terminal, wherein the coupling means comprises

i) a first switch arranged between the first terminal and a first supply voltage terminal for receiving a first supply voltage,

ii) a second switch arranged between the second terminal and a second supply voltage terminal for receiving a second supply voltage, and

iii) a further control circuit for controlling at least one of the first switch and the second switch to be open or closed and being configured for only closing at least one of the first switch and the second switch when the bi-directional main current path of the bi-directional switch is in the off state, wherein, when both the first switch and the second switch are closed, the energy storage element is charged to a voltage being a difference between the first supply voltage and the second supply voltage, and wherein, when both the first switch and the second switch are open, the voltages of the first terminal and the second terminal are floating to obtain a floating state of the energy storage element, and

wherein the control circuit comprises power supply terminals being coupled between the first terminal and second terminal to receive power supply energy from the energy storage element, wherein the control voltage is generated in a floating manner when the energy storage element is in the floating state.

3. A control circuitry according to claim 2, wherein the control circuit comprises a latch for memorizing the on state or the off state of the bi-directional switch and for supplying the control voltage according to the memorized state.

4. A control circuitry according to claim 2, wherein the control circuit comprises an input terminal for receiving a switch control signal which indicates a required on or off state of the bi-directional switch.

5. A control circuitry according to claim 3,

wherein the control circuit is coupled to at least one of the first supply voltage terminal and to the second supply voltage terminal,

the input terminal is configured to receive the switch control signal which relates to at least one of the first supply voltage and the second supply voltage, and

the control circuit comprises a communication channel for communicating the bi-directional switch control signal to a floating control signal having a voltage related to the voltage of the first terminal and/or of the second terminal.

6. A control circuitry according to claims 2, wherein the latch is arranged to store the on state of the bidirectional switch in response to receiving a set signal and the off state of the bi-directional switch in response to receiving a reset signal,

the bi-directional switch control signal comprises a set sub-signal and a reset sub-signal, and

the communication channel communicates the set sub-signal and the reset sub-signal to the latch.

7. A control circuitry according to claim 1, wherein the energy storage element is a storage capacitor manufactured on basis of a MOS transistor of which the drain, the source and the backgate are electrically connected to each other, together forming a first electrode of the storage capacitor, and wherein the gate of the MOS transistor forms the second electrode of the storage capacitor.

8. A control circuitry according to claim 2, wherein the first switch or the second switch is a bootstrap diode, and the other one of the first switch and the second switch is a MOS transistor, and wherein a conducting or a non-conducting state of the MOS transistor is controlled by the further control circuit.

9. A control circuitry according to claim 2, wherein the first switch is a first MOS transistor, and the second switch is a second MOS transistor, wherein a conducting or a non-conducting state of the first MOS transistor and a conducting or a non-conducting state of the second MOS transistor is controlled by the further control circuit.

10. A bi-directional switch system comprising a bi-directional switch and the control circuitry according to claim 1.

11. A bi-directional switch system according to claim 10, wherein the bidirectional switch comprises a bi-directional main current path between a first I/O terminal and a second I/O terminal, and comprising a first MOS transistor and a second MOS transistor in the main current path, wherein the first MOS transistor and the second MOS transistor have a common source and a common gate, a drain of the first MOS transistor is coupled to the first I/O terminal, a drain of the second MOS transistor is coupled to the second I/O terminal, the common gate is coupled to a control terminal of the bidirectional switch.

12. A bi-directional switch system according to claim 11, wherein the common source is coupled to a reference voltage output terminal of the bidirectional switch.

13. A switching matrix comprising at least one bi-directional switch system as claimed in claim 10 at least one junction point of the switching matrix.

14. A medical stimulator for providing electrical stimulation signals and the medical stimulator comprising at least one bi-directional switch system according to claim 10.

15. A method of controlling a bi-directional switch having a control terminal for receiving a control voltage to control an on and off state of the bi-directional switch and at least one semiconductor switch in a bi-directional main current path, the method comprises the steps of:

coupling an energy storage element to a supply voltage only when the bi-directional switch is in the off state for charging the energy storage element;

receiving power from the energy storage element; and

supplying the control voltage having a voltage level being independent of the supply voltage when the energy storage element is not coupled to the supply voltage.