Radio-frequency coil signal chain for a low-field MRI system

A switching circuit configured to be coupled to a radio-frequency (RF) coil of a low-field magnetic resonance imaging system, the switching circuit comprising:

• at least one field-effect transistor (FET) configured to operate as an RF switch at an operating frequency of less than 10 MHz;
• and
• driving circuitry configured to apply a gate voltage to the at least one FET, wherein the driving circuitry includes at least one isolation element configured to isolate a voltage source from the at least one FET, wherein the at least one isolation element comprises at least one resistor.

A switching circuit configured to be coupled to a radio-frequency (RF) coil of a low-field magnetic resonance imaging system, the switching circuit comprising:

• at least one field-effect transistor (FET) configured to operate as an RF switch at an operating frequency of less than 10 MHz;
• and
• driving circuitry configured to apply a gate voltage to the at least one FET, wherein the driving circuitry includes at least one isolation element configured to isolate a voltage source from the at least one FET, wherein the driving circuitry comprises a diode coupled between the at least one isolation element and a gate of the at least one FET, wherein the diode is configured to rectify an input AC voltage to provide a DC voltage at the gate of the at least one FET.

A switching circuit configured to be coupled to a radio-frequency (RF) coil of a low-field magnetic resonance imaging system, the switching circuit comprising:

• at least one field-effect transistor (FET) configured to operate as an RF switch at an operating frequency of less than 10 MHz;
• and
• driving circuitry configured to apply a gate voltage to the at least one FET, wherein the driving circuitry includes at least one isolation element configured to isolate a voltage source from the at least one FET, wherein the driving circuitry comprises an inductor coupled to the RF coil, wherein the inductor is configured to drive a gate of the at least one FET based on a transmit pulse sensed by the inductor.

A drive circuit configured to apply a gate voltage to at least one field-effect transistor (FET) configured to operate as a radio-frequency switch in a low-field magnetic resonance imaging system, the drive circuit comprising:

• at least one isolation element configured to isolate a voltage source from the at least one FET, wherein the at least one isolation element comprises at least one resistor.

A drive circuit configured to apply a gate voltage to at least one field-effect transistor (FET) configured to operate as a radio-frequency switch in a low-field magnetic resonance imaging system, the drive circuit comprising:

• at least one isolation element configured to isolate a voltage source from the at least one FET;
• and
• a diode coupled between the at least one isolation element and a gate of the at least one FET, wherein the diode is configured to rectify an input AC voltage to provide a DC voltage at the gate of the at least one FET.

A drive circuit configured to apply a gate voltage to at least one field-effect transistor (FET) configured to operate as a radio-frequency switch in a low-field magnetic resonance imaging system, the drive circuit comprising:

• at least one isolation element configured to isolate a voltage source from the at least one FET;
• and
• an inductor coupled to the RF coil, wherein the inductor is configured to drive a gate of the at least one FET based on a transmit pulse sensed by the inductor.