Transformer based switches and systems for PALNA transceivers
An improved transformer based switch for PALNA applications. The transformer based switch having an input single pole port and a circuit with at least one transformer and at least one switch configured to connect portions of the transformer to ground or to short the transformer. The primary side of the transformer being connected to the input port and the secondary side of the transformer being connected to an output port.
1. A Single-Pole Single-Throw (SPST) or Single-Pole Multi-Throw (SPMT) transformer based switch configured to be connected to a power amplifier (PA) and/or Low Noise Amplifier (LNA), said transformer based switch comprising:
an input single pole port,
a circuit comprising:
a transformer having a primary and secondary winding, wherein one end of the primary winding is connected to the input single pole port and the other end is configured to be connected to a ground potential,
at least one switch connected at one end to an end of the secondary winding of the transformer, the other end of the at least one switch being either:
connected to the other end of the secondary winding, or configured to be connected to a ground potential, and
an output port comprising a first output port connected to one end of the secondary winding of the transformer and a second output port connected to the other end of the secondary winding of the transformer, and
a LNA circuit comprising:
a quarter wavelength impedance connected at one end to the input single pole port,
an LNA output port connected to the other end of the quarter wavelength impedance, and
at least one LNA circuit switch connected at one end to the LNA output port, the other end being configured to be connected to a ground potential.
2. The transformer based switch of claim 1 wherein the circuit is a PA circuit, said PA circuit comprising:
at least one positive port switch connected at one end to a positive end of the secondary winding of the transformer, the other end of the switch being configured to be connected to a ground potential, and
at least one negative port switch connected at one end to a negative end of the secondary winding of the transformer, the other end of the switch being configured to be connected to a ground potential.
3. The transformer based switch of claim 1 , wherein the switches are transistors, each transistor having a base connected to a switch port, said switch ports being configured to be connected to a switching potential.
4. The transformer based switch of claim 1 , wherein the transformer is a linear transformer.
5. The transformer based switch of claim 3 , wherein the switch ports connected to the circuit are configured to be connected to the same potential.
6. The transformer based switch of claim 3 , wherein the switch ports connected to the LNA circuit are configured to be connected to the same potential.
7. The transformer based switch of claim 3 , further comprising impedances connected between the base of at least one of the transistors and its respective switch port.
8. The transformer based switch of claim 3 , further comprising capacitors configured to be connected between each of the switch ports and a ground potential.
9. The transformer based switch of claim 1 , wherein the transformer is a center tap transformer.
10. The transformer based switch of claim 7 , wherein the impedances are selected such that they are quarter wavelength impedances.
11. A Single-Pole Single-Throw (SPST) or Single-Pole Multi-Throw (SPMT) transformer based switch configured to be connected to a power amplifier (PA) and/or Low Noise Amplifier (LNA), said transformer based switch comprising:
an input single pole port,
a circuit comprising:
a transformer having a primary and secondary winding, wherein one end of the primary winding is connected to the input single pole port and the other end is configured to be connected to a ground potential,
at least one switch connected at one end to an end of the secondary winding of the transformer, the other end of the at least one switch being either:
connected to the other end of the secondary winding, or configured to be connected to a ground potential, and
an output port comprising a first output port connected to one end of the secondary winding of the transformer and a second output port connected to the other end of the secondary winding of the transformer
a LNA circuit comprising:
a second transformer having a primary and secondary winding, wherein one end of the primary winding of the second transformer is connected to the input single pole port and the other end is configured to be connected to a ground potential,
an LNA output port comprising a first port connected to one end of the secondary winding of the second transformer and a second port connected to the other end of the secondary winding of the second transformer, and
at least one LNA circuit switch connected at one end to first port of the LNA output port the other end being connected to the second port of the LNA output port.
12. The transformer based switch of claim 11 wherein the circuit is a PA circuit, said PA circuit comprising:
at least one positive port switch connected at one end to a positive end of the secondary winding of the transformer, the other end of the switch being configured to be connected to a ground potential, and
at least one negative port switch connected at one end to a negative end of the secondary winding of the transformer, the other end of the switch being configured to be connected to a ground potential.
13. The transformer based switch of claim 11 , wherein the switches are transistors, preferably bipolar transistors, each transistor having a base connected to a switch port, said switch ports being configured to be connected to a switching potential.
14. The transformer based switch of claim 11 , wherein the transformers are linear transformers.
15. The transformer based switch of claim 11 , wherein the transformers are center tap transformers.
16. The transformer based switch of claim 13 , wherein the switch ports connected to the circuit are configured to be connected to the same potential.
17. The transformer based switch of claim 13 , wherein the switch ports connected to the LNA circuit are configured to be connected to the same potential.
18. The transformer based switch of claim 13 , further comprising impedances connected between the base of at least one of the transistors and its respective switch port.
19. The transformer based switch of claim 18 , wherein the impedances are selected such that they are quarter wavelength impedances.
20. The transformer based switch of claim 13 , further comprising capacitors configured to be connected between each of the switch ports and a ground potential.