# US 2020/0403584 A1 · Transformer based switches and systems for PALNA transceivers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0403584 A1 - Document ID: US20200403584A1 - Status: Published application - Kind: A1 - Application number: 16/961,664 - Filed: 2018-12-11 - Published: 2020-12-24 - Earliest claimed: 2018-01-23 - Assignees: Teknologian tutkimuskeskus VTT Oy - Applicants: Teknologian tutkimuskeskus VTT Oy - Inventors: Mikko Varonen; Jan Saijets; Jan Holmberg - Web page: https://patentgrep.com/patent/US20200403584A1 ## CPC - H03F 3/21: with semiconductor devices only {(H03F3/245 takes precedence)} - H03F 3/19: with semiconductor devices only - H03F 3/45475: {using IC blocks as the active amplifying circuit} - H03F 2200/294: the amplifier being a low noise amplifier [LNA] - H03F 2200/534: Transformer coupled at the input of an amplifier - H03F 2200/541: Transformer coupled at the output of an amplifier - H03F 2203/45172: A transformer being added at the input of the dif amp - H03F 2203/45228: A transformer being added at the output or the load circuit of the dif amp - H03F 2203/45621: the IC comprising a transformer for phase splitting the input signal - H03F 2203/45731: the LC comprising a transformer - H03F: AMPLIFIERS ## Abstract 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. ## Claims ### Claim 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, and 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. ### Claim 2 (depends on 1) 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. ### Claim 3 (depends on 1) The transformer based switch of claim 1, further comprising: 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. ### Claim 4 (depends on 1) The transformer based switch of claim 1, further comprising: 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 transformers 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. ### Claim 5 (depends on 1) The transformer based switch of claim 1, 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. ### Claim 6 (depends on 1) The transformer based switch of claim 1, further comprising a power amplifier connected to the output port. ### Claim 7 (depends on 3) The transformer based switch of claim 3, further comprising a low noise amplifier connected to the LNA output port. ### Claim 8 (depends on 1) The transformer based switch of claim 1, wherein the transformers are linear transformers, preferably center tap transformers, more preferably center tap transformers having a center tap configured to be connected to an alternating current (AC) ground potential. ### Claim 9 (depends on 5) The transformer based switch of claim 5, wherein the switch ports connected to the PA circuit are configured to be connected to the same potential. ### Claim 10 (depends on 5) The transformer based switch of claim 5, wherein the switch ports connected to the LNA circuit are configured to be connected to the same potential. ### Claim 11 (depends on 5) The transformer based switch of claim 5, wherein the switch ports are configured to be connected to different potentials. ### Claim 12 (depends on 5) The transformer based switch of claim 5, further comprising impedances connected between the base of at least one of the transistors and its respective switch port, preferably an impedance which is selected such that it is a quarter wavelength impedance. ### Claim 13 (depends on 5) The transformer based switch of claim 5, further comprising capacitors configured to be connected between each of the switch ports and a ground potential. ### Claim 14 (depends on 2) The transformer based switch of claim 2, further comprising: 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. ### Claim 15 (depends on 2) The transformer based switch of claim 2, further comprising: 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. ### Claim 16 (depends on 2) The transformer based switch of claim 2, further comprising a power amplifier connected to the output port. ### Claim 17 (depends on 3) The transformer based switch of claim 3, further comprising a power amplifier connected to the output port. ### Claim 18 (depends on 4) The transformer based switch of claim 4, further comprising a low noise amplifier connected to the LNA output port. ### Claim 19 (depends on 14) The transformer based switch of claim 14, further comprising a low noise amplifier connected to the LNA output port. ### Claim 20 (depends on 15) The transformer based switch of claim 15, further comprising a low noise amplifier connected to the LNA output port.