An RF signal switch circuit that allows connection of any of N radio frequency (RF) input terminals to a switch output port, either in a low loss mode, in a bypass mode, or, optionally, in a signal function mode. Embodiments of the invention allow for both a single switch in the series input path to a target circuit while still having the ability to isolate the bypass path from the target circuit. In the low loss and bypass mode, the circuit simultaneously exhibits low input insertion loss (and thus a low noise factor) and high bypass mode isolation.

The present disclosure relates to circuitry for selecting a bias voltage to output at a bias voltage output node of the circuitry. The circuitry comprises a first circuit node configured to receive a first voltage from a first, unregulated, voltage source and a second circuit node configured to receive a second voltage from a second, regulated, voltage source. A switch arrangement configured to selectively couple the bias voltage output node to the first circuit node or the second circuit node is also provided.

A switch circuit configured to receive power from either a single power source or dual power source. The circuit includes two power input terminals and two power output terminals. For a single power source, the switch circuit may receive the single power source at either of the two power input terminals. The switch circuit provides power to a load without regard to which of the power input terminals the single power source is connected. The switch circuit shorts the power output terminals for a single power input, which provides power at both power output terminals. For a dual power source system, the switch circuit may isolate the two power output terminals so each power output terminal may operate independently without shorting. In some examples, the switch circuit may be part of a thermostat or similar HVAC system controller.

A crossbar switch is disclosed having a first port, a second port, a third port, and a fourth port, the crossbar switch comprising: a first switching element coupled between the first port and the third port; a second switching element coupled between the first port and the fourth port; a third switching element coupled between the second port and the third port; and a fourth switching element coupled between the second port and the fourth port, wherein the first switching element, the second switching element, the third switching element, and the fourth switching element are configured to couple only one of the first port and the second port to the third port, at any given time.

An output stage circuit includes a first operational amplifier, a second operational amplifier, a switch circuit, a clamp circuit and at least one pull-low transistor. The first operational amplifier is operated in a first voltage domain. The second operational amplifier is operated in a second voltage domain. The switch circuit is coupled to the first operational amplifier and the second operational amplifier. The clamp circuit is coupled between the switch circuit and a plurality of output terminals of the output stage circuit. The at least one pull-low transistor is coupled to the switch circuit.

A system includes a controller that is configured to generate a plurality of switch control signals; a plurality of electrical circuit elements, the plurality of electrical circuit elements being characterized by a plurality of impedances, respectively; a plurality of voltage sources; and a plurality of switches that are programmable to couple the plurality of electrical circuit elements to the plurality of voltage sources responsive to the plurality of switch control signals.

A switch assembly includes a PIN diode connected between an antenna port and a receive port, a first shunt FET device connected between the receive port and ground, a first series FET device connected between the antenna port and a transmit port, a second shunt FET device connected between the transmit port and ground, and a plurality of bias control contacts configured to receive a corresponding plurality of bias control voltages to forward bias the first shunt FET device and the first series FET device into an ON state and to reverse bias the PIN diode and the second shunt FET device into an OFF state in a transmit mode, and to reverse bias the first shunt FET device and the first series FET device into the OFF state and to forward bias the PIN diode and the second shunt FET device into the ON state in a receive mode.

An H-bridge circuit includes a supply voltage node, a first pair of transistors and a second pair of transistors. First transistors in each pair have the current paths therethrough included in current flow lines between the supply node and, respectively, a first output node and a second output node. Second transistors in each pair have the current paths therethrough coupled to a third output node and a fourth output node, respectively. The first and third output nodes are mutually isolated from each other and the second and fourth output nodes are mutually isolated from each other. The H-bridge circuit is operable in a selected one of a first, second and third mode.

An RF signal switch circuit that allows connection of any of N radio frequency (RF) input terminals to a switch output port, either in a low loss mode, in a bypass mode, or, optionally, in a signal function mode. Embodiments of the invention allow for both a single switch in the series input path to a target circuit while still having the ability to isolate the bypass path from the target circuit. In the low loss and bypass mode, the circuit simultaneously exhibits low input insertion loss (and thus a low noise factor) and high bypass mode isolation.

A transceiver includes a receive path including a low noise amplifier and a first switch coupled between the low noise amplifier and ground, a first transmit path including a low power amplifier and a second switch coupled between the low power amplifier and a main signal path, and a second transmit path including a high power amplifier and a third switch coupled between the main signal path and ground. The receive path is active when the first, second, and third switches are in an open position, the first transmit path is active when the first switch is in a closed position, the second switch is in the closed position, and the third switch is in the open position, and the second transmit path is active when the first switch and the third switch are in the closed position, and the second switch is in the open position.