RF SWITCH FOR AN RF SPLITTER

• US 20110090022A1
• Filed: 06/11/2009
• Published: 04/21/2011
• Est. Priority Date: 06/13/2008
• Status: Active Grant

• Current Assignee: NXP B.V. (NXP Semiconductors NV)
• Original Assignee: NXP B.V. (NXP Semiconductors NV)
• Inventors: Villain, Frederic Francois
• Granted Patent: US 8,526,883 B2
• Time in Patent Office: Days
• US Class Current: 333/103
• CPC Class Codes: H03K 17/063 in field-effect transistor switches
• CPC Class Codes: H03K 17/6877 the control circuit comprising active elements different from those used in the output circuit
• CPC Class Codes: H04N 7/104 Switchers or splitters

Abstract

An RF switch for an RF splitter is disclosed, in which the bias voltage for the RF switching elements can be supplied, by means of an RF to DC translator, from the RF signal on the input side to the switch. By means of a native NMOS switch, routing of the RF signal is thus enabled without the necessity for an external power supply.

Claims

1. An RF switch having an input and an output and a switching element characterised by a threshold voltage therebetween, wherein the switching element comprises a native transistor.

2. An RF switch according to claim 1, further comprising an RF-to-DC-converter electrically connected to the input and being capable of supplying a bias voltage to the switching element which is greater than the threshold voltage.

3. An RF switch according to claim 1, wherein the switching element comprises an NMOS transistor.

4. An RF switch according to claim 2, wherein the RF-to-DC converter is adapted for operation without an external power supply.

5. An RF switch according to claim 4, wherein the RF-to-DC converter comprises a capacitor and diode network.

6. An RF switch according to claim 4, wherein the switching element is adapted to maintain a closed state, in the presence of an RF signal at the input and absence of external power.

7. An RF switch according to claim 1, further comprising clamping means for maintaining the switching element in an open state in the presence of external power.

8. An RF switch according to claim 7, wherein the clamping means comprises a resistor network.

9. An RF splitter including a loop-through channel having an amplifier which is arranged to be capable of being by-passed by means of an RF switch according to any preceding claim.

10. An RF splitter according to claim 9, wherein the RF switch is integrated with the amplifier.