Switch apparatus and mobile communications terminal apparatus

• US 20050159112A1
• Filed: 03/10/2005
• Published: 07/21/2005
• Est. Priority Date: 02/19/2001
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Iida, Sachio
• Granted Patent: US 6,970,718 B2
• Time in Patent Office: Days
• US Class Current: 455/78
• CPC Class Codes: H04B 1/005 adapting radio receivers, transmitters andtransceivers for operation on two or more bands, i.e. frequency ranges
• CPC Class Codes: H04B 1/006 using switches for selecting the desired band H04B1/0057 takes precedence
• CPC Class Codes: H04B 1/406 with more than one transmission mode, e.g. analog and digital modes
• CPC Class Codes: H04B 1/48 in circuits for connecting transmitter and receiver to a common transmission path, e.g. by energy of transmitter H04B1/46 takes precedence

Abstract

A small-sized switch apparatus for switching between signal paths of at least first, second and third frequency bands is capable of handling high-powered high-frequency signals with a relatively low control voltage and is useful in a mobile terminal apparatus. A first signal terminal of a diplexer is connected to an antenna terminal, and a second signal terminal is connected to a high-frequency switch via a filter. A third signal terminal of the diplexer is connected to a high-frequency switch via a second filter. The high-frequency switch has PIN diodes as switching devices, and performs switching between a global system for mobile communications transmission signal and a global system for mobile communications reception signal. The high-frequency switch has three sets of serially connected multi-staged FETs as switching devices, and performs switching between wide-band code division multiple access transmission/reception signals, a digital cellular system transmission signal and a digital cellular system reception signal.

Claims

1-4. -4. (canceled)

5. A mobile communications terminal apparatus, comprising:

a switch apparatus for switching between signal paths and including;

a diplexer having a first signal terminal forming a transmission/reception signal terminal shared by signals of at least said first, second and third frequency bands, a second signal terminal for outputting a signal of said first frequency band separated from a received signal, a third signal terminal for outputting a remaining signal after said signal of said first frequency band is separated, wherein said received signal inputted to said first signal terminal is divided between said second and third signal terminals, and transmission signals to be inputted to said second and third signal terminals are combined and outputted to said first signal terminal;

a first high-frequency switch connected to said second signal terminal of said diplexer; and

a second high-frequency switch connected to said third signal terminal of said diplexer, wherein

said first high-frequency switch includes a plurality of switching means respectively configured with diodes for selectively switching between two signal terminals for connection to said second signal terminal of said diplexer, and

said second high-frequency switch includes at least three switching means respectively configured with FETs selectively switching between at least three signal terminals for connection to said third signal terminal of said diplexer, wherein

said first signal terminal of said diplexer of the switch apparatus is connected to an antenna;

a transmission/reception circuit for said signal of said first frequency band is connected to said two signal terminals of said first high-frequency switch;

a transmission/reception circuit for said signals of said second and third frequency bands is connected to said at least three signal terminals of said second high-frequency switch; and

short circuit means having serially connected FETs connected between one of said three signal terminals and electrical ground and having a terminal for receiving a control signal for controlling said serially connected FETs to connect said one of said three signal terminals to electrical ground.