Semiconductor integrated circuit device and wireless communication system

Abstract

The dynamic range is changed by switching a current applied to an amplifying circuit to obtain the minimum ICP required to keep linearity with the number of multiplexes even when the number of multiplexes of data is changed by switching the operation current of the amplifying circuits of the transmission system and also supplying the information about number of multiplexes of data to be transmitted to the amplifying circuits of the transmission system from the baseband circuit. Thereby, the signal can be transmitted without distortion even when the number of multiplexes increases and the current of the amplifying circuit may be reduced when the number of multiplexes is small in order to reduce the current consumption in the communication semiconductor integrated circuit device which can form a wireless communication system of the code division multiplex system such as W-CDMA system.

1 . A semiconductor integrated circuit device for wireless communication apparatus comprising: 
 modulation means for modulating multiplexed signals; and    amplification means for amplifying modulated signals from the modulation means,    wherein the amplification means receives a first control information for instructing a amplification gain and a second control information for indicating the number of multiplexes of the multiplexed signals, and    wherein a operation current of the amplification means is controlled to increase the operation current in accordance with the number of multiplexes is large or to decrease said operation current in accordance with the number of multiplexes is small.    
   
   
       2 . The semiconductor integrated circuit device for wireless communication apparatus according to  claim 1 , wherein said second control information is formed of a plurality of bits, and the operation current of the amplification means can be changed by the signal decoded the second control information.  
   
   
       3 . The semiconductor integrated circuit device for wireless communication apparatus according to  claim 2 , wherein the amplification means includes a pair of input differential transistors and a first transistor connected in series to each of the pair of input differential transistors, and 
 wherein the operation current is controlled in accordance with a current flowing into a second transistor which is connected to the first transistor with the current-Miller connection is changed by the second control information.    
   
   
       4 . The semiconductor integrated circuit device for wireless communication apparatus according to  claim 3 , wherein the amplification means comprises a plurality of resistance elements provided in parallel between emitter terminals of the pair of differential transistors and a plurality of switch elements for connecting and disconnecting the resistance elements, and the gain of the amplification means is changed when said switch elements are turned ON or OFF depending on said first control information to connect or disconnect said resistance elements.  
   
   
       5 . The semiconductor integrated circuit device for wireless communication apparatus according to  claim 3 , wherein the amplification means comprises a plurality of pairs of differential transistors provided in parallel to said pair of differential transistors, and the gain of the amplification means is varied when said plural pairs of differential transistors are connected or disconnected depending on said first control information.  
   
   
       6 . A wireless communication apparatus comprising: 
 a semiconductor integrated circuit device including a modulation means for modulating multiplexed signal, and an amplification means for amplifying modulated signals from the modulation means,    wherein the amplification means receives a first control information for instructing a amplification gain and a second control information for indicating the number of multiplexes of the multiplexed signals, and    wherein a operation current of the amplification means is controlled to increase the operation current in accordance with the number of multiplexes is large or to decrease said operation current in accordance with the number of multiplexes is small;    a baseband circuit for supplying the multiplexed signals to the modulation means; and    an electronic component including a power amplifier for amplifying the signal outputted from the semiconductor integrated circuit device, and a bias circuit for giving bias to the power amplifier in accordance with the first control information,    wherein the first control information and the second control information is supplied from the baseband circuit.