PURPOSE: To attain low power consumption in a PLL(Phase Locked Loop) circuit and to miniaturize the whole of a receiver by providing a local oscillation circuit to balance-output an oscillation signal, the PLL circuit with a constant current operation to receive a local oscillation signal as differential input, and a mixer to receive the local oscillation signal with balance input in the same chip.
CONSTITUTION: The local oscillation signal to a PLL circuit block and the mixer 3 is set as the differential input, and the mixer 3, the local oscillation circuit 4, an I/F signal amplifier circuit 5, PLL circuit blocks 6-8 are provided on the same semiconductor substrate. In other words, effective input amplitude can be doubled by forming a programmable counter in symmetrical circuit configuration and setting the local oscillation signal as the differential input, and the loss of a signal can be reduced by providing the components in the same chip, and the normal operation of the programmable counter 6 can be performed even when the amplitude of the local oscillation signal is reduced. In such a way, a small reception circuit device having the PLL circuit block with low power consumption and a wide input band area can be obtained.
OKABE TAKEAKI
TANAKA SATOSHI
NORISUE KATSUHIRO
HITACHI VLSI ENG