摘要:
There is provided a bias current generating apparatus capable of providing a bias current where a characteristic change is compensated, to one of an analog circuit and RF circuit where various characteristic changes occur according to a temperature, by generating bias currents having a plurality of temperature coefficients. The apparatus includes: a positive temperature coefficient current generator generating a positive temperature coefficient current in direct proportion to an absolute temperature; a zero temperature coefficient current generator generating a zero temperature coefficient current constant regardless of the absolute temperature; and an adjustable temperature coefficient current generator generating and outputting an adjustable temperature coefficient current by amplifying the positive temperature coefficient current by A times, amplifying the zero temperature coefficient current by B times, adding the two amplified temperature coefficient currents, wherein a temperature coefficient of the adjustable temperature coefficient current is varied by adjusting sizes of the A and B.
摘要:
There is provided a bias current generating apparatus capable of providing a bias current where a characteristic change is compensated, to one of an analog circuit and RF circuit where various characteristic changes occur according to a temperature, by generating bias currents having a plurality of temperature coefficients. The apparatus including: a positive temperature coefficient current generator generating a positive temperature coefficient current in direct proportion to an absolute temperature; a zero temperature coefficient current generator generating a zero temperature coefficient current constant regardless of the absolute temperature; and an adjustable temperature coefficient current generator generating and outputting an adjustable temperature coefficient current by amplifying the positive temperature coefficient current by A times, amplifying the zero temperature coefficient current by B times, adding the two amplified temperature coefficient currents, wherein a temperature coefficient of the adjustable temperature coefficient current is varied by adjusting sizes of the A and B.
摘要:
There is provided a step attenuator having two Pi-type attenuators and one bridged-T type attenuator that share some resistors. The step attenuator is used to prevent a reduction in frequency range caused by use of MOS transistors and reduce attenuation of signal power and frequency band by the MOS transistors, thereby obtaining a low attenuation value and reducing input and output mismatch.
摘要:
There is provided a step attenuator having two Pi-type attenuators and one bridged-T type attenuator that share some resistors. The step attenuator is used to prevent a reduction in frequency range caused by use of MOS transistors and reduce attenuation of signal power and frequency band by the MOS transistors, thereby obtaining a low attenuation value and reducing input and output mismatch.
摘要:
Disclosed herein is a power amplifier. The power amplifier includes a first common source transistor for amplifying an input signal into a predetermined level, a second common source transistor for compensating for input capacitance and performing auxiliary amplification for the first common source transistor, and a common gate transistor connected to the first common source transistor in a cascode structure, configured to be connected in parallel to the second common source transistor and prevent the first common source transistor from breaking down, and configured to output a signal amplified by a value obtained by adding the gain of the first common source transistor and the gain of the second common source transistor to each other.
摘要:
There is provided a complementary metal oxide semiconductor (CMOS) power amplifier including: a load unit connected between an operating voltage supply terminal and an output terminal; an amplifying unit formed as a cascode structure between the load unit and a ground, amplifying a power of an input signal input through an input terminal and outputting the amplified signal through an output terminal; and a threshold voltage control unit varying a threshold voltage of the amplifying unit according to a magnitude of the input signal input through the input terminal.
摘要:
There is provided a multi-mode power amplifier having increased isolation, including: a high power mode amplifying unit amplifying an input signal by a pre-set gain when the input signal has a power level higher than a pre-set reference level; a low power mode amplifying unit amplifying the input signal by a pre-set gain when the input signal has a power level lower than the pre-set reference level; a switch unit including one or more switches selectively proving a signal transmission path to the high power mode amplifying unit and the low power mode amplifying unit; and a controller providing a control signal having a pre-set voltage level for switching the one or more switches of the switch unit on or off, the voltage level of the control signal for switching the one or more switches off being set to be a negative voltage.
摘要:
There is provided an active balun circuit including: a load circuit unit including a first and a second load; a differential amplifying unit including a first amplifying unit connected to the first load, and a second amplifying unit connected to the second load and forming a differential amplifying unit together with the first amplifying unit, the differential amplifying unit differentially amplifying an input signal, and outputting first and second output signals out-of-phase with each other through first and second output terminals, respectively; a current source connected between a ground and a common connection node of the first and second amplifying units, and maintaining a constant amount of current flowing through the differential amplifying unit; and a compensation amplifying unit amplifying the input signal supplied through the input terminal, transmitting the amplified input signal to the second amplifying unit, and rejecting common mode noise of the differential amplifying unit.
摘要:
There is provided an active balun circuit including: a load circuit unit including a first and a second load; a differential amplifying unit including a first amplifying unit connected to the first load, and a second amplifying unit connected to the second load and forming a differential amplifying unit together with the first amplifying unit, the differential amplifying unit differentially amplifying an input signal, and outputting first and second output signals out-of-phase with each other through first and second output terminals, respectively; a current source connected between a ground and a common connection node of the first and second amplifying units, and maintaining a constant amount of current flowing through the differential amplifying unit; and a compensation amplifying unit amplifying the input signal supplied through the input terminal, transmitting the amplified input signal to the second amplifying unit, and rejecting common mode noise of the differential amplifying unit.
摘要:
A frequency conversion circuit comprises an input stage composed of one or more transistors, the input stage outputting a current corresponding to a voltage-type RF signal which is input to the gate of the transistor; a frequency conversion stage receiving an LO signal, causing the output RF signal to transit by the frequency of the LO signal so as to output an IF signal, and detecting an output voltage of the IF signal; a bleeding transistor connected to the input stage, supplying a current corresponding to a DC voltage, applied to a gate-source stage thereof, as a bleeding current to the transistor of the input stage, and in an AC manner, operating complementarily with the input stage to control a current flowing in the frequency conversion stage; a common mode feedback circuit comparing an output voltage provided from the frequency conversion stage with a preset reference voltage, adjusting the output voltage such that the output voltage is equalized to the reference voltage, and directly feeding the adjusted output voltage to the bleeding transistor; and a load stage composed of resistors and distributing a power supply voltage to apply to the frequency conversion stage.