Power detector
Disclosed is a power detector. The power detector in which calibration is performed to minimize errors caused by a process variation and a temperature variation in a structure that allows a wide input dynamic range of the power detector at a low supply voltage is provided.
1. A power detector (PD) comprising:
a PD module including a first stage, a second stage, and a third stage which receive input signals and output amplified output signals and having a structure in which the first stage and the second stage are connected in parallel and an output of the second stage is input to the third stage;
a filter having a first terminal which is connected to an output of the third stage and receives the output signal from the third stage and a second terminal which is connected to an output terminal and generates a driving signal for a specific band among the output signals; and
a calibration module having a third terminal which is connected to an output terminal of the filter and receives the driving signal from the filter and a fourth terminal which is connected to an input terminal of the PD module and feeds back a calibration signal obtained by calibrating the driving signal to the PD module,
wherein the PD module is connected to an output of the calibration module, receives and amplifies the calibration signal, and then inputs the amplified calibration signal to the first stage, and
wherein the calibration module calibrates a final code value based on sizes of a PD code value and a reference code value.
2. The PD of claim 1 , wherein:
the filter includes a second resistor, a first capacitor, and a switch, wherein the second resistor and the first capacitor are connected in series and the switch is connected in parallel to the second resistor; and
when the calibration module calibrates the driving signal according to a preset condition, the calibration module switches the switch on through control of the calibration module and makes a rising time and a falling time be as short as possible.
3. The PD of claim 2 , wherein the switch includes a first circuit in which a plurality of N-type metal-oxide-semiconductor (NMOS) transistors are connected in series and a second circuit in which a plurality of P-type metal-oxide-semiconductor (PMOS) transistors are connected in series, and has a stack structure in which the first circuit and the second circuit are connected in parallel.
4. The PD of claim 3 , wherein, in the switch, current outlet terminals of the NMOS transistors are respectively connected to current outlet terminals of the PMOS transistors, current inlet terminals of the NMOS transistors are respectively connected to current inlet terminals of the PMOS transistors, and input terminals of the NMOS transistors and input terminals of the PMOS transistors are connected to a power source.
5. The PD of claim 1 , wherein the PD module includes a third P-type amplifier, a fourth P-type amplifier, and a current source, wherein the current source receives an output of the calibration module, the current source and the fourth P-type amplifier are connected in series, and an output of the fourth P-type amplifier is input to the third P-type amplifier.
6. The PD of claim 5 , wherein the third P-type amplifier includes a third P-type input terminal, a third P-type current inlet terminal, and a third P-type current outlet terminal, wherein the third P-type input terminal is connected to a contact point of the fourth P-type amplifier and the current source, the third P-type current inlet terminal is connected to a power source, and the third P-type current outlet terminal is connected to a contact point of the first N-type amplifier and the second N-type amplifier included in the first stage.
7. The PD of claim 5 , wherein the fourth P-type amplifier includes a fourth P-type input terminal, a fourth P-type current inlet terminal, and a fourth P-type current outlet terminal, wherein the fourth P-type input terminal is connected to a power source, and the fourth P-type current inlet terminal and the fourth P-type current outlet terminal are connected to the current source.
8. The PD of claim 1 , wherein, when the PD code value is equal to the reference code value, the calibration module calibrates the final code value to have the same value as a preset temporary register value.
9. The PD of claim 1 , wherein:
when the PD code value is less than the reference code value and a preset temporary register value is not equal to 0, the calibration module subtracts 1 from the preset temporary register value; and
when the PD code value is greater than or equal to the reference code value, the calibration module calibrates a value obtained by adding 1 to the temporary register value as the final code value.
10. The PD of claim 1 , wherein:
when the PD code value is greater than the reference code value and a preset temporary register value is not equal to a preset threshold value, the calibration module adds 1 to the preset temporary register value; and
when the PD code value is less than or equal to the reference code value, the calibration module calibrates a value obtained by subtracting 1 from the temporary register value as the final code value.
11. The PD of claim 1 , wherein the PD module, the filter, and the calibration module are each implemented as a pair, and
the PD further comprising:
a power level determiner including a first PD module, a first filter, and a first calibration module among the pairs, wherein the first PD module is connected to an input terminal and determines a power level of the input signal in real time; and
a signal determiner including a second PD module, a second filter, and a second calibration module among the pairs, wherein the second PD module is connected to an alternating current (AC) ground. processes the input signal to the AC ground, and determines a state in which there is no input signal.
12. The PD of claim 11 , wherein, in the power level determiner, a terminal of the first PD module is connected to the input terminal, the other terminal of the first PD module is connected to the first filter, a terminal of the first filter is connected to an output of the first PD module, the other terminal of the first filter is connected to each of the first calibration module and an output terminal, a terminal of the first calibration module is connected to an output of the first filter, the other terminal of the first calibration module is connected to an input terminal of the first PD module, and the power level of the input signal is determined in real time.
13. The PD of claim 11 , wherein, in the signal determiner, a terminal of the second PD module is connected to the AC ground, the other terminal of the second PD module is connected to the second filter, a terminal of the second filter is connected to an output of the second PD module, the other terminal of the second filter is connected to each of the second calibration module and an output terminal, a terminal of the second calibration module is connected to an output of the second filter, the other terminal of the second calibration module is connected to an input terminal of the second PD module, and the input signal is removed.