A power detector with wide dynamic range. The power detector includes a linear detector, followed by a voltage-to-current-to-voltage converter, which is then followed by an amplification stage. The current-to-voltage conversion in the converter is performed logarithmically. The power detector generates a desired linear-in-dB response at the output. In this power detector, the distribution of gain along the signal path is optimized in order to preserve linearity, and to minimize the impact of offset voltage inherently present in electronic blocks, which would corrupt the output voltage. Further, the topologies in the sub-blocks are designed to provide wide dynamic range, and to mitigate error sources. Moreover, the temperature sensitivity is designed out by either minimizing temperature variation of an individual block such as the v-i-v detector, or using two sub-blocks in tandem to provide overall temperature compensation. In one aspect, active resistors are used in order to compensate for temperature variations.

A linear voltage regulator includes an error amplifier configured to receive an output voltage at an output node and a reference voltage at a reference node and output a first control voltage; a first PMOS transistor configured to receive an input voltage from a power supply node and output a first output current to the output node in accordance with the first control voltage; an AC coupling capacitor configured to couple the output voltage to an AC coupled voltage; a high-speed amplifier configured to receive the AC coupled voltage and output a second control voltage; a second PMOS transistor configured to receive the input voltage and output a second output current to the output node in accordance with the second control voltage; and a load configured to draw a load current from the output node.

A circuit includes a first transconductance stage having an output. The circuit further includes an output transconductance stage, and a first source-degenerated transistor having a first control input and first and second current terminals. The first control input is coupled to the output of the first transconductance stage. The circuit also includes a second transistor having a second control input and third and fourth current terminals. The third current terminal is coupled to the second current terminal and to the output transconductance stage.

Disclosed herein is a circuit including a differential amplifier having a pair of input transistors coupled in a differential arrangement between adjustable current sources and receiving input differential signals from a pair of input voltage regulators. The adjustable current sources are configured to source more current to the pair of input transistors than current that is sunk from the pair of input transistors. A first amplifier has inputs coupled to receive differential output voltages from the differential amplifier. A second amplifier has inputs coupled to receive amplified differential output voltages from the first amplifier. A low pass filter has inputs coupled to receive further amplified differential output voltages from the second amplifier and produce final differential output voltages.

A switched capacitor amplifier circuit includes an operational amplifier, a first capacitor and a second capacitor each having one end connected to a negative input terminal of the operational amplifier, a first switching circuit configured to connect the other end of the first capacitor and a signal source during a first operation, a second switching circuit configured to connect the other end of the second capacitor and the output terminal of the operational amplifier so as to connect the output terminal and the negative input terminal of the operational amplifier through the second capacitor during the second operation, and an impedance converter circuit configured to convert an output impedance of the signal source into a specified impedance, the impedance converter circuit being connected between the first switching circuit and the other end of the first capacitor.

A circuit includes a first transconductance stage having an output. The circuit further includes an output transconductance stage, and a first source-degenerated transistor having a first control input and first and second current terminals. The first control input is coupled to the output of the first transconductance stage. The circuit also includes a second transistor having a second control input and third and fourth current terminals. The third current terminal is coupled to the second current terminal and to the output transconductance stage.

A switched capacitor amplifier circuit includes an operational amplifier, a first capacitor and a second capacitor each having one end connected to a negative input terminal of the operational amplifier, a first switching circuit configured to connect the other end of the first capacitor and a signal source during a first operation, a second switching circuit configured to connect the other end of the second capacitor and the output terminal of the operational amplifier so as to connect the output terminal and the negative input terminal of the operational amplifier through the second capacitor during the second operation, and an impedance converter circuit configured to convert an output impedance of the signal source into a specified impedance, the impedance converter circuit being connected between the first switching circuit and the other end of the first capacitor.

An operational amplifier circuit in a display apparatus which is fast-acting to prevent voltage overshoot comprises a pre-operational amplifier module, an output operational amplifier module, and an output module. Driving current from the pre-operational amplifier module is the basis of the output operational amplifier module generating a dynamic bias voltage to the output module. The output operational amplifier module detects the dynamic bias voltage and adjusts the bias voltage to be level with a specified voltage based on at least one control voltage. When the dynamic bias voltage is less than the specified voltage, the output operational amplifier module pulls up the bias voltage and when the bias voltage is larger than the specified voltage, the output operational amplifier module pulls down the bias voltage. The pull up and pull down speeds are proportional to the at least one control voltage.

Included are a loop filter, a quantization circuit section, and a current steering digital-analog conversion section. The quantization circuit section converts a loop filter output into a digital value. The current steering digital-analog conversion section is provided in a feedback loop that feeds back the output of the quantization circuit section to the loop filter. Then, each of the analog-digital converters includes a first input signal current path, a second input signal current path, a first feedback current path, and a second feedback current path. The first input signal current path feeds a first input signal current to an input end of a first stage integrator of the loop filter. The second input signal current path feeds a second input signal current, a current opposite in sign to the first input signal current, to an input end of a second stage integrator of the loop filter. The first feedback current path connects one feedback output end of the current steering digital-analog conversion section to the input end of the first stage integrator of the loop filter. The second feedback current path connects other feedback output end of the current steering digital-analog conversion section to the input end of the second stage integrator of the loop filter.

An operational amplifier circuit in a display apparatus which is fast-acting to prevent voltage overshoot comprises a pre-operational amplifier module, an output operational amplifier module, and an output module. Driving current from the pre-operational amplifier module is the basis of the output operational amplifier module generating a dynamic bias voltage to the output module. The output operational amplifier module detects the dynamic bias voltage and adjusts the bias voltage to be level with a specified voltage based on at least one control voltage. When the dynamic bias voltage is less than the specified voltage, the output operational amplifier module pulls up the bias voltage and when the bias voltage is larger than the specified voltage, the output operational amplifier module pulls down the bias voltage. The pull up and pull down speeds are proportional to the at least one control voltage.