A front-end module comprises a bias network including a current mirror, a junction temperature sensor, an n-bit analog-to-digital converter, an n-bit current source bank configured to automatically set reference current levels for one or more operating temperature regions, and a power amplifier. The bias network, junction temperature sensor, n-bit analog-to-digital converter, n-bit current source bank, and power amplifier are integrated on a first semiconductor die.

A reference voltage circuit (1) includes a PTAT voltage generation circuit (20) that generates a voltage with a positive temperature coefficient, a CTAT voltage generation circuit (10) that generates a voltage with a negative temperature coefficient, and a temperature characteristic adjustment circuit (30) that generates a voltage for adjusting temperature characteristics. The reference voltage circuit outputs a reference voltage (VOUT) formed by calculation based on the output of the PTAT voltage generation circuit, output of the CTAT voltage generation circuit, and output of the temperature characteristic adjustment circuit.

An amplification interface includes a drain of a first FET connected to a first node, a drain of a second FET connected to a second node, and sources of the first and second FETs connected to a third node. First and second bias-current generators are connected to the first and second nodes. A third FET is connected between the third node and a reference voltage. A regulation circuit drives the gate of the third FET to regulate the common mode of the voltage at the first node and the voltage at the second node to a desired value. A current generator applies a correction current to the first and/or second node. A differential current integrator has a first and second inputs connected to the second and first nodes. The integrator supplies a voltage representing the integral of the difference between the currents received at the second and first inputs.

Circuitry generates base-to-emitter voltages (Vbe1, Vbe2) of two BJTs biased at different current densities, a base-to-emitter voltage (Vbe) of a BJT biased so Vbe is complementary to absolute temperature and has a curved non-linearity across temperature, and base-to-emitter voltages (Vbe1_c, Vbe2_c) of two BJTs biased by a temperature independent constant current and a current proportional to absolute temperature so Vbe2_c−Vbe1_c has the same but opposite curved non-linearity across temperature as Vbe. A sampling circuit samples these voltages and provides them to inputs of a loop filter. Filter outputs are quantized to produce a bitstream. The sampling circuit: when the received bit of the bitstream is zero, causes integration of Vbe1−Vbe2 to produce a voltage proportional to absolute temperature (αΔVbe); and when the received bit of the bitstream is one, causes integration of Vbe2_c−Vbe_Vbe1_c to produce a negative voltage complementary to absolute temperature −Vbe_c without non-linearity across temperature.

According to one embodiment, a semiconductor device includes a first current mirror having an output end coupled to a first node, a second current mirror having an output end coupled to a second node, a third current mirror having an input end coupled to the second node and an output end coupled to the first node, a fourth current mirror having an input end coupled to the first node, and an output driver that generate a current based on the fourth current mirror. A current flows to the first current source changes at a first ratio with respect to temperature, a current flows to the second current source changes at a second ratio having a negative correlation with respect to temperature, and an absolute value of the first ratio is smaller than that of the second ratio.

A reference generator system can include a PTAT circuit coupled to a signal supply node and configured to provide a voltage reference signal or a current reference signal that is based on a physical characteristic of one or more components of the PTAT circuit and a correction signal. The system can include a CTAT circuit coupled to the PTAT circuit and configured to provide the correction signal to the PTAT circuit. In an example, the reference generator system can be implemented at least in part using NMOS devices that comprise a portion of an indium gallium zinc oxide (IGZO) substrate.

An apparatus for generating a temperature-dependent current. The apparatus includes an input current scaling circuit configured to generate a first current that varies with temperature in accordance with a first programmable slope, and a second current that varies with temperature in accordance with a second programmable slope; and a current temperature blending circuit configured to generate a third current based on the first current over a first temperature range and the second current over a second temperature range, wherein the first temperature range is different than the second temperature range.

A reference generator system can include a PTAT circuit coupled to a signal supply node and configured to provide a voltage reference signal or a current reference signal that is based on a physical characteristic of one or more components of the PTAT circuit and a correction signal. The system can include a CTAT circuit coupled to the PTAT circuit and configured to provide the correction signal to the PTAT circuit. In an example, the reference generator system can be implemented at least in part using NMOS devices that comprise a portion of an indium gallium zinc oxide (IGZO) substrate.

An electronic device includes a module that delivers a positive temperature coefficient output voltage at an output terminal. A thermistor includes a first MOS transistor operating in weak inversion mode and having a negative temperature coefficient drain-source resistance and whose source is coupled to the output terminal. A current source coupled to the output terminal operates to impose the drain-source current of the first transistor.

An electronic device includes a module that delivers a positive temperature coefficient output voltage at an output terminal. A thermistor includes a first MOS transistor operating in weak inversion mode and having a negative temperature coefficient drain-source resistance and whose source is coupled to the output terminal. A current source coupled to the output terminal operates to impose the drain-source current of the first transistor.