Burr-brown Corporation

Texas Instruments Corporation

David A Heisley

Tony Ray Larson

Rodney T Burt

R Mark Stitt, Ii

Jozef C Mitros

Timothy V Kalthoff

A single-poly EEPROM memory device comprises a control gate isolated within a well of a first conductivity type in a semiconductor body of a second conductivity type, first and second tunneling regions isolated from one another within respective wells of the first conductivity type in the semiconductor body, a read transistor isolated within a well of the first conductivity type, and a floating gate overlying a portion of the control gate, the read transistor, and the first and second tunneling regions. The memory device is configured to be electrically programmed by changing a charge on the floating gate that changes the device threshold voltage. In one embodiment, the memory device is configured to be electrically programmed by applying a first potential between the first and second tunneling regions, and a second potential to the control gate, the second potential having a value less than the first potential.

Analog single-poly EEPROM incorporating two tunneling regions for programming the memory device

A low drop-out (&ldquo;LDO&rdquo;) voltage regulator includes an output stage of having a pass device and a discharge device arranged in complementary voltage follower configurations to both source load current to and sink load current from a regulated output voltage conductor. The pass device and the discharge device are controlled through a single feedback loop.

Complementary follower output stage circuitry and method for low dropout voltage regulator

An LDO voltage regulator includes an error amplifier having a first input coupled to a first reference voltage, a second input receiving a feedback signal, and an output producing a first control signal. An output transistor has a gate, a drain coupled to an unregulated input voltage, and a source coupled to produce a regulated output voltage on an output conductor. A feedback circuit is coupled between the output conductor and a second reference voltage. An overvoltage comparator has a first input coupled to receive the first reference voltage and a second input coupled to respond to the feedback signal to produce a discharge control signal indicating occurrence of an output overvoltage of at least a predetermined magnitude to control a discharge transistor coupled between the output conductor and the second reference voltage. An output current sensing circuit produces a control current representative of the drain current of the output transistor. An offset capacitor is coupled between the output of the error amplifier and the gate of the output transistor, and a servo amplifier has a first input coupled to receive a third reference voltage, a second input coupled to the output of the error amplifier, and an output coupled to the gate of the output transistor to produce a second control signal thereon. A current sensor circuit, a current capacitor, and an AND circuit operate to allow the discharge transistor to be turned on only if the output current is below a certain level.

Overvoltage sensing and correction circuitry and method for low dropout voltage regulator

A low drop out voltage regulator includes an error amplifier (,) having a first input coupled to a first reference voltage (V,), a second input receiving a feedback signal, and an output (,) producing an output signal (V,). An output transistor (,) has a gate, a drain coupled to an unregulated input voltage (V,), and a source coupled to produce a regulated output voltage (V,) on an output conductor (,). A feedback circuit (,) is coupled between the output conductor (,) and a reference voltage (GND) to produce the feedback signal. A capacitor (,) is coupled between the output (,) of the error amplifier and the gate (,) of the output transistor (,). A servo amplifier (,) has a first input coupled to a second reference voltage (VV,), a second input coupled to the output (,) of the error amplifier. A low current charge pump circuit (,B) supplies an output current into a supply voltage terminal of the servo amplifier. A variable reference voltage circuit (,) produces the second reference voltage (VV,) so as to increase the dynamic range of the voltage regulator. An output current sensing circuit (,) operates to produce a control signal (,) representative of the drain current of the output transistor (,), the variable reference voltage circuit (,) having an input coupled to receive the control signal (,).

Low dropout voltage regulator circuit including gate offset servo circuit powered by charge pump

Circuitry for reducing harmonic distortion in an amplifier includes a first transistor having a first non-linear collector-to-substrate capacitance, a first load device coupled to a collector of the first transistor, a first current source coupled to an emitter of the first transistor, a first conductor conducting an input voltage coupled to a base of the first transistor, and a second conductor coupled to the first load device and conducting an output voltage of the amplifier. The first transistor produces a first non-linear current in the first non-linear collector-to-substrate capacitance in response to the input voltage. A second transistor has a second non-linear collector-to-substrate capacitance. A second current source is coupled to an emitter of the second transistor. The first conductor is coupled to apply the input voltage to a base of the second transistor. The second transistor produces a second non-linear current in the second non-linear collector-to-substrate capacitance in response to the input voltage. A current mirror receives a collector current of the second transistor. The current mirror produces in the second conductor a correction signal substantially equal and opposite to the first non-linear current.

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Tucson, AZ, United States of America

David A Heisley