Texas Instruments Corporation

Steven C Jones

Stephen C Kwan

Wayne T Chen

Keith Wolford

Taylor R Efland

Subhashish Mukherjee

Dale J Skelton

Lester L Hodson

Circular saw bracket

A DC--DC converter having an input node receiving an input voltage V.sub.IN and generating an output voltage V.sub.OUT. A reference voltage generator provides a voltage V.sub.REF and a hysteresis voltage generator provides a voltage V.sub.HYST. A first comparator generates a signal determined from a difference between V.sub.REF and V.sub.OUT. A second comparator generates a signal determined from a difference between V.sub.OUT and V.sub.HYST. A latch is coupled to receive the outputs of the first and second comparators, and to generate an output. A driver circuit receives the latch output and generates a PWM signal used to switch the output stage. A double pulse suppression circuit masks off the latch inputs for a preselected time during the switching intervals fo the main power transistors to eliminate noise jitter.

Ripple regulator with improved initial accuracy and noise immunity

A novel two-phase brushless motor drive assembly. The motor drive assembly is made of two parts, a motor assemble and a motor control circuit. The motor assembly, receives a first wire providing electric power, a second wire providing a ground connection, and a third wire. The motor assembly includes, a two-phase brushless motor. It also includes a motor drive circuit, responsive to a speed control voltage signal on the third wire and the electric power on the first wire, providing drive power to the motor to drive the motor to a speed determined by the speed control voltage signal. The motor assembly also includes a sensor circuit providing a sensed speed current signal on the third wire, having a current representing the rotational speed of the motor. The motor control circuit is coupled to the third wire, and includes a speed control circuit responsive to a speed control signal for generating the speed control voltage signal on the third wire at a voltage corresponding to a speed indicated by the speed control signal. It also includes a current sensing circuit providing a speed signal, corresponding to the sensed speed current signal on the third wire, such that the voltage of the speed control voltage signal is substantially unaffected by changes in the current of the sensed speed current signal, and such that the current of the sensed speed current signal is substantially unaffected by changes in the voltage of the speed control voltage signal.

Brushless DC motor assembly control circuit

A circuit (10) and method for protecting the gate-source elements of an FET includes a circuit (12, 13) for providing a pullup gate drive current to the gate-source elements. A voltage sensing circuit (45) senses a voltage on the gate-source elements to produce an indication if the voltage has exceeded a predetermined level. The voltage sensing circuit (45) has a zener diode (48) and a current mirror with first (52) and second (51) current flow paths. The zener diode (48) and the first flow path (52) are connected between the gate and a source of the FET. When a voltage between the gate and source of the FET exceeds the breakdown voltage of the zener diode (48) and one V.sub.gs in the current mirror, a current flows in the first flow path (52) producing a current flow in the second flow path (51). A circuit (20, 23, 62, 58, 60) reduces the pullup gate drive current in response to the current in the second flow path (51).

Method to protect gate-source elements of external power fETS from large

A single chip integrated circuit includes a boost regulated DC-to-DC converter and gate drive circuits integrated on the same die with a micro-processor, along with high density digital logic functions, analog functions, etc. The gate drive circuits are used to drive external power FETs, particularly high side NMOS. The micro-processor may also be some type of micro-controller or digital signal processor. By being able to place these functions on a single integrated circuit, a motor or actuator control system can be placed on a single chip. With appropriate sensors to provide feedback to the integrated circuit, a system which is capable of executing actuator move functions, such as position, velocity, velocity profile, torque, etc., and sequencing these events as well is included.

Micro-processor based motor control integrated circuit including a boost

A turn-off circuit is disclosed that includes a turn-off device (14) having a first current path connected to a first node, a second current path connected to a second node and an input. A control circuit (16) has an output connected to the input of the turn-off device (14) and has an input. A hold-off device (18) has an output connected to the first node and an input. Together, the turn-off device (14), the control circuit (16) and the hold-off device (18) comprise a turn-off circuit (20). A control signal CONTROL 2 is connected to the input of the control circuit (16), and a control signal CONTROL 3 is connected to the input of the hold-off device (18).

Turn-off circuit to provide a discharge path from a first node to a

An amplifier, preferably an integrated circuit, capable of accepting input common mode voltages below the circuit reference voltage or substrate voltage in the case of an integrated circuit. The amplifier comprises a differential voltage input having higher and lower voltage terminals, a first NMOS transistor coupled between a voltage supply and the higher voltage terminal and a second NMOS transistor coupled between the voltage supply and the lower voltage terminal. A third NMOS transistor is coupled between the voltage supply and the first transistor gate, a fourth NMOS transistor is coupled between the voltage supply and the second transistor gate and a sink resistor is coupled between the gate of the second transistor and the lower voltage terminal. A differential resistor is coupled between the gates of the first and second transistors. The first and second transistors include a source and a backgate coupled to each other and electrically isolated from the substrate with the source of each of the first and second transistors being coupled to a different one of the input terminals. The third and fourth transistors include a source and a backgate coupled to each other and electrically isolated from the substrate with the source of each of the third and fourth transistors coupled to opposite ends of the differential resistor. The circuit further includes a PMOS mirror circuit for providing an output.

MOS uni-directional, differential voltage amplifier capable of

A threshold detection circuit (10) is provided which comprises an input node (12) and an output node (14). The input node (12) is coupled to a current mirror (22) through a resistor (32). The current mirror (22) is further coupled to another current mirror (16), which is arranged to receive a reference current proportional to absolute temperature. The reference current is mirrored and, having been increased by a multiplier is received by a current sink (28). When the voltage level at the input node (12) exceeds a predetermined voltage threshold level, the current exceeding the amount sinkable by the current sink (28) is directed to the base of a switching transistor (30) coupled to the output node (14), and produces an output voltage level at the output node (14) indicative of the threshold voltage level being reached an/or exceeded at the input node (12). The predetermined threshold voltage may be at a level exceeding the circuit supply voltage level and is independent of ambient operating temperature.

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Garland, TX, United States of America

Steven C Jones