Abstract: Voltage regulators and methods for regulating voltages are disclosed. A switching circuit with an inductor and a plurality of switches may be used to produce a regulated voltage from an unregulated voltage source. A control circuit may be used to monitor the voltages at the input and output of the voltage regulator, and operate the switches in either a buck, boost, or buck-boost mode depending on the relationship between the voltages at the input and output of the voltage regulator.

Abstract: The present invention comprises a user-programmable control circuit for use in a power converter to automatically transition the converter into BURST mode when load current demand is low. The control circuit senses load current demand by monitoring the output current of the converter, and generating a signal representative of the monitored output current. The control circuit may automatically transition the converter into BURST mode when the signal indicative of the average monitored output current decreases below a user-programmable threshold. BURST mode may increase overall converter efficiency by turning OFF a plurality of electronic components, and maintaining the converter's output voltage at a regulated level by energy stored in an output capacitor.

Abstract: A voltage reference circuit capable of operating at reduced quiescent currents is described. The voltage reference circuit comprises an output circuit, a timer circuit and a control circuit. When in standby mode, in order to decrease power consumed by the output circuit, current through the output circuit is decreased, allowing the voltage at the output node to fall outside of a desired range. To determine when this event has occurred, the control circuit includes a test circuit that generates a test signal characterized by having a voltage that is correlated with the voltage at the output terminal.

Abstract: A slope compensation circuit that provides slope compensation signals for switching voltage regulators is provided. The slope compensation circuit includes a feedback circuit, a control circuit, and a slope signal generator circuit. The feedback circuit generates a feedback signal that is indicative of both input and output voltages. The control circuit acts as a voltage controlled resistor that varies its resistance based on the feedback signal in order to control the slope signal generator circuit so that an optimum amount of slope compensation is provided.

Abstract: A circuit breaker IC adapted for controlling an external NMOS switch coupled between a supply voltage and a load referenced to ground, with the circuit breaker being isolated from ground. With this arrangement, the voltage across the circuit breaker is limited, thereby permitting use of a low voltage integrated circuit fabrication process. The circuit breaker includes a sensor for sensing load current through the switch and providing an output signal indicative of the load current, a charge pump providing a supply voltage and an amplifier responsive to the sensor output signal and to the charge pump supply voltage for providing a drive signal to control the switch.

Abstract: A solid state circuit breaker for use in electronic devices which may be connected to an active computer bus. In one embodiment the solid state circuit breaker includes a digital to analog converter by way of which digital control signals are used to set the value at which the circuit breaker determines that a fault condition exists. Fault time is measured from when the fault condition is detected, and when the fault time exceeds a predetermined value, the circuit breaker opens, thereby preventing current flow through the circuit breaker for a second predetermined amount of time. Once this second predetermined amount of time elapses, the circuit breaker again permits current flow, and if a fault condition is determined to continue to exist, the cycle is repeated.The circuit breaker also includes a current limiting portion which restricts current flow to a maximum permissible value should the current flowing through the circuit breaker attempt to exceed this maximum permissible value.