Abstract: A LED driver IC includes a control module(s) for controlling one or more LED drive parameters and non-volatile memory for storing settings data for that control module(s). The control module(s) is fully integrated into the LED driver IC and does not require any control input from off-chip components or signals. Therefore, the space requirements for LED circuits that make use of the LED driver IC can be minimized. Also, the non-volatile memory storage of settings data eliminates the need for an initialization or configuration input each time the LED driver IC is powered on. The non-volatile memory can be a one-time programmable memory or can be a reprogrammable memory.

Abstract: A charge pump provides a programmable multiplication factor for generating an output voltage. A first output voltage may be generated by connecting a first plurality of N capacitors in a first plurality of (N+1) configurations. A second output voltage may be generated by connecting a second plurality of M capacitors in a second plurality of M+1 configurations. The first plurality of N capacitors and the second plurality of M capacitors have one or more capacitors in common. The integers M and N may be equal, although this is not required. The first plurality of configurations is different than the second plurality of configurations, thereby providing different multiplication factors for the first and second pluralities of configurations. In one embodiment, the first plurality of (N+1) configurations results in an output voltage of about 3/4× an input voltage.

Abstract: A charge pump provides a multiplication factor of ? by using a three-phase mode of operation. In a first mode, first and second capacitors are charged from an input voltage while a third capacitor drives the output voltage based on stored charge in the third capacitor. In a second mode, the output terminal is connected to the common node of the first and second capacitors. In a third mode, the voltage potential across the second capacitor is subtracted from the sum of the input voltage and the voltage potential across the first capacitor to generate the output voltage. Operated in this manner, the first, second, and third capacitors will provide the desired ?× voltage multiplication. This relatively low multiplication factor can be beneficial in applications requiring 2.5V and 1.8V supplies for integrated circuits, particularly where the input voltage is provided by a lithium battery.

Abstract: A step down switching regulator circuit that is particularly well-suited to drive high power LEDs includes a crossover conduction mode (XCM) control circuit that maintains operation at the crossover point between continuous conduction mode (CCM) and discontinuous conduction mode (DCM). This XCM operation provides an inductor current waveform that ramps up and down between zero and a desired maximum current. One or more comparators in the XCM control circuit can be used to control switching between the inductor current ramp up and ramp down phases. In this manner, complex feedback loop logic and PID controlled PWM signal generation logic can be avoided, and the need for external sense resistors and associated interface pins can be eliminated.

Abstract: A LED driver IC includes a control module(s) for controlling one or more LED drive parameters and non-volatile memory for storing settings data for that control module(s). The control module(s) is fully integrated into the LED driver IC and does not require any control input from off-chip components or signals. Therefore, the space requirements for LED circuits that make use of the LED driver IC can be minimized. Also, the non-volatile memory storage of settings data eliminates the need for an initialization or configuration input each time the LED driver IC is powered on. The non-volatile memory can be a one-time programmable memory or can be a reprogrammable memory.

Abstract: A charge pump provides a multiplication factor of 4/3 by using a three-phase mode of operation. In a first mode, first and second capacitors are charged from an input voltage while a third capacitor drives the output voltage based on stored charge in the third capacitor. In a second mode, the voltage potential across the first capacitor is added to the input voltage to generate the output voltage. In a third mode, the voltage potential across the first capacitor is subtracted from the sum of the input voltage and the voltage potential across the second capacitor to generate the output voltage. Operated in this manner, the first, second, and third capacitors will provide the desired 4/3× voltage multiplication. This relatively low multiplication factor can be beneficial in applications such as white LED driver circuits, particularly where the input voltage is provided by a battery.

Abstract: A LED driver IC includes a control module(s) for controlling one or more LED drive parameters and non-volatile memory for storing settings data for that control module(s). The control module(s) is fully integrated into the LED driver IC and does not require any control input from off-chip components or signals. Therefore, the space requirements for LED circuits that make use of the LED driver IC can be minimized. Also, the non-volatile memory storage of settings data eliminates the need for an initialization or configuration input each time the LED driver IC is powered on. The non-volatile memory can be a one-time programmable memory or can be a reprogrammable memory.