Abstract: A current threshold circuit includes a series impedance, a reference voltage source, and a comparison module. The series impedance couples an output of a current source to a load, wherein impedance of the series impedance is substantially less than impedance of the load. The reference voltage source is operably coupled to produce a reference voltage differential. The comparison module is operably coupled to compare the reference voltage differential with a differential voltage of the series impedance, wherein the comparison module generates an excessive current indication when the differential voltage of the series impedance compares unfavorably to the reference voltage differential.

Abstract: An integrated circuit for a multi-function handheld device includes a host interface, a bus, a processing module, a memory interface, a multimedia module, and a DC-to-DC converter. The host interface is operable to receive or transmit data with a host device when the multi-function handheld device is operably coupled to the host device. The processing module functions to place the multi-function handheld device in a first functional mode when the host interface is operably coupled to the host device and places the multi-function handheld device in a second functional mode when the host interface is not operably coupled to the host device. The memory interface is operably coupled to, when the multi-function handheld device is in the first functional mode, provide data received from the host device to memory for storage. The memory interface also provides data retrieved from the memory to the host interface for transmission to the host device.

Abstract: A method and apparatus for regulating multiple outputs of a single inductor DC to DC converter includes processing that begins by producing a regulation signal to regulate a 1st output of the multiple outputs based on at least one of the multiple outputs. The processing then continues by identifying one of the multiple outputs to receive energy from the inductor during at least one cycle of the regulation signal. The processing continues by scaling the regulation signal for the at least one cycle based on the voltage of the particular output to receive the energy, the voltage of the 1st output and the supply voltage to the DC to DC converter when the particular output to receive the energy is not the 1st output. In this manner, when the output receiving the energy is not the 1st output (i.e., the directly regulated output), the regulation signal is scaled based on the desired duty cycle for the particular output.

Abstract: A variable bandgap reference includes a fixed bandgap reference source and a supply voltage dependent voltage divider module. The fixed bandgap produces a fixed reference voltage. The supply voltage dependent voltage adjust module adjusts the fixed reference voltage to produce the reference voltage.

Abstract: A battery converter, which is used to convert battery voltage to an output voltage to power an integrated circuit in a battery-operated mode, is placed into a battery-charge mode to charge the battery when external power source is present to power the integrated circuit and the battery needs charging.

Abstract: An amplifier circuit uses low threshold voltage devices for mid rail response in low voltage applications, but uses a high threshold voltage device at an output stage of the amplifier to generate an output from the amplifier.

Abstract: A pulse frequency modulation unit controls upper limit level and lower limit level for an output voltage of a DC-DC converter. A voltage mode control loop uses the upper and lower limit levels in a feedback loop to generate a control signal to enable and disable the converter circuit.