A method and apparatus for dynamically monitoring, measuring, and adjusting a clock duty cycle of an operating storage device is disclosed. A storage device includes a measuring circuit comprising a plurality of flip flop registers coupled to a first input line, with each flip flop register having a first input and a second input. One or more delay taps are coupled to each flip flop register, and are disposed on a second input line. While the device operates, a clock signal is input directly into the first input of each flip flop register via the first input line. Simultaneously, the clock signal is input into the second input of each flip flop register through the one or more delay taps via the second input line. The flip flop registers are then read to determine the clock duty cycle of the device, and the clock frequency is adjusted as needed.

A method and apparatus for dynamically monitoring, measuring, and adjusting a clock duty cycle of an operating storage device is disclosed. A storage device includes a measuring circuit comprising a plurality of flip flop registers coupled to a first input line, with each flip flop register having a first input and a second input. One or more delay taps are coupled to each flip flop register, and are disposed on a second input line. While the device operates, a clock signal is input directly into the first input of each flip flop register via the first input line. Simultaneously, the clock signal is input into the second input of each flip flop register through the one or more delay taps via the second input line. The flip flop registers are then read to determine the clock duty cycle of the device, and the clock frequency is adjusted as needed.

Methods, systems, and apparatus to increase common-mode transient immunity in isolation devices is disclosed. An example apparatus includes a current mirror including an input terminal and an output terminal; a transistor including a gate terminal, a first current terminal, and a second current terminal, the gate terminal coupled to a reference voltage terminal, the first current terminal coupled to the input terminal of the current mirror, and the second current terminal coupled to an input node; a buffer including an input terminal and an output terminal, the input terminal of the buffer coupled to the output terminal of the current mirror; and a logic gate including an input terminal and an output terminal, the input terminal of the logic gate coupled to the output terminal of the buffer.

Disclosed examples include self-biased DLL circuits to generate a bias current signal proportional to a repetition frequency of a first signal representing continuous switching or discontinued switching operation of the DC-DC converter. The DLL circuit includes a monostable multivibrator to provide a pulse output signal in response to an edge of the first signal with a pulse duration set by a control current signal, a phase detector to provide output signals according to a phase difference between an edge of the pulse output signal and the first signal, and an output circuit to provide an output signal according to the phase detector output signals and according to an offset signal, to provide the bias current signal according to the output signal, and to provide the control current signal according to the output signal.

Disclosed examples include self-biased DLL circuits to generate a bias current signal proportional to a repetition frequency of a first signal representing continuous switching or discontinued switching operation of the DC-DC converter. The DLL circuit includes a monostable multivibrator to provide a pulse output signal in response to an edge of the first signal with a pulse duration set by a control current signal, a phase detector to provide output signals according to a phase difference between an edge of the pulse output signal and the first signal, and an output circuit to provide an output signal according to the phase detector output signals and according to an offset signal, to provide the bias current signal according to the output signal, and to provide the control current signal according to the output signal.

Methods, systems, and apparatus to increase common-mode transient immunity in isolation devices is disclosed. An example apparatus includes a current mirror including an input terminal and an output terminal; a transistor including a gate terminal, a first current terminal, and a second current terminal, the gate terminal coupled to a reference voltage terminal, the first current terminal coupled to the input terminal of the current mirror, and the second current terminal coupled to an input node; a buffer including an input terminal and an output terminal, the input terminal of the buffer coupled to the output terminal of the current mirror; and a logic gate including an input terminal and an output terminal, the input terminal of the logic gate coupled to the output terminal of the buffer.

Methods, systems, and apparatus to increase common-mode transient immunity in isolation devices is disclosed. An example apparatus includes a current mirror including an input terminal and an output terminal; a transistor including a gate terminal, a first current terminal, and a second current terminal, the gate terminal coupled to a reference voltage terminal, the first current terminal coupled to the input terminal of the current mirror, and the second current terminal coupled to an input node; a buffer including an input terminal and an output terminal, the input terminal of the buffer coupled to the output terminal of the current mirror; and a logic gate including an input terminal and an output terminal, the input terminal of the logic gate coupled to the output terminal of the buffer.

In accordance with an embodiment, a circuit includes a power conversion circuit including an inductor and configured to convert an input voltage to an output voltage in accordance with at least one switching signal. The circuit further includes a first current sense circuit configured to generate a current sense signal that represents an inductor current, a voltage sense circuit configured to generate a voltage sense signal that represents the output voltage, and a switching controller including an error amplifier configured to generate an error signal representing the difference between a reference voltage and the voltage sense signal. The switching controller further includes an oscillator circuit configured to generate, for pulse frequency modulation (PFM) operation of the power conversion circuit, the switching signal as a sequence of pulses with a pulse repetition frequency that depends on the error signal and the current sense signal.

In accordance with an embodiment, a circuit includes a power conversion circuit including an inductor and configured to convert an input voltage to an output voltage in accordance with at least one switching signal. The circuit further includes a first current sense circuit configured to generate a current sense signal that represents an inductor current, a voltage sense circuit configured to generate a voltage sense signal that represents the output voltage, and a switching controller including an error amplifier configured to generate an error signal representing the difference between a reference voltage and the voltage sense signal. The switching controller further includes an oscillator circuit configured to generate, for pulse frequency modulation (PFM) operation of the power conversion circuit, the switching signal as a sequence of pulses with a pulse repetition frequency that depends on the error signal and the current sense signal.

Van der Waals heterojunctions are extended to semiconducting p-type single-walled carbon nanotube (s-SWCNT) and n-type film that can be solution-processed with high spatial uniformity at the wafer scale. The resulting large-area, low-voltage p-n heterojunctions can exhibit anti-ambipolar transfer characteristics with high on/off ratios. The charge transport can be efficiently utilized in analog circuits such as frequency doublers and keying circuits that are widely used, for example, in telecommunication and wireless data transmission technologies.