The present invention provides an oscillator circuit and a semiconductor integrated circuit, which can suppress the upper limit of the frequency of a clock signal due to an error of the constant current circuit. The oscillator circuit of the present invention includes a constant current circuit, an oscillator, and a current limiting circuit. The constant current circuit generates a first output current according to a supply voltage. The current limiting circuit receives the first output current and generates a second output current, and establishes an upper limit for the second output current when the supply voltage drops below a lower limit of a guaranteed operational range of the constant current circuit. The oscillator generates a clock signal according to the second output current. By establishing the upper limit for the second output current, the upper limit of the frequency of the clock signal can be suppressed.

A synchronous rectifier includes: an integrator configured to integrate a voltage across a secondary side winding of a transformer over an integral period having an expected zero integral value; a first comparator configured to detect an end of a demagnetization phase of the secondary side winding based on diode detection; and a digital circuit configured to adjust a channel gain of the synchronous rectifier based on an integration error at the end of the integral period, the integration error corresponding to the difference between the integrated voltage at the end of the integral period and the expected zero integral. Corresponding methods of gain tuning and a power converter are also described.

A device includes a substrate, a first electrode and a second electrode. The first electrode is disposed on the substrate, and configured to receive an input signal. The second electrode is disposed on the substrate, and configured to output an output signal based on the input signal. When the input signal is configured to oscillate within a first range between a first voltage value and a second voltage value with a first frequency, the output signal is an inverted version of the input signal, and has the first frequency. When the input signal is configured to oscillate within a second range including the first voltage value without the second voltage value with the first frequency, the output signal has a second frequency which is approximately twice of the first frequency.

Disclosed herein are transconductance circuits, as well as related methods and devices. In some embodiments, a transconductance circuit may include an amplifier having a first input coupled to a voltage input of the transconductance circuit, and a switch coupled between an output of the amplifier and a second input of the amplifier.

A low dropout (LDO) regulator circuit is provided. The LDO regulator circuit may include a pre-regulator circuit to receive a high voltage input voltage and provide a low voltage supply voltage, and an LDO regulator to receive the low voltage supply voltage and provide a low voltage output voltage. The pre-regulator circuit may include an input stage, an output stage coupled to the input stage, and a first MOSFET coupled to the output stage to provide the low voltage supply voltage. The input stage and first MOSFET may receive the high voltage input voltage. The LDO regulator may include a second MOSFET coupled to the first MOSFET, and may receive the low voltage supply voltage and provide the low voltage output voltage.

The present invention provides for a high voltage direct current power supply including a primary high voltage direct current supply offering a primary output; a floating secondary output floating with respect to the primary output and fed by the primary output: an output terminal at the floating secondary output for providing an output voltage; a controller operative to detect a change in the output voltage at the output terminal and to generate a control signal responsive to the change in output voltage; and a controllable current source, which can comprise a programmable current source, arranged to provide current at the floating secondary output responsive to the said control signal and whereby the said current is provided to reduce charging of a secondary output capacitance as the output voltage changes.

Voltage-to-current converters that include two current mirrors are disclosed. In an example voltage-to-current converter each current mirror is a complementary current mirror in that one of its input and output transistors is a P-type transistor and the other one is an N-type transistor. Such voltage-to-current converters may be implemented using bipolar technology, CMOS technology, or a combination of bipolar and CMOS technologies, and may be made sufficiently compact and accurate while operating at sufficiently low voltages and consuming limited power.

A control circuit for controlling a transistor includes a reference signal generating circuit and a driver stage circuit. The reference signal generating circuit outputs a reference signal, and to control the reference signal having a first change trend in a first time period of a time interval and having a second change trend in a second time period of the time interval based on time. The driver stage circuit is configured to control the transistor according to the reference signal and a current sampling signal, so that the current flowing through the transistor changes with the reference signal.

DC-DC power converter control comprises current starved delay lines for phase shifting control signals that set and reset a RS flip-flop to provide controllable PWM pulse widths from narrow to wide at a clock frequency. Precise pulse width control and a guaranteed minimum pulse width for pulse frequency modulation (PFM) control the DC-DC power converter during low power demand is also provided. PFM control maintains the same pulse width while decreasing the number of pulses per second when the output voltage exceeds an upper value and increases the number of pulses per second when the output voltage is less than a lower value. Voltage-to-current converters provide control currents to the current starved delay lines that provide the control signals to the SET and RESET inputs of the RS flip-flop. A D-flip-flop may further be used to improved circuit operation when generating high duty cycle (>50 percent) pulse widths.

A system for programming memory devices in an array is provided. The system may include a plurality of memory cells that are organized into an array having two or more rows of memory cells arranged horizontally and two or more columns of memory cells arranged vertically. The system may also include a current-compliance circuit that is electrically coupled to one or more memory cells in the plurality of memory cells. The current-compliance circuit may be configured to limit an amount of current supplied to the one or more memory cells during a programming phase of the one or more memory cells.