Abstract: A phase locked loop (PLL) circuit having a deadlock protection circuit and a deadlock protection method of the PLL circuit are provided.

Abstract: A system and method are provided herein for monitoring the integrity of a power supply by monitoring a level of the power supply voltage supplied to one or more system components. The method, as described herein, includes setting a bit in a status register after the power supply level reaches a threshold level, and monitoring a state of the bit to determine if the power supply level has dropped below the threshold level. For example, the method may determine that the power supply level has dropped below the threshold level if the state of the bit changes from a set bit to a cleared bit. In addition, the system and method described herein may be used for detecting the occurrence of a power abnormality by providing additional resources/information about a power related event.

Abstract: A voltage translator circuit and a method for operating the same. The voltage translator circuit includes (a) an input node, an output node, and a ground node; (b) a voltage divider circuit including a first and second resistors coupled in series between the input node and the ground node; (c) a start voltage circuit coupled to a first voltage and to the input node; (d) a transfer circuit coupled to the output node; and (e) a capacitive circuit having a first and second capacitive nodes. The first capacitive node is coupled to the voltage divider circuit. The second capacitive node is coupled (i) to the first voltage via the start voltage circuit, and (ii) to the output node via the transfer circuit. In response to the input node changing towards the first voltage, the start voltage circuit is capable of disconnecting the second capacitive node from the first voltage.

Abstract: A digital delay locked loop architecture is independent of feedback delay (clock tree delay). The architecture employs a frequency detector circuit which monitors the frequency of the input clock and then sets a division factor for a reference clock used to control delay tap selection. In this way, the architecture can support a fast locking time, coarse tuning and fine-tuning.

Abstract: A transition detect circuit includes: a first input port referenced to a first supply voltage node and a second input port referenced to a second supply voltage node. The circuit simultaneously monitors both ports for transitions, and once a transition occurs, directly generates the translated control signals at its output. Once a transition occurs at the inputs, the translated control signal is generated at the output within at most two gate delays. The circuit has very low quiescent current.

Abstract: A voltage transfer circuit outputs an equivalent to an input voltage when enabled. Otherwise, the transfer circuit is in standby and outputs an equivalent to a standby voltage (e.g., signal ground). The voltage transfer circuit includes a switching circuit, a standby circuit, and an input-transfer circuit. The output of the transfer circuit is fed back to both the switching circuit and the input-transfer circuit. When the transfer circuit is in standby, the feedback of the output voltage provides for voltage-balancing in the input-transfer circuit, thereby reducing or eliminating leakage current in the input-transfer circuit. Similarly, when the transfer circuit is in active mode, the feedback of the output voltage provides for voltage-balancing in the standby circuit, thereby reducing or eliminating leakage current in the standby circuit.

Abstract: A power-on reset circuit is provided. The power-on reset circuit includes an adjusting circuit, a charging/discharging unit and an output circuit. The adjusting circuit receives and adjusts a clock signal so as to output a control signal, wherein a minimum level of the control signal is clamped to be higher than a pre-defined level. The charging/discharging unit having a capacitor apparatus receives the control signal, determines whether to charge/discharge the capacitor apparatus based on the control signal, and outputs a storage voltage of the capacitor apparatus. The output circuit receives the storage voltage and outputs the reset signal. Wherein, the adjusting circuit determines the charging/discharging duty cycle of the charging/discharging unit by adjusting the waveform and the minimum level of the control signal. The output circuit enables/disables the reset signal according to whether the storage voltage reaches the threshold voltage of the output circuit.

Abstract: A clamping circuit containing a transistor and a current amplifier. The transistor is designed to turn on when the voltage at a node exceeds (falls below) a specified upper (lower) level. The current amplifier is designed to draw substantial amount of current when the transistor is turned on to clamp the voltage at the node to the desired level.

Abstract: A differential charge pump circuit has two current paths and generates a differential current in accordance with currents inputted to the two current paths. The two current paths have a pair of current sources respectively and form a differential pair. The differential charge pump circuit has controlling means for detecting an output potential difference between the two current paths and controlling current values of the current sources in accordance with the output potential difference.

Abstract: A sample-hold circuit, which reduces droop and feed through and is suitable for high-speed operation while maintaining a wider freedom of design parameters, comprising a preamplifier to which an input analog signal is applied, a core section which outputs a voltage corresponding to the variation of an output from the preamplifier during the sampling period and holds the voltage corresponding to the output from the preamplifier during the hold period initiated by a transition of a clock signal, and a current switching circuit which is connected to the output pin of the preamplifier and enables the current flowing into the first transistor within the preamplifier during the sampling period to flow into another second transistor to apply a constant potential as an input to the core section.

Abstract: A short pulse rejection circuit is disclosed. The circuit comprises a signal transition detecting circuit, a control signal generating circuit, a capacitor resetting and charging circuit, and a charge pulse detecting circuit. The signal transition detecting circuit is to output detecting pulses in response to any input pulse. The control signal generating circuit generates two control signals for capacitor charging and discharging in response to the detecting pulses. The capacitor resetting and charging circuit generates discharging and charging signals in response to two control signals. The charge pulse detecting circuit generates output enable pulse and outputting a short pulse rejected pulses in response to the charging signals and original input pulse.

Abstract: This disclosure concerns a semiconductor device that includes a booster portion including first switches and first capacitors; and a voltage converter comprising boosting stages each of which includes a second capacitor whose one end is connected to a first voltage source via a second switch and whose other end is connected to a reference voltage via a third switch, the second capacitor being charged on the basis of a voltage difference between the first voltage source and the reference voltage, and comprising fourth switches each of which is provided between two of the boosting stages to control the number of the second capacitors connected in series between a second power source and the other ends of the first capacitors according to the voltages of the first and second voltage sources, the voltage converter outputting clock signals with phases opposed to each other to adjacent ones of the first capacitors.

Abstract: An interface circuit which outputs a clock signal and data to a data register that serially reads in the data synchronously with the clock signal, in response to a control signal changing from one level to the other level, for outputting the clock signal and the data. The interface circuit comprises a clock output circuit that, responding to the level of the clock signal when the control signal changes from the one level to the other level, outputs clocks of the clock signal that are the same in number as bits of the data to the data register.

Abstract: A track and hold (or sample and hold) offset compensated amplifier circuit that performs offset compensation in response to a comparison of sign (or sign and value) of the current forced to the output terminal of operational amplifier in order to keep it at the potential of holding capacitor during the holding phase. Based on this comparison, the comparison circuit increases or decreases the voltage differential applied between the positive and negative input terminals of the operational amplifier depending on whether the comparison circuit detects that the current forced to the output terminal of the operational amplifier is positive or negative. During the holding phase, negative feedback is disconnected, and the positive and negative input terminals of the operational amplifier are connected.

Abstract: An operation switching circuit switches over two comparators, which receives communication data, in accordance with a normal mode and a standby mode of a microcomputer. A delay circuit delays a mode switching signal. The mode switching signal and the delayed signal are combined by an OR gate and an AND gate to two comparator control signals, which have different high level periods. The comparators are driven by the comparator control signals, while a multiplexer is driven by the delayed signal. When one comparator is switched from the inoperative state to the operative state, the other comparator is continued to be held operative for the delay period before being switched to the inoperative state.

Abstract: A switched operation amplifier including a biased circuit, an amplifier circuit, and a buffer circuit is provided. The biased circuit is to provide a first, a second, and a third biased signals by means of an input signal and a reference current source. The amplifier circuit is driven by the biased signals through current mirrors, a sample-and-hold switch, a complementary sample-and-hold switch and a differential pair. The buffer circuit includes a capacitor and two transistors in series. An output signal is generated from a node in between the two transistors, and fed back to a negative terminal of the differential pair of the amplifier circuit. The amplifier circuit charges the capacitor and controls one of the transistors of the buffer circuit until the voltages of a positive and the negative terminal of the differential pair are equal. By means of the operation of the switched op amplifier, the output voltage can be kept being stable.

Abstract: A clock frequency divider is provided which has first through Pth (where P is an integer) sub-counters, each capable of counting M+1 clock pulses and provided in parallel, and first through Pth clock signals are provided to the sub-counters, which has same period as a reference clock signal and are sequentially shifted by 1/P of the period of the reference clock signal. Of the first through Pth sub-counters, when the Nth sub-counter (where N is an arbitrary number from 1 to P) finishes counting a prescribed number M of reference clock pulses, all the other sub-counters are initialized, or, at least the (N+1)th sub-counter is initialized.

Abstract: A circuit comprising a first switch for sampling a differential signal and a second switch for level-shifting the sampled differential signal is disclosed. The first and second switches are cross-coupled to cancel a charge injected between the first and second switches and for linearizing the charge transfer; and a capacitor coupled is between the first and second switches. A circuit in accordance with the present invention adds an extra sampling switch to the sampling circuit and an extra charge-transfer switch in the level-shifting circuit. By cross-coupling these extra switches, the result is a cancellation of the charge-injection, and thus linearizing the charge transfer.

Abstract: A power-low reset circuit is provided. The power-low reset circuit receives a reset signal outputted from a power on reset circuit and a stored voltage of a capacitive device in the power-on reset circuit provides an electrical path when a power voltage drops under a predetermined voltage level. The power-on reset circuit is used for generating the reset signal at an initial moment of turning on a power source. The capacitive device can be discharged or charged through the electrical path to restore to its initial status.

Abstract: A high-speed gated flip-flop includes a latch configured to generate a data output signal (Q) in response to a data input signal (D) and a pair of true and complementary clock pulses (GCP,GCPB). These clock pulses are provided by a clock generator responsive to a periodic clock signal (CK). A control circuit is also provided. The control circuit is coupled to a feedback node (ND2) in the pulse generator. The control circuit configured to selectively enable the pulse generator in response to an enable signal (/EN). The pulse generator is configured so that an active transition of the true clock pulse (GCP) is fed back to the feedback node (ND2) in a manner that resets the pulse generator and terminates the true and complementary clock pulses in-sync with the active (e.g., low-to-high) transition of the true clock pulse (GCP).