Capital Microelectronics Co., Ltd.

Rifeng Mai

A buffer circuit includes a buffer group including an odd number of cascade buffers, where the buffers may be different from each other; a PMOS transistor and an NMOS transistor; where a source of the PMOS transistor is coupled to a power source, a drain thereof is connected to an output terminal of the buffer group, and a gate thereof is connected to an input terminal of the buffer group; a source of the NMOS transistor is coupled to ground, a drain thereof is connected to the output terminal of the buffer group, and a gate thereof is connected to the input terminal of the buffer group.

Buffer circuit and electronic device using same

An integrated circuit chip includes at least one driver circuit of single-ended structure and the first drive circuit, the first drive circuit and the at least one driver circuit of single-ended structure have the same structure, the first drive circuit includes a plurality of parallel-connected PMOS tubes and a plurality of parallel-connected NMOS tubes, the plurality of parallel-connected PMOS tubes connect the plurality of parallel-connected NMOS tube in series at a first node. After impedance calibration has been conducted, the chip confines a first impedance calibration code and a second impedance calibration code, and controls the at least one driver according to the first impedance calibration code and the second impedance calibration code; the first reference voltage is preferably configured to &#xbe; times of the supply voltage V, and the second reference voltage is preferably configured to &#xbc; times of the supply voltage V.

Integrated circuit chip and its impedance calibration method

An LVDS data recovery method includes adopting three clocks to sample a received signal clock at the same time, wherein the first clock, the second clock and the third clock have the same frequency and different phases; determining whether the first clock is in the rising-falling edges of the received signal clock, in accordance with sampled levels of the received signal clock sampled by the three clocks at the same time; after determining the first clock is in the rising-falling edges of the received signal clock, adjusting phase of the first clock, and sampling the received data signal in accordance with adjusted phase of the first clock. The LVDS data recovery method ensures that the sampling clock edge is aligned with at the center of the data to be sampled. In case of high speed, the accuracy of the data sampling is guaranteed.

LVDS data recovery method and circuit

A power-on reset (POR) circuit includes an RC circuit; a Schmitt trigger, an inverter, and a first PMOS tube. A power supply voltage charges a capacitor through the RC circuit. When a voltage of the capacitor reaches a first threshold, the Schmitt trigger reverses, a first level is output. The POR circuit includes a discharge circuit used to detect a glitch of the power supply voltage, and output a first signal to an input end of the Schmitt trigger when the glitch is detected. The first signal allows the Schmitt trigger to reverse again to output a second level, so as to turn off the first PMOS tube through the inverting amplifier. When the power supply voltage rises along an oblique line again, the Schmitt trigger reverses, and the first level is output, so as to reset the system where the circuit is.

Zero-current POR circuit

Embodiments of the present invention disclose a level up shifter circuit. The level up shifter circuit further includes two field effect transistors connected in series and a control circuit. Sources of the two field effect transistors and a source of a sixth field effect transistor are respectively connected to a drain of a first field effect transistor and a drain of a second field effect transistor of the conversion circuit, and the control circuit is turned on when a first voltage signal and a third voltage signal are zero at the same time and is turned off in other situations. The level up shifter circuit according to the embodiments of the present invention can effectively solve the problem that an output state is unknown.

Three-mode high-speed level up shifter circuit

A crystal oscillator circuit includes: a crystal resonator circuit, generating an oscillation signal; an inverting amplification circuit, whose amplifier input end is coupled to receive the oscillation signal, in which an inverting amplifier outputs an inverting amplified output signal; a bias circuit, having a bias circuit input end and a bias circuit output end, in which the bias circuit output end generates a bias circuit output signal controlled by the bias circuit input end, and the bias circuit output signal is coupled to a second control end of the inverting amplification circuit; and a peak detection circuit, comparing the inverting amplified output signal with a reference signal, regulating a peak detector output signal, and feeding the peak detector output signal into the bias circuit input end.

Crystal oscillator circuit having low power consumption, low jitter and wide operating range

A phase locked loop (PLL) circuit and a method thereof are provided. In an embodiment, the PLL circuit includes: a switched capacitor circuit, in which the switched capacitor circuit generates a modulation waveform, and the modulation waveform is injected into the PLL circuit in a current form, so that a PLL output frequency is modulated. Compared with the spread spectrum phase locked loop (SS-PLL) in the prior art, the SS-PLL in embodiments of the present invention is simple in structure, low in power consumption, low in silicon overhead, and flexible both in spreading factor and modulation frequency.

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Beijing, China

Rifeng Mai