A signal generator includes a first voltage generator, a second voltage generator, an operational amplifier, and an oscillator. The first voltage generator generates a first voltage, and the second voltage generator generates a second voltage. The operational amplifier generates an amplified error signal based on the first voltage and the second voltage, and the oscillator generates a periodic signal based on the amplified error signal. The first voltage generator and the second voltage generator are configured to generate their respective voltages based on the periodic signal. As a result, frequency deviation in the periodic signal may be corrected, for example, without increasing the source current of the oscillator or the gain of the operational amplifier. Also, improved phase noise performance may also be achieved through an increase in loop gain.

In described examples, an electronic circuit for determining a phase difference between a first clock signal and a second clock signal includes a timer circuit, circuitry for generating a selectively delayed transition of the second clock signal, and phase determination circuitry. The timer circuit produces an elapsed time between a transition of the first clock signal and the selectively delayed transition of the second clock signal. The circuitry for generating the selectively delayed transition of the second clock signal generates the selectively delayed transition in response to a random selection of a respective output from a plurality of second clock signal delay stages. The phase determination circuitry provides the phase difference in response to the elapsed time and the random selection of a respective output from a plurality of second clock signal delay stages.

Embodiments of an integrated circuit (IC) comprising circuitry to determine settings for an injection-locked oscillator (ILO) are described. In some embodiments, an injection signal is generated based on a first clock edge of a reference clock signal, and is injected into an ILO. Next, one or more output signals of the ILO are sampled based on a second clock edge of the reference clock signal, and settings for the ILO are determined based on the samples. In some embodiments, a sequence of two or more time-to-digital (TDC) codes is generated based on a reference clock signal and a free-running ILO. In some embodiments, the TDC circuitry that is already present in a delay-locked loop is reused for determining the sequence of two or more TDC codes. The ILO settings can then be determined based on the sequence of two or more

Some embodiments include apparatuses and methods of fabricating the apparatuses. One of the apparatuses includes a substrate of a semiconductor die; a memory cell portion located over a first portion of the substrate; a conductive pad portion located over a second portion of the substrate and outside the memory cell portion; and a sensor circuit including a portion located over the second portion of the substrate and under the conductive pad portion. The conductive pad portion includes conductive pads. Each of the conductive pads is part of a respective electrical path coupled to a conductive contact of a base outside the substrate.

An integrated circuit that includes a generating circuit is described. During operation, the generating circuit may provide an edge clock having a target phase within a clock period of an input clock, where the generating circuit does not include a delay-locked loop (DLL). For example, the generating circuit may include a gated ring oscillator that provides a reference clock having a first fundamental frequency that is larger than a second fundamental frequency of the input clock. Note that the gated ring oscillator may be programmable to adjust the first fundamental frequency within a predefined range of values. Moreover, the generating circuit may include a control circuit that determines a reference count of a number of edges of the reference clock within a reference period of the reference clock.

The signal generator includes the following: an oscillation generation circuit, configured to generate an initial oscillation signal based on an oscillation control signal; a duty cycle correction circuit, connected to an output end of the oscillation generation circuit and configured to adjust a duty cycle of the initial oscillation signal based on a duty cycle control signal, to generate an adjusted oscillation signal; an output interface, connected to an output end of the duty cycle correction circuit and configured to output the adjusted oscillation signal to an external test system; and an amplitude adjustment circuit, connected to the output end of the duty cycle correction circuit and configured to adjust an amplitude of the adjusted oscillation signal based on an amplitude control signal, to generate a test signal.

A random number generator including: a first ring oscillator including a first inverter chain, the first inverter chain including a plurality of serially connected first inverters, the first ring oscillator configured to output a first random signal generated at a first sub-node between two neighboring first inverters among the plurality of first inverters; a second ring oscillator including a second inverter chain, the second inverter chain including a plurality of serially connected second inverters, the second ring oscillator configured to output a second random signal generated at a second sub-node between two neighboring second inverters among the plurality of second inverters; and a signal processing circuit for generating a random number by combining the first random signal with the second random signal.

An apparatus comprises a first circuit, a second circuit, a first transistor, a second transistor, a third transistor, a first programmable resistance, and a second programmable resistance. The first circuit may be configured to generate a reference signal and a bias signal in response to a supply voltage and a first input signal. The first circuit generally provides supply noise rejection to variations in the supply voltage. The second circuit may be connected to the first circuit and a ring oscillator. The first transistor may be connected to the first circuit and configured to set a first reference current of the first circuit based on the first input signal and the first programmable resistance. The second transistor may be connected in parallel with the first transistor. The second transistor is generally diode-connected. The third transistor may be connected to the first circuit and configured to set a second reference current of the first circuit based on the first input signal and the second programmable resistance. The first circuit generally forms a current mirror with the second circuit. The second circuit may be configured to provide a programmable current ratio for the current mirror based on a value of a second input signal.

An aspect relates to an apparatus, including: a ring oscillator coupled between a first node and a first voltage rail; a control circuit coupled to the first node; a delay line coupled between a second node and the first voltage rail; and a voltage regulator including an input coupled to the first node and an output coupled to the second node.

A signal detection system and a memory detection method are provided. The system includes a signal generator, generating a reference test signal based on an external parameter, the reference test signal being a clock signal satisfying a preset duty cycle, where a duty cycle test is performed on the reference test signal based on a test circuit, to determine whether a function of the test circuit is normal. If the function of the test circuit is normal, different portions under test are sequentially selected based on a test control signal, and the duty cycle test is performed, based on the test circuit, on a signal outputted by each of the selected portions under test. The portions under test include a signal converter and a write clock path.