Abstract:
Frequency detector and oscillator circuits are disclosed. Example frequency detector and oscillator circuits disclosed herein include a current approximation circuit coupled to an external clock operating at a target frequency. In some examples, the current approximation circuit is configured to determine a magnitude of a first current to charge a capacitor to reach a reference voltage during a first set of clock cycles generated by the external clock. In some examples, the current approximation circuit is further configured to generate an output current based on the magnitude of the first current and to use the output current to produce a comparator output. In some examples, the frequency detector and oscillator circuits further include a latching circuit coupled to receive the comparator output from the current approximation circuit. In some such examples, the latching circuit is configured to generate oscillating signals at the target frequency based on the comparator output.
Abstract:
A floating input detection method and circuits. A method for detecting a floating signal input terminal includes providing a common-mode input voltage to a first amplifier coupled to the signal input terminal, and providing an output signal generated by the first amplifier to: a non-inverting input of a second amplifier coupled to the signal input terminal, an inverting input of the second amplifier, coarse detection circuitry, and fine float detection circuitry. The method also includes comparing, by the coarse detection circuitry, the output signal to a first threshold voltage, and determining the signal input terminal to be not floating responsive to the comparing indicating that the output signal is greater than the first threshold voltage.
Abstract:
Frequency detector and oscillator circuits are disclosed. Example frequency detector and oscillator circuits disclosed herein include a current approximation circuit coupled to an external clock operating at a target frequency. In some examples, the current approximation circuit is configured to determine a magnitude of a first current to charge a capacitor to reach a reference voltage during a first set of clock cycles generated by the external clock. In some examples, the current approximation circuit is further configured to generate an output current based on the magnitude of the first current and to use the output current to produce a comparator output. In some examples, the frequency detector and oscillator circuits further include a latching circuit coupled to receive the comparator output from the current approximation circuit. In some such examples, the latching circuit is configured to generate oscillating signals at the target frequency based on the comparator output.
Abstract:
The disclosure provides an analog to digital converter (ADC). The ADC includes a comparator that receives a threshold voltage. A set of elementary capacitors is coupled to the comparator, and receives one of an input voltage and a set of reference voltages. A set of M offset capacitors is coupled to the comparator, and receives one of a primary voltage and a secondary voltage, M is an integer. A difference in the primary voltage and the secondary voltage varies linearly with temperature.
Abstract:
A device includes a SAR, a comparator, a DAC and a multichannel passive S/H component. The multichannel passive S/H component is able to sample and hold a plurality of analog voltages in parallel. The multichannel passive S/H component is further able to serially feed the plurality of sampled and held analog voltages to the SAR, comparator and DAC, such that each analog voltage is serially converted to a digital representation.
Abstract:
A device includes a SAR, a comparator, a DAC and a multichannel passive S/H component. The multichannel passive S/H component is able to sample and hold a plurality of analog voltages in parallel. The multichannel passive S/H component is further able to serially feed the plurality of sampled and held analog voltages to the SAR, comparator and DAC, such that each analog voltage is serially converted to a digital representation.