A steady-state voltage on an oscillator output can be detected, independent of control signals received from other circuitry, by an oscillator failure detection circuit (OFDC) fabricated within an integrated circuit (IC). The OFDC can, in response to detecting the steady-state voltage, output an oscillator failure signal on a reference fail output. The OFDC can receive, with a first and a second buffer, an oscillator output signal from an oscillator output. Through the use of an electrically interconnected, pull-down device, pull-up network, pull-up device, pull-down network, Schmitt trigger, inverting Schmitt trigger and OR-gate, the OFDC can drive the oscillator failure signal onto an output of the OR-gate electrically connected to a reference fail output (RFO).

A steady-state voltage on an oscillator output can be detected, independent of control signals received from other circuitry, by an oscillator failure detection circuit (OFDC) fabricated within an integrated circuit (IC). The OFDC can, in response to detecting the steady-state voltage, output an oscillator failure signal on a reference fail output. The OFDC can receive, with a first and a second buffer, an oscillator output signal from an oscillator output. Through the use of an electrically interconnected, pull-down device, pull-up network, pull-up device, pull-down network, Schmitt trigger, inverting Schmitt trigger and OR-gate, the OFDC can drive the oscillator failure signal onto an output of the OR-gate electrically connected to a reference fail output (RFO).

A code generator includes an asynchronous counter that includes first to m-th flip-flops configured to asynchronously output first to m-th output signals in response to a first clock signal, the first to m-th output signals corresponding to first to m-th bits (m being an integer of 2 or more) of a code, respectively, and a synchronous counter that includes (m+1)-th to (m+n)-th flip-flops configured to synchronously output (m+1)-th to (m+n)-th output signals in response to the first clock signal, the (m+1)-th to (m+n)-th output signals corresponding to (m+1)-th to (m+n)-th bits (n being an integer of 2 or more) of the code. The asynchronous counter further includes first to m-th delay circuits configured to respectively delay the first to m-th output signals such that the first to m-th bits of the code are output together at the same time when the (m+1)-th to (m+n)-th bits are output.

A code generator includes an asynchronous counter that includes first to m-th flip-flops configured to asynchronously output first to m-th output signals in response to a first clock signal, the first to m-th output signals corresponding to first to m-th bits (m being an integer of 2 or more) of a code, respectively, and a synchronous counter that includes (m+1)-th to (m+n)-th flip-flops configured to synchronously output (m+1)-th to (m+n)-th output signals in response to the first clock signal, the (m+1)-th to (m+n)-th output signals corresponding to (m+1)-th to (m+n)-th bits (n being an integer of 2 or more) of the code. The asynchronous counter further includes first to m-th delay circuits configured to respectively delay the first to m-th output signals such that the first to m-th bits of the code are output together at the same time when the (m+1)-th to (m+n)-th bits are output.

An apparatus includes a plurality of latches and a plurality of logic gates. Each latch may be setable and resettable. The logic gates may be connected to the latches to form a multi-modulus divider that generates an output clock signal by dividing an input clock signal in response to a command signal. Each latch may be commanded into a corresponding initial state while the command signal is in an initialization state. Each latch is generally free to change states while the command signal is in a run state. A modulus division operation of the multi-modulus divider may start upon an initial edge of the input clock signal after the command signal changes from the initialization state to the run state.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed () of the rotor (103) to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit (104) generates a pulsed output signal indicative of the rotational speed () of the rotor and a rotational position () of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed () of the rotor (103) to generate a filtered drive current signal, and to generate a varying threshold based on the filtered drive current signal. Based on a comparison between the filtered drive current signal and the varying threshold, the ripple count circuit (104) generates a pulsed output signal indicative of the rotational speed () of the rotor and a rotational position () of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed () of the rotor (103), and to generate a pulsed output signal indicative of the rotational speed () of the rotor and a rotational position () of the rotor.

A motor control system includes a variable voltage supply in signal communication with a direct current (DC) motor. The DC motor includes a rotor induced to rotate in response to a drive current generated by a variable supply voltage delivered by the voltage supply. The rotation of the rotor (103) generates a mechanical force that drives a component. A ripple count circuit (104) is configured to filter the drive current based on a rotational speed () of the rotor (103), and to generate a pulsed output signal indicative of the rotational speed () of the rotor and a rotational position () of the rotor.

Disclosed is an N-bit counter including: an N-bit counting circuit starting counting from an initial value to generate a count value composed of N bits, and being loaded with the initial value to restart counting from the initial value when a reload signal changes from a first reload level to a second reload level; a reload signal generating circuit having the reload signal change from the first reload level to the second reload level when the logical conjunction of K bit(s) among the N bits changes from a first value to a second value; and a reset circuit having a reset signal change from a first reset level to a second reset level so as to have the reload signal change from the second reload level to the first reload level and thereby allow the N-bit counting circuit to restart counting.