The voltage monitoring circuit according to one embodiment of the present invention comprises: a clamping unit for clamping the voltage of input power supplied from a power source to base voltage, and outputting to an MCU; and a switch unit for cutting off the input power from the power source if an anomaly occurs with the base voltage of the clamping unit.

A circuit system for measuring an electrical voltage. The circuit system includes a voltage divider, an integrating element and an evaluating unit. The voltage divider receives, at an input, a first signal that represents the electrical voltage to be measured, and has a first switching element and a second switching element, and is capable of assuming a first state, in which the first switching element is conductive and the second switching element is non-conductive, and a second state in which the first switching element is non-conductive and the second switching element is conductive, and outputs a second signal at an output that is situated between the first switching element and the second switching element. The integrating element is designed to receive the second signal and to output a third signal. The evaluating unit being set up to accept and to evaluate the third signal in order to determine a value for the electrical voltage.

A current measuring system (10) for a commutated motor (20). The current measuring system comprises a bridge circuit (30) with several branches (30a-c), wherein the branches (30a-c) are in each case connected to commutation blocks of the commutated motor (20), and the branches (30a-c) each have a current measuring circuit (60a-c).

An apparatus and method for diagnosing whether a charging and discharging switching element provided on a charging and discharging path of a battery pack operates normally. A charging and discharging switching unit having a charging and discharging switch and a fuse is installed on a charging and discharging path between a battery cell and a pack terminal. The apparatus includes a first diagnosing path a second diagnosing path, a third diagnosing path, an integrated diagnosing path having a diagnosis switching unit and a diagnosis resistor, a voltage measuring unit, and a control unit configured to turn on and off the diagnosis switching unit and determine whether the charging and discharging switching unit is operating abnormally based on the diagnosis voltage measured by the voltage measuring unit.

A voltage monitoring circuit monitors a magnitude relationship between a monitoring target voltage and a determination voltage and is capable of suppressing the influence of an offset of a reference voltage upon the determination voltage and setting the determination voltage as desired. The voltage monitoring circuit includes: an input terminal, applied with a monitoring target voltage or a divided voltage of the monitoring target voltage; a reference voltage generating circuit, generating a first reference voltage; a linear power circuit, converting the first reference voltage to a second reference voltage; a feedback resistor, generating a divided voltage of the second reference voltage, and negatively feeding back the divided voltage of the second reference voltage to the linear power circuit; and a comparing portion, comparing the second reference voltage with the monitoring target voltage or the divided voltage of the monitoring target voltage applied to the input terminal.

A voltage comparator and an operation method thereof are provided. The voltage comparator includes an amplifying circuit, a reference current source, and a transient current source. A first input terminal and a second input terminal of the amplifying circuit respectively receive a first corresponding voltage corresponding to a target voltage and a reference voltage. The reference current source is coupled to the amplifying circuit to provide a reference current. The transient current source is coupled to the amplifying circuit to selectively provide a transient current. The transient current source detects a transition of a second corresponding voltage corresponding to the target voltage to dynamically adjust the transient current. Therefore, when a rapidly increasing voltage occurs in the target voltage, the transient current source may temporarily increase the current of the amplifying circuit, thereby accelerating the response speed of the amplifying circuit.

In an embodiment, a voltage converter includes: a first transistor coupled between an internal node and a first node receiving a supply voltage; a second transistor coupled between the internal node and a second node receiving a reference voltage; an inductance coupled between the internal node and an output node; a first circuit controlling the first and second transistors; and a second circuit configured to detect, when the first and second transistors are in the off state, when the voltage of the internal node is equal to the voltage of the output node, to condition a switching to the on state of the first transistor.

A test verification circuit is described herein for verifying proper operation of a tested circuit, such as a voltage hazard warning circuit, using an N-channel MOSFET configured for switching ON and OFF the test verification circuit during a power outage, and a voltage source that provides an input voltage to the N-channel MOSFET from a conserved power supply. The N-channel MOSFET provides temporary power from a conserved power supply to the test verification circuit upon activation by a user during a power outage, and the test verification circuit determines whether the tested circuit has been de-energized, remains energized, or there remains inadequate power to complete the test.

A power glitch signal detection circuit, a security chip and an electronic apparatus are disclosed. The power glitch signal detection circuit comprises: a latch and a signal output module, wherein a first input of the latch is connected to a power supply voltage, a first output of the latch is connected to a ground voltage, a second input of the latch is connected to a third output of the latch, a third input of the latch is connected to a second output of the latch, and the second output or the third output is connected to the signal output module. The power glitch signal detection circuit could detect a power glitch on the power supply voltage or the ground voltage, and the power glitch signal detection circuit has the advantages of low power consumption, small area, high speed, high sensitivity and strong portability.

A power detection circuit is provided. The power detection circuit includes a comparator circuit operative to generate an output signal in response to an input signal. The output signal is configured to change from a first value to a second value in response to the input signal attaining a first threshold value. The output signal is configured to change from the second value to the first value in response to the input signal subsequently attaining a second threshold value. A current limiting circuit is connected to the comparator circuit and operative to limit a leakage current of the comparator circuit.