An undervoltage protection circuit and an overvoltage protection circuit include a first comparator and a second comparator. The first comparator has a first input terminal, a second input terminal, and a first output terminal. The second comparator has a third input terminal, a fourth input terminal, and a second output terminal. The third input terminal receives a reference voltage and the fourth input terminal receives a first feedback voltage. The first and the second output terminals are coupled with a logic device. The first feedback voltage is converted to a second feedback voltage by the delay circuit and the voltage level shifter. The first comparator outputs a detection enabling voltage for undervoltage/overvoltage detection when the first feedback voltage crosses the second feedback voltage. The logic device outputs a protection voltage level undervoltage/overvoltage protection when the first feedback voltage crosses the reference voltage.

Systems and methods for boosting battery voltage with boost converters are provided. Aspects include coupling a discharge path of a battery to an input side of a power converter in a power supply, wherein the power supply comprises a rectifier and the power converter. A charge path of the battery is coupled to an output side of the power converter and a processor monitors an output voltage of the power converter. The processor also monitors an input voltage of the power converter and responsive to the output voltage of the power converter dropping below a threshold voltage, the processor enables the discharge path.

An electronic device having a plurality of external interfaces and capable of supplying a current to external devices connected via the external interfaces, respectively includes power supply control units corresponding to the respective external interfaces and a control unit having respective terminals for outputting a power supply control signal to the power supply control units. The control unit is configured to switch output of the power supply control signal for the power supply control unit corresponding to the selected external interface and control the power supply control signal for the power supply control units corresponding to the selected external interface to be switched off in a case where a state of the common overcurrent detection signal is changed in response to the switching of the output of the power supply control signal.

A switch device includes a switching element that connects/disconnects a current path from a power supply terminal to a ground terminal via a load, and an overcurrent protection circuit that limits output current flowing in the switching element to be an overcurrent limit value or less. When an output short circuit of the load is detected, the overcurrent protection circuit decreases the overcurrent limit value to be lower as a power supply voltage is higher. In addition, the switch device preferably includes a switching element that connects/disconnects a current path from a power supply terminal to a ground terminal via a load, an intermittent control unit that intermittently drives the switching element when an abnormality is detected, and an output voltage monitoring portion that disables the intermittent control unit until an output voltage applied to the load reaches its target value.

[PROBLEM TO BE SOLVED]

It is an object of the present invention to provide an input voltage control device capable of controlling power supply to each load device based on the voltage level of the DC bus.

[SOLUTION]

For example, a first power line L1 (a terminal T1) is inputted with a voltage of 300V to 380V and a second power line L2 (a terminal T1) is inputted with a voltage of 0V. The potential difference between the first power line L1 and the second power line L2, or input voltage Vin, is variable. A constant voltage generator 2 outputs a constant potential (voltage of 24V, for example) to a third power line L3. A reference potential generator 3A outputs a reference potential of 10V, for example. A comparative potential generator 4A outputs a comparative potential which is within the range of 0V to 24V, for example, based on the input voltage Vin. A comparator 5 outputs to an NMOS transistor 6 a conducting potential (voltage of 24V, for example) or an interrupting potential (voltage of 0V, for example) depending on the comparison between the reference potential and the comparative potential. When the comparator 5 outputs the conducting potential, the path between the source and drain of the NMOS transistor 6 is made conductive. When the comparator 5 outputs the interrupting potential, the path between the source and drain of the NMOS transistor 6 is made non-conductive.

The maximum time that external components of a switch mode power supply over-conduct is determined by an actual ambient temperature at which the devices are operating before they are turned on. Their operation time is thus extended when temperatures are low and decreased when temperatures are high.

An electronic system for a surgical instrument is disclosed. The electronic system comprises a main power supply circuit configured to supply electrical power to a primary circuit. A supplementary power supply circuit configured to supply electrical power to a secondary circuit. A short circuit protection circuit coupled between the main power supply circuit and the supplementary power supply circuit. The supplementary power supply circuit is configured to isolate itself from the main power supply circuit when the supplementary power supply circuit detects a short circuit condition at the secondary circuit. The supplementary power supply circuit is configured to rejoin the main power supply circuit and supply power to the secondary circuit, when the short circuit condition is remedied.

An under-voltage lockout (UVLO) circuit configured for indicating that an electronic device may be enabled and disabled based on threshold levels of a power supply voltage. The UVLO circuit has a non-differential comparator configured to have a fixed threshold voltage. A voltage divider having a first terminal connected to the power supply voltage and configured to adapt a compare signal applied to the non-differential comparator to be proportional the power supply voltage such that a desired threshold voltage for the power supply voltage causes the non-differential comparator to change its output state. The UVLO circuit has a hysteresis controller configured for adjusting the compare voltage such that the power supply voltage has at least two threshold voltages to cause the non-differential comparator to change states. The non-differential comparator comprises a flipped gate transistor with a gate-to-source threshold greater than a normally gated transistor.

Example implementations relate to determining a failure event of a power supply. In some examples, an apparatus may comprise logic circuitry coupled to a signal line, the logic circuitry to receive a monitor signal via the signal line, where the monitor signal corresponds to an internal voltage of a power supply that is consumed wholly by the power supply, compare the monitor signal to a reference signal, and determine, based on the comparison, whether a failure event has occurred in the power supply.

An end effector for use with a surgical stapling instrument is disclosed. The end effector comprises a first jaw, a second jaw movable relative to the first jaw to grasp tissue therebetween, and a staple cartridge. The staple cartridge comprises staples deployable into the tissue. The end effector further comprises a magnetic sensor configured to measure a parameter indicative of an identifying characteristic of the staple cartridge, an impedance sensor configured to measure a parameter indicative of an impedance of the tissue, and a processing unit in communication with the impedance sensor. The processing unit is configured to determine a property of the tissue based on an output of the impedance sensor.