A device for detecting an attachment and detachment of a portable device according to example embodiments of the present disclosure may include a first terminal and a second terminal configured to be connected to the portable device; a pull-up circuit connected to the first terminal; a charging circuit configured to generate an output voltage for charging the portable device; and a controller configured to control the charging circuit to generate the output voltage when a voltage of the first terminal drops in a detachment state, and determine whether to transition to an attachment state based on an output current output through the first terminal during a first period in which the output voltage is generated.

A contact state detection apparatus and a wearable device. The contact state detection apparatus includes: a first electrode and a second electrode, the first electrode and the second electrode being configured to receive an alternating current signal and a first signal to output a differential signal, the differential signal including the first signal and a second signal, the first signal being a detection signal of physiological information of a detected object, and the second signal being a signal formed after the alternating current signal is modulated by the first electrode and the second electrode; and a sampling circuit connected to the first electrode and the second electrode, the sampling circuit being configured to sample the differential signal to obtain a target sampling signal, and the target sampling signal including a first sampling signal corresponding to a first signal and a second sampling signal corresponding to the second signal.

A device for determining impedance at a data pin of a communication interface. In one embodiment, the device includes a current source configured to selectively inject a test current to the data pin. The device also includes a sensing circuit for sensing a first test voltage corresponding to a voltage at the data pin without the test current injected, and a second test voltage corresponding to another voltage at the data pin with the test current injected. The sensing circuit determines the impedance at the data pin based on the first test voltage and the second test voltage.

A battery pack, a method for detecting the battery pack, a charging assembly, and an electric tool are provided for detecting voltage and disconnection of the battery cells. The battery pack may have an output voltage of at least 56V and may include a plurality of series connection units. A voltage detecting module may be utilized for detecting voltage in the battery pack. A battery control module configured to control voltage detecting module may also be employed. The method may involve determining whether the series connection units are disconnected based on rates of voltage change or internal-resistance of the series connection units.

Provided is a handler apparatus that conveys a device under test to a test socket, including: an actuator that, prior to fitting of a device holder to the test socket, fits the device holder, and adjusts a position of the device under test on the device holder; and a conveyer that conveys the device holder in which a position of the device under test has been adjusted, to fit the test socket, where the device holder includes: an inner unit to mount the device under test; an outer unit to retain the inner unit to be movable; and a release button to release a lock of movement of the inner unit, in response to being pressed from a side to which the device under test is mounted, and the actuator sets the inner unit to be movable by pressing the release button and adjusts a position of the inner unit.

An apparatus comprises an output port to be connected to a load; a first input port to receive a first input signal; and a second input port coupled between the first input port and the output port, to receive a second input signal. The apparatus further comprises a coupling circuit to couple the second input signal to the output port and a frequency isolation circuit that has a frequency response to propagate the first input signal to the output port but prevent the second input signal from propagating to the first input port. The apparatus also comprises a detection circuit to determine a voltage of an output signal at the output port, the output signal having a first amplitude range with a load absent at the output port and having a second amplitude range lower than the first amplitude range with the load present at the output port.

A testing apparatus for testing a circuit board is disclosed, which includes an upper plate, a lower plate, and an adaptor circuit board. A plurality of positioning units is received in the lower plate. Each positioning unit has a plurality of length-variable test probes secured therein. Each test probe has a shell and upper and lower probe ends at opposite ends of the shell. In test, the circuit board is put on the lower plate and the upper plate is lowered to push the circuit board and the lower plate toward the adaptor circuit board. The upper ends of the test probes engage with electrical connectors of the circuit board and the lower ends thereof engage with the adaptor circuit board whereby test of the circuit board can be automatically performed by the testing apparatus.

A stress detector for detecting an in-situ stress profile of an electrode has a liquid cell, a holder configured to attach to one end of a sample electrode so that the sample electrode is cantilevered in the liquid cell, a piezo sensor comprising a piezo material in the liquid cell and having a movable end configured to contact the sample electrode and a fixed end fixedly engaged within the liquid cell and a measurement sensor in contact with the piezo sensor.

The invention relates to a method for charging a battery comprising rechargeable cells. According to the invention, to perform the ith charge of the battery, where i≧2, connection of the charging terminals to the charger is detected triggering connection of the cells to their bypass circuit during a pre-emptive bypass time (TP.sub.ji). Next, for each cell, during a second phase (C.sub.ji), the bypass circuit is disconnected from the cell until the voltage of the cell reaches a preset voltage, the pre-emptive bypass time (TP.sub.ji) for the ith charge having been calculated as a function of the total connection time, during at least one preceding charge, of the bypass circuit associated with this cell, until all the cells have reached the preset voltage. At least one length of time allowing the first time (TP.sub.ji) for the ith charge and/or said total connection time to be determined was memorized in a memory of the battery during this at least one preceding charge.

Examples of an electronic device are described. In some examples, the electronic device includes a first shared line of a plurality of first contacts to respectively connect to a plurality of integrated circuits, a plurality of second lines of respective second contacts to respectively connect to the plurality of integrated circuits, and a third shared line of a plurality of third contacts to respectively connect to the plurality of integrated circuits. In some examples, the electronic device includes circuitry to determine whether one of the third contacts is connected to an integrated circuit based on a state of the first shared line and a state of one of the second lines that is associated with the one of the third contacts.