Abstract:
A voltage stabilizing circuit including an input port, an output port, a transistor, a diode, a three-terminal voltage regulating reference source, a first resistor, and a second resistor. The transistor has a collector terminal and an emitter terminal connected to the input port and the output port, respectively. The diode has an anode connected to the input port and a base terminal of the transistor. The three-terminal voltage regulating reference source has an anode connected to ground, a cathode connected to the input port and a cathode of the diode, and a reference terminal The first resistor is connected between the cathode of the diode and the reference terminal of the three-terminal voltage regulating reference source. The second resistor is connected between ground and the reference terminal of the three-terminal voltage regulating reference source.
Abstract:
A driver device includes a circuit board, a number of sockets, a number of driver chips, a control switch, and a signal output element. The sockets are positioned on the circuit board. Each driver chip is received in and electrically connected to a corresponding socket. The control switch includes a number of switches. An input of each switch is electrically connected to a corresponding socket. An output of each switch is electrically connected to the computer motherboard through the signal output element.
Abstract:
An electrical connector assembly includes a male connector and a female connector for connectable to the male connector. The male connector includes a male insulating housing and a number of first terminals assembled on the male insulating housing. An anti-mistake insertion bulge extends from the top surface of the male insulating housing. The female connector includes a female insulating housing and a number of second terminals assembled to the female insulating housing for connecting with the first terminals. An anti-mistake insertion gap is defined in the top surface of the female insulating housing. Two cutouts are defined in two opposite sidewalls bounding the anti-mistake insertion gap to hold the anti-mistake insertion bulge.
Abstract:
An all in one (AIO) computer implemented as a personal computer (PC) or a display includes a high definition multimedia interface, a speaker, and a speaker control circuit. The speaker control circuit includes an earphone interface circuit, a main controller, a signal processing unit, and a signal control circuit. The earphone interface circuit detects whether an earphone is inserted into the AIO computer. When the earphone interface circuit detects the earphone is connected to the AIO computer, if the AIO computer is implemented as the PC, the main controller sends a first muting signal. If the AIO computer is implemented as the display, the main controller sends a second muting signal, and the signal control circuit controls and mutes the speaker according to the first muting signal and the second muting signal.
Abstract:
A socket connector packaging includes a main body and a cover. The main body includes a first sidewall and a pivot positioned on the first sidewall. The cover includes a second sidewall, a coupling portion and a stop portion. The coupling portion and the stop portion are positioned on the second sidewall and opposite to each other. The pivot is placed over the coupling portion, thereby making the cover to be rotatable relative to the main body through the pivot. The stop portion is configured for preventing the cover from further rotating when the pivot contacts with the stop portion.
Abstract:
The lighting delay circuit can keep a light being on for a predetermined time then turn off the light. The circuit comprises a thermistor to sense temperature around the light when the light is on, an electronic switch controlled by the thermistor, and a relay controlled by the electronic switch to turn off the light when the electronic switch is turned on.
Abstract:
An auto-shut off circuit includes a relay, a voltage conversion device, a first diode, a second diode, a third diode, a capacitor, a first transistor, and a second transistor. The relay includes a coil and a switch. The auto-shut off circuit disconnects an electronic device from a power supply when the electronic device is not at a working state.
Abstract:
A printed circuit board includes a power layer, a ground layer, a signal layer, and a backboard. The backboard is arranged below the signal layer opposite to the ground layer. A number of vias are formed from the backboard through the signal layer, and then connected to the ground layer.
Abstract:
A layout method of a differential pair generates the differential pair between a differential signal sender and a differential signal receiver in a printed circuit board (PCB). Differential signal is transmitted via two wires. A plurality of vertical lines are created at a breakout section and a trace section of the differential pair. Junctions of the vertical lines and the two wires are defined as pair of points. A first distance between one pin of the differential signal sender and a corresponding point of each pair of points and a second distance between the other pin of the differential signal sender and the other corresponding point of each pair of points are calculated. If a difference between the first distance and the second distance does not fall within an allowable range, the two wires are adjusted.
Abstract:
A temperature controlling alarm circuit includes a power source including a high level terminal and a low level terminal, the low level terminal being grounded; a thermal diode including an anode and a cathode, the anode connected to the high level terminal; a resistor connected to the thermal diode in series; another resistor parallelly connected in parallel to the thermal diode and the said resistor which connected in series; a pnp-type transistor including a base, an emitter and a collector, the base and the emitter being respectively connected to two terminals of the another resistor; and an alarm connected between the collector of the PNP-type transistor and the low level terminal of the power source.