3 results about "Rise time" patented technology

A magnetic field generator includes a power source and a segmented or un-segmented coil connected to the power source to generate a time-varying magnetic field. Energy is applied to the coil so that the coil generates a time-varying magnetic field gradient with a magnitude of at least 1 milliTesla per meter and a rise-time of less than 10 microseconds. The coil may be comprised of overlapping, non-overlapping or partially overlapping coil segments that may individually energized to further improve the operating characteristics of the coil to further decrease bio-effects in magnetic resonance imaging through the use of reduced pulse lengths and multi-phasic magnetic gradient pulses.

The invention discloses engineering machinery and an engine temperature control system of the engineering machinery. The engine temperature control system comprises a temperature sensor and a controller. The controller receives temperature information sent by the temperature sensor, the temperature information is compared with a preset temperature value, and control information is generated and sent according to a comparison result; the engine temperature control system further comprises a first blind window, a first drive device, a first transmission device, and/or comprises a second blind window, a second drive device and a second transmission device. The first blind window is arranged on an air inlet of a radiator, the first drive device receives the control information and runs according to the control information, and the first blind window is pushed to be opened and closed through the first transmission device. The second blind window is arranged on a top cover and/or a covering part of an engine, the second drive device receives the control information and runs according to the control information, and the second blind window is pushed to be opened and closed through the second transmission device. According to the engine temperature control system, when the engine is started to operate, rising time of water temperature can be shortened, and/or it is avoided that because the environmental temperature is too high, the water temperature is too high, and then the 'boiling' phenomenon occurs.

The invention provides an explodent elimination circuit. The explodent elimination circuit is used for explodent elimination during power on and power off of an output node of an audio digital-to-analog converter, and comprises four resistors, three positive channel metal oxide semiconductor (PMOS) transistors, two negative channel metal oxide semiconductor (NMOS) transistors, a comparator, a pull-up current source, a pull-down current source and a control logic module, wherein the pull-up current source and the pull-down current source slowly charge the output node or provide a discharge path and can effectively eliminate the explodent of the output node during power on and power off; and the adjustable voltage rise speed and voltage drop speed of the output node are ensured by a current source structure and feedback control. The invention has the characteristics that: the explodent elimination circuit can be widely applied to a power amplifier at the rear end of a single-bit audio digital-to-analog converter, a multi-bit audio digital-to-analog converter or the audio digital-to-analog converter, and can effectively eliminate the explodent caused by abrupt power on or power off of the output node of the audio digital-to-analog converter; the voltage rise time and the voltage drop time of the output node are controllable, complicated control logics are unnecessary, and the power consumption is low.