摘要:
A driving device for a LED module is provided. The driving device for the LED module includes a voltage converting unit, a LED module voltage detecting unit, and a switching signal generation unit. The voltage converting unit produces a driving voltage to drive the LED module according to a switching signal. The LED module voltage detecting unit divides the driving voltage to produce a comparison voltage. The switching signal generation unit receives the comparison voltage by a fault detection pin and compares a reference voltage and the comparison voltage to enable or disable the switching signal. After the switching signal is disabled, the switching signal generation unit further pulls up a voltage level of the fault detection pin to a logic high level voltage, so as to produce a fault notification signal to let the fault detection pin also have a function for fault notification.
摘要:
A flyback voltage converter includes a transformer having a primary winding and a secondary winding, a switch serially connected to the primary winding for being switched to produce a current in the secondary winding, and a negative lock loop to adjust the peak value of the current in the secondary winding according to a current conduction time during which the current in the secondary winding is higher than a current threshold, such that the peak value of the current in the secondary winding will be in inverse proportion to the time.
摘要:
The present invention relates to a cell culture device which includes: a cell culture container comprising a container body and a neck connecting to the container body wherein the container contains a top wall, a bottom wall having a first opening, and at least one side wall to define a cell culture zone, and an end of the neck has a second opening for cells or culture media being injected into the cell culture zone; a biosensor chip having a detective surface which faces the top wall of the cell culture container; and a fastening component for the biosensor chip being fastened in the first opening of the bottom wall. The cell culture of the present invention can be used for real-time detection of the cell growth and further for drug screening.
摘要:
A flyback voltage converter includes a transformer having a primary winding and a secondary winding, a switch serially connected to the primary winding for being switched to produce a current in the secondary winding, and a negative lock loop to adjust the peak value of the current in the secondary winding according to a current conduction time during which the current in the secondary winding is higher than a current threshold, such that the peak value of the current in the secondary winding will be in inverse proportion to the time.
摘要:
A frequency jittering circuit modulates a hysteretic band of an oscillator such that the clock generated by the oscillator has a jitter frequency, and thus a switching mode power supply operative on the clock will have a jittering switching frequency.
摘要:
Time-sharing technique is used for power conversion to improve the thermal dissipation thereof. In a power supply arrangement to provide a supply voltage to a load, a plurality of linear regulators are so switched that each time only one of them is enabled to convert an input voltage to the supply voltage, thereby each of them suffering less thermal dissipation.
摘要:
A flyback converter has a controller to switch a power switch so as to convert an input voltage to an output voltage for a load by monitoring an output voltage dependent signal and a current sensing signal derived from a current flowing through the power switch, a light-load efficiency improving apparatus monitors the load and a supply voltage provided for the controller to selectively clamp the output voltage dependent signal when the load is lower than a first threshold value and the supply voltage is lower than a second threshold value, so as to increase the supply voltage.
摘要:
For protecting a power system, two or three of over current, thermal and under voltage protection circuits are integrated as one protection circuit but operate independently, and one or more protection points thereof are adjusted dynamically in response to detected condition of the power system. Specifically, using voltage and current conditions in the power system to modify the over current protection and the thermal protection maximizes the performance of the power system and covers the process bias in the circuits.
摘要:
The present invention discloses a load-dependent frequency jittering circuit, comprising: a load condition detection circuit for receiving a switching signal and generating an output according to a load condition; a number generator for receiving the output of the load condition detection circuit and generating a number; a digital to analog converter for converting the output of the number generator to an analog signal; and an oscillator for generating a jittered frequency according to the output of the digital to analog converter.
摘要:
The present invention discloses a charge pump start up circuit comprising: a start up transistor having one end which is electrically connected with a voltage supply source, and another end which is electrically connected to a voltage node; and a charge pump circuit having an input which is electrically connected with the voltage node, and an output which is electrically with the gate of the start up transistor.