Abstract: A portable apparatus and method for transport and incubation of a medical sample in a blood culture flask includes a sealable container having a thermally insulated compartment for receiving the blood culture flask and a heater for heating the medical sample to a temperature suitable for pre-culturing of the sample. An agitator is provided for agitating the sample in the blood culture flask.

Abstract: A power converter includes an input coupled to an inductor, a first switch coupled to a first comparator, and a second switch coupled to a second comparator. The power converter also includes a pulse comparison counter coupled to the first comparator and the second comparator and a synchronous rectifier (SR) calculator coupled to the pulse comparison counter. The synchronous rectifier calculator is operable to modify a conduction time of the first switch during a first AC half-cycle and modify a conduction time of the second switch during a second AC half-cycle.

Abstract: An apparatus for controlling a power converter operable to receive a cyclically varying input signal includes a discrete-time, on-time generator coupled to the power converter and configured to regulate an output voltage of the power converter and a controller configured to compare the output voltage of the power converter against a first predetermined range to: obtain a comparison result at a zero-crossing of the cyclically varying input signal and select one of a plurality of operation levels of the discrete-time, on-time generator in response to the comparison result. The plurality of operation levels includes a linear, discrete-time operation level and a nonlinear, discrete-time operation level.

Abstract: A method of detecting zero crossings in an AC input voltage at an input of a power converter, including measuring, at a first time, a first voltage. If the first voltage is positive, the method may include determining that the first time corresponds to a positive half-cycle of the AC input voltage. If the first voltage is equal to approximately zero: a) determining that the first time corresponds to a negative half-cycle of the AC input voltage; b) turning on a high-side switch of the power converter for a first time period; and c) measuring, during the first time period, a second voltage. If the second voltage is less than a first threshold, turning off the high-side switch and repeating b) and c) after a time delay. If the second voltage is less than a second threshold, maintaining the high-side switch in an ON state for a second time period.

Abstract: An apparatus for controlling a power converter operable to receive a cyclically varying input signal includes a discrete-time, on-time generator coupled to the power converter and configured to regulate an output voltage of the power converter and a controller configured to compare the output voltage of the power converter against a first predetermined range to: obtain a comparison result at a zero-crossing of the cyclically varying input signal and select one of a plurality of operation levels of the discrete-time, on-time generator in response to the comparison result. The plurality of operation levels includes a linear, discrete-time operation level and a nonlinear, discrete-time operation level.

Abstract: A clinical sample testing system includes a portable apparatus for transport and incubation of a clinical sample in a culture vessel. The apparatus includes a sealable container having a thermally insulated compartment for receiving the vessel and a heater for heating the clinical sample to a temperature suitable for pre-culturing it. The system further includes a microorganism detection device which receives the vessel and cultures the clinical sample. The device includes a) a test aliquot extraction device for removing a test aliquot from the vessel and/or from a second culture vessel sampled therefrom, and a DNA testing device for separating DNA from the test aliquot and performing nucleic acid tests on the DNA to identify the microorganism and detecting genetic antimicrobial resistance markers therein and/or b) an antimicrobial susceptibility test device for performing an antimicrobial susceptibility test on the cultured clinical sample or portion thereof by monitoring microbial growth.

Abstract: A method of setting a synchronous rectifier on-time value includes determining that a time interval has occurred, receiving a number of triangular current mode (TCM) pulses measured during the time interval, and determining a pulse comparison value equal to a number of switching period pulses during the time interval minus the number of TCM pulses during the time interval. The method also includes increasing the synchronous rectifier on-time if the pulse comparison value is greater than or equal to a threshold and decreasing the synchronous rectifier on-time if the pulse comparison value is less than the threshold.

Abstract: A method of detecting zero crossings in an AC input voltage at an input of a power converter includes measuring, at a first time, a first voltage. If the first voltage is positive: determining that the first time corresponds to a positive half-cycle of the AC input voltage. If the first voltage is equal to zero: a) determining that the first time corresponds to a negative half-cycle of the AC input voltage; b) turning on a high-side switch of the power converter for a first time period; and c) measuring, during the first time period, a second voltage. If the second voltage is less than a first threshold, turning off the high-side switch and repeating b) and c) after a time delay. If the second voltage is less than a second threshold, maintaining the high-side switch in an ON state for a second time period.

Abstract: A controller for controlling a switching power converter having an input for receiving a periodic input signal and an output for providing a substantially constant output voltage to a load includes a monitor device configured to compare a switching time interval or a switching frequency with a predetermined threshold value to obtain a comparison result and a parameter recorder configured to record an entry criteria in response to the comparison result, wherein the entry criteria indicates a transition of the switching power converter from a variable switching frequency state to a constant switching frequency state.

Abstract: An apparatus is for moving a sample holder on a platform from a loading position where the sample holder can be removed from the platform to a locked position where the sample holder is securely held. The sample holder is configured to rest on wheels within a recessed portion on the platform. The apparatus is configured such that: (i) movement of the platform from the loading position to the locked position causes a vertical clamp to lower down on top of the sample holder, and a horizontal clamp to be pressed to an outer periphery of the sample holder; and (ii) movement of the platform from the locked position to the loading position causes the vertical clamp to rise above the sample holder, and the horizontal clamp to be moved away from the outer periphery of the sample holder.

Abstract: A method of setting a synchronous rectifier on-time value includes determining that a time interval has occurred, receiving a number of triangular current mode (TCM) pulses measured during the time interval, and determining a pulse comparison value equal to a number of switching period pulses during the time interval minus the number of TCM pulses during the time interval. The method also includes increasing the synchronous rectifier on-time if the pulse comparison value is greater than or equal to a threshold and decreasing the synchronous rectifier on-time if the pulse comparison value is less than the threshold.

Abstract: A method of detecting zero crossings in an AC input voltage at an input of a power converter includes measuring, at a first time, a first voltage. If the first voltage is positive: determining that the first time corresponds to a positive half-cycle of the AC input voltage. If the first voltage is equal to zero: a) determining that the first time corresponds to a negative half-cycle of the AC input voltage; b) turning on a high-side switch of the power converter for a first time period; and c) measuring, during the first time period, a second voltage. If the second voltage is less than a first threshold, turning off the high-side switch and repeating b) and c) after a time delay. If the second voltage is less than a second threshold, maintaining the high-side switch in an ON state for a second time period.

Abstract: A controller for controlling a switching power converter having an input for receiving a periodic input signal and an output for providing a substantially constant output voltage to a load includes a monitor device configured to compare a switching time interval or a switching frequency with a predetermined threshold value to obtain a comparison result and a parameter recorder configured to record an entry criteria in response to the comparison result, wherein the entry criteria indicates a transition of the switching power converter from a variable switching frequency state to a constant switching frequency state.

Abstract: An apparatus is for moving a sample holder on a platform from a loading position where the sample holder can be removed from the platform to a locked position where the sample holder is securely held. The sample holder is configured to rest on wheels within a recessed portion on the platform. The apparatus is configured such that: (i) movement of the platform from the loading position to the locked position causes a vertical clamp to lower down on top of the sample holder, and a horizontal clamp to be pressed to an outer periphery of the sample holder; and (ii) movement of the platform from the locked position to the loading position causes the vertical clamp to rise above the sample holder, and the horizontal clamp to be moved away from the outer periphery of the sample holder.

Abstract: An apparatus for controlling a power converter operable to receive a cyclically varying input signal includes a discrete-time, on-time generator coupled to the power converter and configured to regulate an output voltage of the power converter and a controller configured to compare the output voltage of the power converter against a first predetermined range to: obtain a comparison result at a zero-crossing of the cyclically varying input signal and select one of a plurality of operation levels of the discrete-time, on-time generator in response to the comparison result. The plurality of operation levels includes a linear, discrete-time operation level and a nonlinear, discrete-time operation level.

Abstract: A class-D amplifier with multiple “nested” levels of feedback. The class-D amplifier surrounds an inner feedback loop, which takes the output of a switching amplifier and corrects for errors generated across the switching amplifier, with additional feedback loops that also take the output of the switching amplifier.

Abstract: A method of setting a synchronous rectifier on-time value includes determining that a time interval has occurred, receiving a number of triangular current mode (TCM) pulses measured during the time interval, and determining a pulse comparison value equal to a number of switching period pulses during the time interval minus the number of TCM pulses during the time interval. The method also includes increasing the synchronous rectifier on-time if the pulse comparison value is greater than or equal to a threshold and decreasing the synchronous rectifier on-time if the pulse comparison value is less than the threshold.