Abstract: A nested ammeter for measuring the electrical current flowing through a device under test (DUT) can include an input configured to receive an input signal having a frequency within a frequency band and representing the electrical current flowing through the DUT. The nested ammeter can also include an output configured to generate an output voltage representing the electrical current flowing through the DUT. An active shunt can be used as the resistive feedback of the ammeter. A nested active shunt can be used as the resistive feedback element of the active shunt.

Abstract: An electronic test measurement system can include a device under test (DUT) and an electronic test instrument that includes a signal input configured to receive an electrical signal from the DUT, a cooling mechanism, and a processor. The processor can be configured to determine a frequency at which the cooling mechanism should operate, cause the cooling mechanism to operate at the determined frequency, select a filter based on the determined frequency, and apply the filter to the electrical signal to reduce interference with the electrical signal resulting from mechanical vibrations of the cooling mechanism.

Abstract: A test and measurement instrument includes a current measurement device having an input to accept an electrical current for measurement, an output to pass an output current output from the current measurement device, a sense path through which the electrical current is measured, and an active bypass device to pass an amount of current from the input of the current measurement device to the output of the current measurement device without passing through the sense path. The active bypass device may be tuned to allow the current sense device to operate without bypass within a specific range of target current values. Some current measurement devices may include more than one active bypass circuits, each tuned for a different range of input current values.

Abstract: A power supply in a test and measurement device includes a stimulus having an output coupled to an amplifier in which an output signal from the stimulus controls an output level of the amplifier. The stimulus may include a Digital to Analog Converter. A measurement circuit detects the output level of the amplifier. The power supply includes an overpulse generator that can be structured to accept a desired amplifier output level, overdrive the stimulus at a first level for a first time period, and drive the stimulus at a second level for a second time period. The measurement circuit determines when the overpulse generator switches from driving the stimulus at the first level to driving the stimulus at the second level. The time period for driving the stimulus at the second level starts as the actual amplifier output level approaches the desired amplifier output level.

Abstract: An electronic device for running an application can include a display to visually present a user interface corresponding to the application. The electronic device can also include a processor to determine whether the application is an originally-installed application and cause the display to include a visually identifiable feature in the user interface indicating that the application is not an originally-installed application responsive to a determination that the application is not an originally-installed application.

Abstract: A test and measurement device including a source configured to output a source signal, a source output configured to output the source signal to a connected cable, a guard drive circuit electrically coupled to the source and configured to receive the source signal and generated a guard drive signal, the guard drive circuit having a gain less than one, and a guard drive circuit output configured to output the guard drive signal to a connected guard.

Abstract: A mechanism is disclosed for mitigating common mode current in a test and measurement device. A measurement current can be received from a device under test via a measurement lead that couples a transformer in the test and measurement device with the device under test. The test and measurement device can then be calibrated to apply a nulling current to cancel the common mode current from the measurement current. Other embodiments can be described and/or claimed herein.

Abstract: A digital-to-analog converter, including an input to receive a digital signal; a first comparator configured to receive the digital signal and output a first signal based on the digital signal and a first threshold; a second comparator configured to receive the digital signal and output a second signal based on the digital signal and a second threshold, the second threshold different from the first threshold; and an integrator configured to receive the first signal and the second signal and integrate the first signal and the second signal into an analog signal that represents the digital signal.

Abstract: A testing environment includes a first measuring unit connected to a gate of a MOSFET device and a second measuring unit connected to a drain of the MOSFET device. The testing environment is particularly useful for testing gate charge for MOSFET devices. In a first phase, the gate of the device is driven with electrical current while the drain is driven with a constant voltage. As the MOSFET device turns on, the second measuring unit switches from providing the constant voltage to providing a constant current to the drain of the MOSFET, while measuring the drain voltage. The switching of modes is automatic and occurs without user intervention. After the MOSFET device has been driven to VgsMax by the gate current, all of the relevant data is stored, which may be analyzed and presented to a user in a User Interface or presented in other manner.

Abstract: A feedback ammeter, which may be included in a source measure unit or a digital multi-meter, for example, including an operational amplifier having an input and an output and a feedback path electrically coupled between the output and the input of the operational amplifier. The feedback path includes a first non-linear device to allow the measurement of decades of current. The ammeter also includes an amplifier electrically coupled to the input of the operational amplifier and the output of the operational amplifier, a second non-linear device electrically coupled to an output of the amplifier, and a resistor electrically coupled between the second capacitor and the input of the operational amplifier. A constant resistance input impedance is established using the second non-linear device that can adjust the circuit gain.

Abstract: The determination and rendering of scan groups for channels configured to acquire data from test and measurement devices in a data acquisition system is disclosed. Based on the particular scan configuration for the data acquisition system, scan groups may be determined for channels in a scan list based on the channel settings, such as measurement type, for example. The data acquisition system renders a graphical scan summary of the channels in the scan list according to their determined scan groups on a display, allowing a user to quickly review the scan configuration.

Abstract: A method in an electronic device that may include determining, with a processor, a quantity of group markers in a data set, and determining, with the processor and based on the quantity of group markers, a suggested view from a plurality of available views, each view in the plurality of available views diagrammatically depicting at least a portion of the data set. Also, a processor-implemented method of navigating between portions of a data set may include displaying, on a touchscreen display, a diagrammatical depiction of a first portion of the data set; detecting a continuous arc gesture at the touchscreen display; determining a direction of the arc gesture; selecting a second portion of the data set based on the determined direction of the arc gesture; and displaying a diagrammatical depiction of the second portion of the data set.

Abstract: A data acquisition system, including an input configured to receive a signal on a port and a processor. The processor determines, during an initial scan, a first measurement value of the signal on the port, sets at least one alarm value based on the first measurement value, the at least one alarm value being within a predetermined amount of the first measurement value, receives, during a subsequent scan, a second measurement value of the signal on the port, and generates an alert when the second measurement value violates the at least one alarm value.

Abstract: A method for calibrating a test instrument having an initial output voltage level and an open output relay can include programming the test instrument for a certain current level, starting a timer, and stopping the timer (responsive to the test instrument entering compliance) to determine a time interval. The method can also include determining whether the time interval is within a desired range.

Abstract: Disclosed is a test and measurement switch matrix. The test and measurement switch matrix includes a solid state switch to couple a test signal from a Device Under Test (DUT) to a test system. The solid state switch has a dual tee guard arrangement providing low leakage when off. The solid state switch also includes an optically coupled drive, which further improves isolation and reduces undesirable charge injection when changing switch states.

Abstract: A system for testing an integrated-circuit wafer includes a probe card and a dispenser assembly. The probe card includes a circuit board and a probe needle coupled to the circuit board. The dispenser assembly is coupled to the probe card and is configured to deliver a metered amount of dielectric fluid to the tip of the probe needle. Methods are also disclosed.

Abstract: A system for testing an integrated-circuit wafer, the system including a probe card having a probe needle and a probe body enclosing a pressure chamber. The probe body includes a unitary sidewall, a first end cap substantially closing a first end of the probe body, except for an outlet passage in the first end cap, and an inlet passage configured to introduce compressed gas into the pressure chamber. The probe needle is within the pressure chamber and is supported by the probe body. A free end of the probe needle extends through the outlet passage. The ends of the probe needle are separated by a first bend in the probe needle, which has a center of curvature that is located between the probe needle and a longitudinal centerline of the unitary sidewall. Methods of using a probe card are also disclosed.