摘要:
Methods and apparatus are disclosed for using current detection in a test instrument to ensure validity of component test output. In a component test instrument that employs digital synthesis of a test stimulus waveform, voltage scan data and current scan data are successively acquired, the scan data being synchronized relative to the test stimulus waveform. The voltage and current scan data are stored in respective temporary storage buffers. Before displaying the data, a check for an open lead is conducted in a manner similar to a current scan. A zero current value indicates an open lead and the acquired scan data is disqualified from being displayed. Similarly, at the beginning of a component test operation, an open lead test is performed and the first voltage scan is deferred until a validity check confirms that the test leads or probes are in place. The disclosed methods and apparatus ensure that only valid data is displayed to the user.
摘要:
An electronic test instrument adapted for displaying only meaningful information notwithstanding the intermittent arrival of valid input signals due to probing operations is provided. Two independent measurement processes measure the input signal simultaneously. The first measurement process operates in a similar fashion to a digital storage oscilloscope (DSO) by successively sampling the input signal to produce waveform information which are selectively sent to an LCD display device which graphically displays the waveform. The second measurement process continually performs a stability assessment of the input signal by collecting a series of stability measurements of a selected input signal parameter, creating a moving average of the series, and comparing each new stability measurement to the moving average relative to stability criteria. The stability decision controls the flow of waveform information to the display, thereby ensuring that only meaningful information is displayed based on waveform scans conducted when the input signal is stable.
摘要:
A system and method of coordinating power states between two detachable units is disclosed. Only the primary unit has a user-controllable power control. The secondary unit is not directly user controllable. The power states of the two units are coordinated using an actuator mechanism when the units are attached. When the two units are detached, the state of the secondary unit is dependent upon the state of the primary unit and any subsequent commands transmitted by the primary unit to the secondary unit.
摘要:
A system and method of coordinating power states between two detachable units is disclosed. Only the primary unit has a user-controllable power control. The secondary unit is not directly user controllable. The power states of the two units are coordinated using an actuator mechanism when the units are attached. When the two units are detached, the state of the secondary unit is dependent upon the state of the primary unit and any subsequent commands transmitted by the primary unit to the secondary unit.