Abstract: Mixed-signal tester architecture and methods are provided which minimize transfer of data, offer parallel data post-processing within the analog channels, and allow flexible synchronization. Multiple analog channels each have a source digital signal processor (DSP), a digital source sequencer, digital source instrumentation, analog source instrumentation, analog measure instrumentation, digital measure instrumentation, a digital pin multiplexer, a digital measure sequencer, DSP-addressable multi-bank capture memory, a capture digital signal processor, and an inter-DSP feedback path for communication between the source DSP and the capture DSP. Each analog channel can be arranged in a feedback loop through either its analog and/or digital instrumentation using the inter-DSP feedback path. DUT response is processed in the channel, the result is used to define parameters for a subsequent test cycle, and a signal corresponding to these parameters is generated and applied to the DUT.

Abstract: Asynchronously-generated digital and analog clocks in a mixed-signal test system are accurately aligned for repeatable and deterministic testing. A variable-frequency digital master clock signal is used in direct digital synthesis of an analog clock signal which is asynchronous to the master clock signal. A resync command inhibits the analog clock signal until the analog clock signal is in a desired phase relationship to the master clock signal. The analog clock signal is thus phase-aligned with the master clock signal in a known and deterministic relationship. The resync command also aligns the phase of the analog clock signal with the pattern of stimulus signals applied to the device under test. Aligning the analog clock signal with the master clock signal and with the stimulus pattern assures that test results are consistent from test-to-test. A phase-locked loop removes spurs from the synthesized analog clock signal.

Abstract: Mixed-signal tester architecture and methods are provided which minimize transfer of data, offer parallel data post-processing within the analog channels, and allow flexible synchronization. Multiple analog channels each have a source digital signal processor (DSP), a digital source sequencer, digital source instrumentation, analog source instrumentation, analog measure instrumentation, digital measure instrumentation, a digital pin multiplexer, a digital measure sequencer, DSP-addressable multi-bank capture memory, a capture digital signal processor, and an inter-DSP feedback path for communication between the source DSP and the capture DSP. Each analog channel can be arranged in a feedback loop through either its analog and/or digital instrumentation using the inter-DSP feedback path. DUT response is processed in the channel, the result is used to define parameters for a subsequent test cycle, and a signal corresponding to these parameters is generated and applied to the DUT.