International Business Machines Corporation

Joseph O Marsh

Michael Won

William D Corti

James Stephen Mason

Jeremy K Stephens

Joseph Natonio

Matthew B Baecher

Charlie Chornglii Hwang

Huihao Xu

Mark R Taylor

Thomas J Bardsley

James M Wilson

Jack Allan Mandelman

Louis Lu-Chen Hsu

Steven John Zier

Steven C Parker

Frank X Scanzano

Robert Kenny, Jr

Digital testing of an analog driver circuit is enabled using a circuit including a control circuit for generating signals, a differential driver circuit for receiving a differential input signal, amplifying the differential input signal and transmitting a differential output signal, a programmable termination impedance circuit for generating a differential termination impedance at the output node of the differential driver circuit, and a differential receiver circuit for converting the differential output signal to a single ended signal and transmitting the single ended signal. The testing includes skewing a differential output termination impedance, adjusting a differential receiver circuit voltage offset, selecting a differential driver circuit power level, enabling a decoder which activates only one differential driver circuit segment per test sequence, activating a segment, stimulating the differential driver circuit with digital test patterns, receiving differential driver circuit output, converting the output to a single-ended signal, and observing the single-ended signal.

System and method of digitally testing an analog driver circuit

A method of testing connectivity through a plurality of dual purpose current mode logic ('CML') latch circuits connected in a series is provided. Each of the CML latch circuits are operable to latch at least one output signal at a timing in accordance with at least one clock signal and having a mode control device for operating the CML latch circuit as a buffer amplifier when the at least one clock signal is inactive. The method comprises the steps of activating the mode control devices of each of the CML latches to operate each of the CML latches as a buffer; inputting a first signal to a first CML latch of the series; latching an output signal of a second CML latch of the series, the second CML latch being connected at a point in the series downstream from the first CML latch; and determining whether the output signal changes in accordance with a change in the first signal.

Method of testing connectivity using dual operational mode CML latch

A circuit of testing an analog driver circuit using digital scan-based test methodologies. The circuit of the present invention includes a control circuit for generating signals in response to a test enable signal, a differential driver circuit for receiving a differential input signal, amplifying the differential input signal and transmitting a differential output signal in response to the differential input signal and the signals generated by the control circuit, a programmable termination impedance circuit for generating a differential termination impedance at the output node of the differential driver circuit in response the signals generated by the control circuit, and a differential receiver circuit for receiving the differential output from the differential driver circuit, convert the differential output signal to a single ended signal and transmitting the single ended signal, all in response to the test enable signal.

System of digitally testing an analog driver circuit

A dual purpose current mode logic ('CML') latch circuit is provided which includes a CML latch operable to receive at least a pair of differential input data signals and at least one clock signal. The CML latch is operable to generate at least one output signal in accordance with the states of the pair of input differential data signals. A mode control device is operable to receive a mode control signal to operate the CML latch as a buffer or as a latch. In such way, when the mode control signal is inactive, the CML latch generates and latches the output signal at a timing determined by the at least one clock signal, and when the mode control signal is active the CML latch generates the output signal such that the output signal changes whenever the states of the pair of differential input data signals change.

Dual operational mode CML latch

In a first aspect, a method of testing an analog circuit is provided. The method includes (1) providing the analog circuit with a screening circuit adapted to cause the analog circuit to function like a logic gate during a test; and (2) applying digital signals to the analog circuit to test the analog circuit at a wafer level so as to detect a defect in one or more components of the analog circuit. Numerous other aspects are provided.

Methods and apparatus for testing an integrated circuit

A method for decoding a memory array address for an embedded DRAM (eDRAM) device is disclosed, the eDRAM device being configured for operation with an SDRAM memory manager. In an exemplary embodiment of the invention, the method includes receiving a set of row address bits from the memory manager at a first time. A set of initial column address bits is then subsequently from the memory manager at a later time. The set of initial column address bits are translated to a set of translated column address bits, and the set of row address bits and the set of translated column address bits are simultaneously used to access a desired memory location in the eDRAM device. The desired memory location in the eDRAM device has a row address corresponding to the value of the set of row address bits and a column address corresponding to the value of the set of translated column address bits.

Method and apparatus for address decoding of embedded DRAM devices

An on-chip logic analysis (OCLA) system captures data processed by a signal processing logic core embedded in a single-chip-device (SOC) without interrupting operations of the signal processing logic core. The OCLA system includes a data capturing unit embedded in the SOC device to monitor the operations of the signal processing unit and determines whether the operations satisfy predetermined trigger conditions. Once the trigger condition is satisfied, the data capturing unit captures internal data from/to the signal processing unit and transfers to an external host system. The host system controls the operations of the data capturing unit. The host system provides the captured data to an user interface for testing and debugging the operations of the SOC signal processing device.

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Poughkeepsie, NY, United States of America

Joseph O Marsh