Resources Contact Us Home
Bist DDR memory interface circuit and method for testing the same

Image Number 4 for United States Patent #8035407.

An apparatus and method for self-testing a DDR memory interface are disclosed. In one aspect, a built-in-self-test (BIST) memory interface circuit includes a signal multiplier for receiving a first clock signal from a tester and outputs a multiplied clock signal. A first multiplexer is used for selecting between a test mode and a normal operating mode and provides an output signal. A delay magnitude generator is coupled to the signal multiplier to receive the multiplied clock signal and provides a second clock signal and a phase control signal. A plurality of digitally controlled delay line blocks are used for each receiving the second clock signal and the phase control signal and outputting a phase shifted data strobe output signal in response to receiving an internal data strobe input signal. A second multiplexer selects one of the internal data strobe input signals and a third multiplexer selects the phase shifted data strobe output signal that corresponds to the selected internal data strobe input signal. A phase detector determines a phase difference between the selected internal data strobe input signal and the selected phase shifted data strobe output signal and outputs a phase difference value.

  Recently Added Patents
Anti-infective derivatives, method for the production thereof, pharmaceutical compositions containing same and uses of said derivatives in treatment
Electrical connector
Systems and methods for detecting and rejecting defective absorbent articles from a converting line
Inter-cell power control in the presence of fractional frequency reuse
Method and apparatus for a cryptographically assisted commercial network system designed to facilitate buyer-driven conditional purchase offers
Inductive signal transfer system for computing devices
Polypeptide microparticles
  Randomly Featured Patents
Laser beam machine
Self-locking, self-aligning stepped pin and spring hinge
Transistor, transistor circuit, electrooptical device and electronic apparatus
Voltage limiting test system and assistant test device
High permittivity silicate gate dielectric
Rotational phase adjusting apparatus having seat for drill-machining
Bowling motif tea pot/kettle
Method of manufacturing a semiconductor device including a slab layer with a periodic air hole structure and a linear defect region
Plasma ignition system with recess porton in the center electrode
Rotary piston compressor with inlet and discharge through the pistons which rotate in the same direction