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
Cooling method and device for cooling a medium-voltage electrical installation in a protective sheath
Correction information calculating device, image processing apparatus, image display system, and image correcting method
Light emitting device
Device for transmitting data between a serial data bus and working modules such as actuator modules and/or I/O modules
Estimating stack distances
Image forming apparatus
Database caching utilizing asynchronous log-based replication
  Randomly Featured Patents
Handle attachment, assist mechanism therefor, and electrical switching apparatus employing the same
Simplified process for producing nanoporous silica
Mutant NURR1 gene in Parkinson's disease
Process for the treatment of phosphate ores with silico-carbonate gangue
Image distortion compensation technique and apparatus
Ink jet recording media and method for their preparation
Electronic timepiece
Piperidine compounds for use as stabilizers for organic materials
Narrow bodied, single- and twin-windowed portable laser scanning head for reading bar code symbols
Additive-storing tank assembly and refrigerator having the same