Apparatus and method for operating source synchronous devices
AssigneeTeradyne, Inc.
InventorsRonald A. Sartschev, Jan Paul Anthonie van der Wagt, Nathan Nary, Grady Borders
Life of this patent
Estimating the term…
Abstract
Circuitry and methods of operating the same to strobe a DQ signal with a gated DQS signal are described. Some aspects are directed to a gating scheme to selectively pass a received strobe signal such as a DQS strobe signal based on a state of a drive enable (DE) signal in a drive circuit in the ATE, such that edges generated by the drive circuit are prevented from mistakenly strobing a received data signal such as a DQ signal.
Claims20
An apparatus (100) for synchronization of data received from a semiconductor device (20) with a strobe signal, the apparatus comprising:
- a first connection point (104) configured to connect to a strobe signal pin (24) of the semiconductor device;
- a second connection point (102) configured to connect to a data pin (22) of the semiconductor device;
- a driver circuit (110) having an output (114) coupled to the first connection point and a drive enable input (112), wherein the driver circuit is configured to drive the output during a drive enable period based on a state of a signal (113) at the drive enable input;
- a receiver circuit having a data input (144) and a strobe input (142), wherein the data input is coupled to the second connection point and the receiver circuit is configured to receive data (23) at the data input (144) based on a state of a signal at the strobe input;
- and
- a gating circuit (120), having an input (124) coupled to the first connection point and an output (126) coupled to the strobe input of the receiver circuit and a control input (122) coupled to the drive enable input, wherein the gating circuit is configured to selectively pass a signal from its input to its output based on a state of a signal at its control input.
A method for source synchronization with a semiconductor device, comprising:
- enabling a driver to drive a strobe line of the semiconductor device during a drive enable period of a drive enable signal;
- receiving a strobe signal from the semiconductor device on the strobe line;
- generating a gated strobe signal from the received strobe signal on the strobe line based on the drive enable signal;
- and
- strobing a receiver to record a received data signal on a data line of the semiconductor device based on the gated strobe signal.
A method for operating an automated testing equipment (ATE) to test a semiconductor device, the ATE comprising a driver circuit having an output coupled to a strobe line of the semiconductor device, a receiver circuit, and a gating circuit having an input coupled to the strobe line, the method comprising:
- enabling the driver circuit to drive the strobe line during a drive enable period of a drive enable signal;
- receiving, at the input of the gating circuit, a strobe signal from the semiconductor device;
- generating, with the gating circuit, a gated strobe signal based on the received strobe signal and the drive enable signal;
- and
- strobing the receiver circuit to record a data signal on a data line of the semiconductor device based on the gated strobe signal.
Dependencies are inferred from the claim text.