Etron Technology, Inc.

Exrontechnology, Inc.

Shi-Huei Liu

Bor-Doou Rong

Chun Shiah

Ho-Yin Chen

Tah-Kang Joseph Ting

Jeng-Tzong Shih

Ming-Hong Kuo

Sen-Fu Hong

Cheng-Nan Chang

Lien-Sheng Yang

Tzu-Hao Chen

Te-Yi Yu

Wei-Ju Chen

The latency of a PSRAM is set according to its current state when receiving an external command. If the PSRAM is not executing a specific operation or has completed the specific operation while meeting corresponding timing parameters, the PSRAM is configured to execute the external command with a first latency. If the PSRAM is executing the specific operation or has completed the specific operation before meeting corresponding timing parameters, the PSRAM is configured to execute the external command with a second latency larger than the first latency.

Method of operating PSRAM and related memory device

A latch system applied to a plurality of banks of a memory circuit includes a front latch circuit and a plurality of rear latch circuit. The front latch circuit is used for receiving a datum and a front latch enabling signal, and generating and outputting an intermediate signal according to the datum and the front latch enabling signal. Each rear latch circuit of the plurality of rear latch circuits is coupled to an output terminal of the front latch circuit for receiving the intermediate signal, and generating and outputting a rear latch datum to a corresponding bank of the plurality of banks according to the intermediate signal and a corresponding rear latch enabling signal, where only one rear latch enabling signal is enabled at any time.

Latch system applied to a plurality of banks of a memory circuit

A plurality of refresh requests are generated at a predetermined period shorter than the longest time during which a PSRAM is able to retain a data without being refreshed. For two consecutive first and second refresh requests, the second refresh request is ignored if the interval between the first and the second refresh requests is not larger than a predetermined duration. The first refresh request is delayed if the first refresh request conflicts with an external command of the PSRAM.

Method of controlling a refresh operation of PSRAM and related device

A device for increasing chip testing efficiency includes a pattern generator, a reading unit, a logic operation circuit, and a judgment unit. The pattern generator is used for writing a logic voltage to each bank of a memory chip. The reading unit is used for reading logic voltages stored in all memory cells of each bank. The logic operation circuit is used for executing a first logic operation on the logic voltages stored in all memory cells of each bank to generate a plurality of first logic operation results corresponding to each bank, and executing a second logic operation on the plurality of first logic operation results to generate a second logic operation result corresponding to the memory chip. The judgment unit determines whether the memory chip passes the test according to the second logic operation result.

Device for increasing chip testing efficiency and method thereof

Utilize a pattern generator to write a predetermined logic voltage to each memory cell of a memory chip. Read a predetermined logic voltage stored in the memory cell. Compare the predetermined logic voltage stored in the memory cell with the predetermined logic voltage to determine if the memory cell is a good memory cell or not and store a determination result corresponding to the memory cell in a data latch of the memory chip. And determine if the memory chip is a good memory chip or not according to determination results of all memory cells of the memory chip stored in the data latch of the memory chip.

Method of performing a chip burn-in scanning with increased efficiency

Activate one active word line of two active word lines formed between two isolation word lines to a logic-high voltage, and float another active word line of the two active word lines. Then activate a plurality of first memory cells corresponding to the active word line having the logic-high voltage to a logic '1' voltage, and write a logic '0' voltage to a plurality of second memory cells corresponding to the floating active word line. Then write the logic &#x201c;1&#x201d; voltage to a plurality of bit lines. Then, suspend for charge sharing for a third predetermined time. Finally, read a voltage of the floating active word line to check if any leakage path exists between the floating active word line and the active word line having the logic-high voltage.

Memory device capable of operation in a burn in stress mode, method for performing burn in stress on a memory device, and method for detecting leakage current of a memory device

The embodiments of the present invention disclose a memory device having a fast and shared redundancy decision scheme and a memory control method. The memory device includes an address receiver, a command receiver, a command controller, a row address generator, a column address generator and a shared redundancy decision circuit.

Memory device and memory control method

A new method to sample a digital input signal is achieved. The method comprises sampling a digital input processed through a first digital buffer. The sampling is at the rising edge of a system clock. The switching threshold of a second digital buffer is updated. The digital input processed through the second digital buffer is sampled. The sampling is at the falling edge of the system clock. The switching threshold of the first digital buffer is updated. A digital sampling circuit is achieved.

Dynamic input setup/hold time improvement architecture

A test method is described in which a signal from a tester enters a memory chip or memory module into a special test mode. The special test mode allows leakage defects connected to bit lines to be detected using bit line sense amplifiers. A first test command is issued by a tester, after which a word line is activated. The tester issues a second test command, delayed from the first test command, during the special test mode to turn-on the memory bit line sense amplifiers. The delayed second test command allows sufficient time for the leakage from defects at the crossing of the bit lines and the word line to charge capacitance of the bit lines and allow detection by the sense amplifiers.

Time controllable sensing scheme for sense amplifier in memory IC test

A memory device with burn-in capability is achieved. The device comprises, first, an array of memory cells, and, second, a burn-in test block. The burn-in test block comprises a memory address generator, a data pattern generator, and a command pattern generator. The burn-in test block is capable of writing data to the memory cells, of turning ON word lines in the array, and of holding the array in a static mode. A method to perform wafer level burn-in with this device is disclosed.

Wafer level burn-in for memory integrated circuit

A particular SRAM cell power scheme is disclosed. It ensures that overall chip power is reduced, by eliminating power contributed by defective memory array cells. The VSS path to the 6T memory cell is controlled via NMOS transistors. A VSS Enable (VSSEN) circuit is used to decode which block has a defect. Further, the VSSEN signal can be used to selectively disable a defective cell, or block of cells, by cutting the VSS path via turning off the NMOS transistor, in the normal cell region, and the VSSEN signal can be used to selectively enable a redundant cell, or block of cells, by turning on the VSS path via turning on the NMOS transistor, in the redundant cell region.

Growing community of inventors

Hsinchu County, Taiwan

Shi-Huei Liu