Apple Inc.

Motorlola, Inc.

Derrick Andrew Leach

Edward Martin McCombs, Jr

Donovan Scott Popps

Frank Arlen Miller

Thomas J Best

Embodiments of a scannable flip-flop are disclosed that may reduce data hold time, which may in turn improve the performance of circuits incorporating the scannable flip-flop. The scannable flip-flop may include a slave latch and a master latch including an input multiplexer. The multiplexer may include a number of input ports, for example to receive normal operating mode data as well as scan operating mode data, and the multiplexer may be operable to controllably select one of the input ports and pass the value of the selected port to an output of the multiplexer. For example, the multiplexer may generate individual control signals for the various ports dependent upon both the clock signal and a select signal, such that each of the ports is qualified with the select signal and the clock signal before the multiplexer presents the input data of the selected port as the output of the multiplexer.

Scannable flip-flop with hold time improvements

A synchronous pipelined burst memory (20) achieves high speed by violating conventional pipelining rules. The memory (20) includes an address register (24) which latches a burst address during a first cycle of a periodic clock signal. The burst address is driven to an input of an asynchronous memory core (40), but output data from the asynchronous memory core (40) is not latched until a third cycle of the periodic clock signal which occurs after a second cycle of the periodic clock signal which is immediately subsequent to the first cycle. The memory (20) outputs successive data elements of the burst during consecutive cycles of the periodic clock signal to complete the burst cycle.

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Austin, TX, United States of America

Derrick Andrew Leach