摘要 |
<p>In an embodiment of the invention, a flip-flop circuit (100) contains a 2-input multiplexer (102), a master latch (104), a transfer gate (106) and a slave latch (108). The scan enable control signals SE and SEN of the multiplexer determine whether data or scan data is input to the master latch. The clock signals CLK and CLKN and retention control signals RET and RETN determine when the master latch is latched. The slave latch is configured to receive the output of the master latch, a second data bit D2, the clock signals CLK and CLN, the retain control signals RET and RETN, the slave control signals SS and SSN. The signals CLK, CLKN, RET, RETN, SS and SSN determine whether the output of the master latch or the second data bit D2 is latched in the slave latch. Control signals RET and RETN determine when data is stored in the slave latch during retention mode.</p> |