Feedback type data output circuit of semiconductor memory device

The circuit latches the output of the unit function block of semiconductor memory device to break the data flow and disables a sense amplifier to transmit the don't care signal to a data transmitting circuit. The circuit comprises a sense amplifier (SA') for amplifying and transmitting the faint signal from the unit cell to an I/O line, a read driver (RD') for reading the output signal of the I/O line sense amplifier (SA'), an output latch block (OLB) for latching the output signal of the read driver (RD'), an output buffer (DOB) for buffering the output signal of the output latch block to transmit to the output terminal (Do), a precharge block (PRB) for synchronizing an input terminal (Nd) of the output buffer to the precharge clock (Cp) to precharge, and a state transition detection block (STD) detecting the state transition of data inputing to the input terminal of the output buffer to generate the feedback control clock.