摘要:
A delay locked loop (DLL) circuit for a synchronous semiconductor memory device which can control a delay time of a feedback loop within the DLL circuit according to the magnitude of an external load, and a method of generating information about a load connected to a data pin of a synchronous semiconductor memory device are provided. The DLL circuit includes a replica output driver delaying an internal clock signal by a first delay time to output a first internal clock signal, the first delay time is a delay time of the internal clock signal which is generated by an output driver when a first load of a first magnitude is connected to an output terminal of the output driver, and a transfer/delay circuit transferring the first delay internal clock signal to a phase detector as a second delay internal clock signal when the first load is connected to the output terminal, and outputting the second delay internal clock signal to the phase detector by delaying the first delay internal clock signal by a second delay time, the second delay time is a delay time of the internal clock signal which is generated by the output driver when a second load of a second magnitude, which is larger than the first magnitude, is connected to the output terminal.
摘要:
A delay locked loop (DLL) circuit for a synchronous semiconductor memory device which can control a delay time of a feedback loop within the DLL circuit according to the magnitude of an external load, and a method of generating information about a load connected to a data pin of a synchronous semiconductor memory device are provided. The DLL circuit includes a replica output driver delaying an internal clock signal by a first delay time to output a first internal clock signal, the first delay time is a delay time of the internal clock signal which is generated by an output driver when a first load of a first magnitude is connected to an output terminal of the output driver, and a transfer/delay circuit transferring the first delay internal clock signal to a phase detector as a second delay internal clock signal when the first load is connected to the output terminal, and outputting the second delay internal clock signal to the phase detector by delaying the first delay internal clock signal by a second delay time, the second delay time is a delay time of the internal clock signal which is generated by the output driver when a second load of a second magnitude, which is larger than the first magnitude, is connected to the output terminal.
摘要:
A memory module includes a command/address (CA) register, memory devices, and a module resistor unit mounted on a circuit board. The centrally disposed CA register drive the memory devices one or more internal CA signal(s) to arrangements of memory devices using multiple CA transmission lines, wherein the multiple internal CA transmission lines are commonly terminated in the module resistor unit.