Abstract: A configurable architecture, hybrid analog/digital delay locked loop and technique with fast open loop digital locking for integrated circuit dynamic random access memory (DRAM) devices and devices incorporating embedded DRAM. The DLL design and technique disclosed employs a hybrid analog/digital delay line, but does not use conventional closed loop architecture during the digital phase of the locking process.

Abstract: A configurable architecture, hybrid analog/digital delay locked loop and technique with fast open loop digital locking for integrated circuit dynamic random access memory (DRAM) devices and devices incorporating embedded DRAM. The DLL design and technique disclosed employs a hybrid analog/digital delay line, but does not use conventional closed loop architecture during the digital phase of the locking process.

Abstract: A circuit and technique for adjusting and accurately controlling clock duty cycles in integrated circuit devices in which only N-channel current regulating transistors are used in the voltage-controlled inverters and both the rising and falling edges can be adjusted by cascading two such inverters. The potential for cascading of these inverters allows for additional accuracy to be achieved.

Abstract: A DLL circuit uses a rising edge DLL to align the rising edge of the output data to the system clock and a falling edge DLL to align the falling edge of the output data. The DLL circuit does not use the falling edge of the input clock to provide a reference for the falling edge DLL. The DLL circuit uses the rising edge of a first reference clock (a buffered version of the input clock) to align the rising edge of the output data. An additional DLL is used to generate a precise second reference clock that is delayed by exactly one-half period of the first reference clock to align the falling edge of the output data. Any variation in the duty cycle of the input clock or the input clock buffer does not effect the duty cycle of the output data.

Abstract: A DLL circuit uses a rising edge DLL to align the rising edge of the output data to the system clock and a falling edge DLL to align the falling edge of the output data. The DLL circuit does not use the falling edge of the input clock to provide a reference for the falling edge DLL. The DLL circuit uses the rising edge of a first reference clock (a buffered version of the input clock) to align the rising edge of the output data. An additional DLL is used to generate a precise second reference clock that is delayed by exactly one-half period of the first reference clock to align the falling edge of the output data. Any variation in the duty cycle of the input clock or the input clock buffer does not effect the duty cycle of the output data.

Abstract: A circuit and technique for adjusting and accurately controlling clock duty cycles in integrated circuit devices in which only N-channel current regulating transistors are used in the voltage-controlled inverters and both the rising and falling edges can be adjusted by cascading two such inverters. The potential for cascading of these inverters allows for additional accuracy to be achieved.

Abstract: An equalization circuit for a pair of resistive-capacitive data lines includes primary and secondary equalization circuits attached at both ends of the data line pair. A primary equalization circuit at one end of the data line pair receives a primary control signal, and a secondary equalization circuit at the other end of the data line pair receives a secondary control signal, which is different than the primary control signal. The equalization devices in the primary equalization circuit are attached near the read and write amplifiers and operate normally since all the information is available as to whether or not the corresponding data line pair should be equalized. The additional equalization devices in the secondary equalization circuit placed at the other end of the data line pair receive a simpler control signal that lacks the information as to whether or not any particular data line pair is being equalized.

Abstract: A differential amplifier design and bias control technique of particular applicability for low voltage operation in which the threshold voltage of n-channel differential input transistors is controlled using substrate bias in order to allow a wider range of input signal levels. Further disclosed is a technique for controlling the substrate bias of the input transistors of a differential amplifier based on the level of the output of the amplifier in addition to a differential amplifier circuit capable of low voltage operation in which an additional bias current is introduced that enables the output pull-up current to be increased without increasing the pull-down current, as well as circuitry for optimizing the performance of the differential in both DDR-I and DDR-II operational modes.

Abstract: A differential amplifier design and bias control technique of particular applicability for low voltage operation in which the threshold voltage of n-channel differential input transistors is controlled using substrate bias in order to allow a wider range of input signal levels. Further disclosed is a technique for controlling the substrate bias of the input transistors of a differential amplifier based on the level of the output of the amplifier in addition to a differential amplifier circuit capable of low voltage operation in which an additional bias current is introduced that enables the output pull-up current to be increased without increasing the pull-down current.

Abstract: An analog delay locked loop for receiving a reference clock signal and for generating a delayed output clock signal includes a voltage controlled delay line, a fixed delay line, a delay voltage control, a fast/slow latch, a phase detector, as well as reset and clock off circuits. The fast/slow latch generates three signals that are received by the delay voltage control: a “latched slow signal”, a “latched fast signal”, as well as a “latched fast to slow signal”. The phase detector generates “go fast” and “go slow” signals that are received by the fast/slow latch. The analog delay locked loop sets the initial delay of the delay line at or near its minimum value on start-up. The delay is then forced to increase from the minimum value until a locking condition is achieved independent of the phase relationship between the reference and delayed clock signals.

Abstract: A read data latch circuit that provides a level shift between internal and external voltages that does not require added circuitry dedicated to equalizing or level shifting the data latch nodes. Data lines are provided having a higher capacitance than the capacitance of the data latch nodes. The data latch nodes are connected to the data lines through a switch. When the switch is open, an equalization charge is shared between the data lines and the latch nodes. The voltage for providing the equalization charge and data signals internal to the chip is lower than the data output signals provided to external circuitry by the data latch.

Abstract: A read data latch circuit that requires only two phases to execute a data read cycle. The date read lines and data latch lines are precharged and equalized during the data read cycle. A separate phase for equalizing the data latch nodes is eliminated. Rather, the data latch nodes charge share with the previously equalized and precharged data lines. The latch nodes are effectively precharged and equalized, as the capacitance on the data lines is much larger than the capacitance on the data latch nodes.

Abstract: An architecture for a high speed memory circuit having a relatively large number of internal data lines is shown to include global read and write data lines, and power and ground lines extending laterally across the array. The laterally extending lines are preferably within the third layer of metal. Preferably, the only other metal interconnect over the memory arrays is in the first metal layer, which is used to strap the word lines. Sense amp bands extend longitudinally along the borders of each memory cell bank. Local read and write data lines and read and write column select lines extend through the sense amp bands. Power and ground lines also extend through each sense amp band. Preferably, the architecture includes read path circuitry including a local read circuit that selectively isolates the global read data lines from the local read data lines.

Abstract: A dummy cell arrangement is described for sensing the logic state of an accessed memory cell in an MOS memory in which a memory cell capacitor of a given size is associated with each memory cell. In the preferred embodiment, a plurality of dummy cells are included, each of which has a dummy capacitor of substantially the same given size as a memory cell capacitor. When the state of an accessed memory cell is to be sensed, its memory cell capacitor is coupled to a bit line to change the voltage thereon and a selected dummy cell capacitor is coupled to a pair of bit lines so as to effect substantially equal transfers of charge between the dummy capacitor and the bit lines to which it is coupled. The resulting voltage on the memory cell capacitor's bit line is compared to the voltage on one of the dummy capacitor's bit lines so as to determine the logic state of the accessed memory cell.

Abstract: A static RAM (random access memory) is described wherein fully asynchronous active equilibration and precharging of the RAM's bit lines provides improved memory access time and lower active power dissipation. In the preferred embodiment, each change in the memory's row address is sensed for developing a clock pulse of a controlled duration. The clock pulse is received by a group of equilibrating transistors and a group of precharging transistors which are coupled to the memory's bit lines. When the clock pulse occurs, all the abovementioned transistors conduct to effect simultaneous equilibration and pre-charging of the bit lines.