摘要:
An output buffer circuit is disclosed that has optimized ground bounce characteristics while maintaining low propagation delay. The output buffer may be incorporated within an integrated circuit and may be embodied in either inverting or non-inverting and in either enabling and non-enabling configurations. The output buffer circuit includes a feedback means coupled to the output terminal of the output buffer and to a pull-down transistor. The feedback means provides a feedback voltage to the gate of the pull-down transistor to regulate the derivative of source current with respect to time. The feedback means includes a pair of field effect transistors and either an inverter gate or a NOR gate coupled across one of the feedback field effect transistors.
摘要:
A method and apparatus for performing analog to digital conversion. A voltage to current converter converts an analog input voltage to an input current. A current reference generates a reference current. A plurality of scaling elements scaled the reference current to yield a plurality of scaled reference currents each corresponding to some voltage level within the dynamic range of the input voltage. The input current is compared to each of the scaled reference currents in a plurality of current comparators to generate a thermometer code from which a digital representation of the analog input voltage is derived.
摘要:
A method and apparatus for performing analog to digital conversion. A voltage to current converter converts an analog input voltage to an input current. A current reference generates a reference current. A plurality of scaling elements scaled the reference current to yield a plurality of scaled reference currents each corresponding to some voltage level within the dynamic range of the input voltage. The input current is compared to each of the scaled reference currents in a plurality of current comparators to generate a thermometer code from which a digital representation of the analog input voltage is derived.
摘要:
A high speed current sense amplifier useful in memory devices, which includes a current-to-voltage amplifier that is coupled to a voltage amplifier. The current-to-voltage amplifier has an input impedance that is lower than its output impedance. The voltage amplifier has an input impedance that is larger than the input impedance of the current-to-voltage amplifier. The current sense amplifier can sense the current relationship between two current inputs in about 200 pico-seconds. Embodiments of the current sense amplifier enable current sensing either near the power supply voltage or near ground, thus eliminating the need for intermediate voltages. Embodiments of the current sense amplifier draw current from the current inputs only during the 200 pico-second sensing time and does not require external latching circuitry.
摘要:
The invention relates to a clock signal frequency multiplier circuit. The circuit multiplies the speed of a clock signal of an integrated circuit (IC) by a factor N to generate a times-N clock signal. The circuit first receives a clock signal. Next, the circuit replicates the clock signal into a plurality of N component signals. Each Jth component signal is delayed from the (J-1)th component signal by 1/N cycles, where J equals 1 to N. The (J=1)th component signal is the clock signal. The N component signals are referred to as phase-shifted components. Finally, the circuit logically combines the phase-shifted components into a times-N clock signal.
摘要:
For enabling a static, random-access-memory (500) bit lines (556 and 558) pre-charging circuit (518), employed is an address-change-detection circuit (510) having a plurality of address-change-detectors (570 and 572) each for detecting a change in an associated SRAM addressing signal and, driven by the address-change detectors (570 and 572), a pulse generator (700) driving the pre-charging circuit (518).
摘要:
In one embodiment, the present invention includes an apparatus having a threshold detector with a current comparator to determine if an input signal exceeds a threshold. The input signal may be obtained from a received optical signal and may be compared to a reference signal obtained from a hierarchical Schmitt trigger, in certain embodiments.
摘要:
A frequency prescaler includes an asynchronous counter having a least significant stage clocked by an input signal, and a first true single phase clock flip-flop having an input stage with an embedded logic gate to decode a state of the asynchronous counter, configured to modify a modulus of the asynchronous counter.
摘要:
A content addressable memory has a plurality of entry locations. Each entry location includes a comparison field and an action field. Comparitors are provided for each entry location, so that an input provided to the memory is compared simultaneously to the comparison fields of every entry. The action fields of all entries which match the input value are combined to generate a single output value. Each entry includes a bit which indicates whether such entry is to be deleted when a match occurs with an input value. Each entry in the memory can be assigned an arbitrary label for use in direct accessing by a central processor unit.