Patent classifications
H03K19/0005
ZQ CALIBRATION USING CURRENT SOURCE
A memory device includes a terminal calibration circuit having at least one of a pull-down circuit or a pull-up circuit used in calibrating an impedance of a data bus termination. The memory device also includes a reference calibration circuit configured to generate a calibration current. The terminal calibration circuit can be configured to program an impedance of the least one of a pull-down circuit or a pull-up circuit based on the calibration current.
SEMICONDUCTOR APPARATUS PERFORMING CALIBRATION OPERATION AND A SEMICONDUCTOR SYSTEM USING THE SAME
A semiconductor apparatus includes a calibration circuit and a main driver. The calibration circuit is configured to generate a first calibration code when set to have a positive offset and generate a second calibration code when set to have a negative offset complementary to the positive offset. The main driver is configured to set a resistance value of the main driver based on the first and second calibration codes.
Programmable termination circuits for programmable devices
Configurable termination circuits for use with programmable logic devices are disclosed. In one implementation, the termination circuit may include one or more components to couple unused inputs of one or more configurable logic blocks to a fixed voltage. In another implementation, the termination circuit may include one or more components to couple unused inputs of one or more configurable logic blocks to an output of the one or more configurable logic blocks. In some implementations, the programmable logic device may include a platform management controller to configure the termination circuits based on configuration data.
On-die termination control
A memory control component outputs a memory write command to a memory IC and also outputs write data to be received via data inputs of the memory IC. Prior to reception of the write data within the memory IC, the memory control component asserts a termination control signal that causes the memory IC to apply to the data inputs a first on-die termination impedance during reception of the write data followed by a second on-die termination impedance after the write data has been received. The memory control component deasserts the termination control signal to cause the memory IC to apply no termination impedance to the data inputs.
I/O BUFFER OFFSET MITIGATION
Memory including an array of memory cells might include an input buffer having calibration circuitry, a first input, a second input, and an output; and calibration logic having an input selectively connected to the output of the input buffer and comprising an output connected to the calibration circuitry, wherein the calibration logic is configured to cause the memory to determine whether the input buffer exhibits offset while a particular voltage level is applied to the first and second inputs of the input buffer, and, in response to determining that the selected input buffer exhibits offset, apply an adjustment to the calibration circuitry while the particular voltage level is applied to the first and second inputs until a logic level of the output of the selected input buffer transitions.
PAM-4 CALIBRATION
A hybrid voltage mode (VM) and current mode (CM) four-level pulse amplitude modulation (PAM-4) transmitter circuits (a.k.a. drivers) is calibrated using a configurable replica circuit and calibration control circuitry. The replica circuit includes an on-chip termination impedance to mimic a receiver's termination impedance. The amount of level enhancement provided by the current mode circuitry is calibrated by adjusting the current provided to the output node and sunk from the output node by the replica current mode circuitry while the replica voltage mode circuitry is driving an intermediate PAM-4 level. After the level enhancement has been set, the non-linearity between levels is calibrated by adjusting the amount of current provided to the output node by the replica current mode circuitry while the replica voltage mode circuitry is driving a maximum output voltage level.
Slew-limited output driver circuit
A slew-limited output driver circuit facilitates finding a circuitry that allows a flexible setting of the slew-rate of an integrated circuit, with only a small footprint and latency, and which allows realizing different driver modes without additional components integrated protection against ESD. A short circuit will be solved by a slew-limited output driver circuit comprising a switchable current mirror providing an output current equal to an input current, wherein the current mirror is controlled by an additional switch, which is switched in response to control signals and/or an output current level of the output driver circuit, wherein adjustable operating modes of the slew-limited output driver circuit are realized by the control signals.
MODULAR ANALOG SIGNAL MULTIPLEXERS FOR DIFFERENTIAL SIGNALS
An example analog signal multiplexer includes two differential input signal ports for receiving a first and a second differential input signals, IN1 and IN2. The multiplexer further includes a differential output signal port with two output terminals OUT+ and OUT, for outputting a signal based on one or more of the input signals IN1 and IN2. Furthermore, the multiplexer includes a pair of load elements, and an additional differential output signal port that has two output terminals TERM+ and TERM. The load elements are not coupled directly to the output terminals OUT+ and OUT, but, rather, are coupled to the output terminals of the additional output signal port, TERM+ and TERM, enabling a modular approach where multiple instances of the multiplexer may be combined on an as-needed basis to realize multiplexing between a larger number of differential inputs that a single multiplexer would allow.
Semiconductor memory device and memory system having the same
The semiconductor memory device including a data strobe signal input buffer configured to receive a data strobe signal and generate an input data strobe signal, a data input buffer configured to receive data delayed by a first delay time compared to the data strobe signal and generate input data, a latency control signal generator configured to generate and activate a first on-die termination control signal during a first period in which the data strobe signal is applied in response to receiving a write command, a first on-die termination control circuit configured to vary a first variable resistance code in response to the first on-die termination control signal, and a data strobe signal termination circuit configured to terminate the data strobe signal and including a first on-die termination resistor, a resistance value of which varies in response to the first variable resistance code may be provided.
Self-adaptive termination impedance circuit
A memory system includes a memory device with a termination circuit providing a termination impedance for a data signal in the memory device. The device also includes a calibration circuit configured to set the termination impedance to a predetermined value. The device further includes an impedance adjustment circuit configured to adjust the termination impedance based on a feedback signal indicating a change in the termination impedance due to at least one of a change in a temperature of the memory device or a change in voltage of a voltage bus in the memory device.