Sandisk Technologies Inc.

Western Digital Technologies, Inc.

Tianyu Tang

Venkatesh Ramachandra

Srinivas Rajendra

Siddhesh Darne

Ravindra Arjun Madpur

Anil Pai

Amandeep Kaur

Jiwang Lee

Primit Modi

Venkata Kolagatla

Ragul Kumar Krishnan

The present disclosure relates generally to a method of detecting errors in programming data. The method includes receiving a frame of encoded data, and performing a pre-calculation operation on the encoded data. The pre-calculation operation includes passing the frame of encoded data through an error detection circuit comprising eight error flag implementation circuits comprising a plurality of two-input XOR logic gates configured to perform a mathematical equation to return a single output value and an eight input OR logic gate coupled to each output of each error flag implementation circuit. The eight input OR logic gate is configured to return an error flag if one or more output values return a value of 1.

NAND fast cyclic redundancy check

Systems and methods disclosed herein provide for fast write training that be performed to identify an optimal reference voltage for distinguishing between logic levels of an input signal. An example of the systems and methods disclosed herein include receiving a clock signal at an input-output pad of a receiving device and detecting a voltage level of the clock signal based on a duty cycle and voltage swing of the clock signal. A voltage generator circuit is trained to generate a calibrated reference voltage according to the detected voltage level, and the calibrated reference voltage is supplied to an input receiver of the receiving device from the voltage generator circuit.

Fast reference voltage training for I/O interface

The disclosure provides circuits and methods for increasing NAND input/output (I/O) bandwidth during read/write operations. The method includes transmitting a clock signal between a controller I/O circuit and a memory I/O circuit along a read enable bus, transmitting 8 bits of data along an I/O bus, and transmitting 2 bits of data along a data strobe signal (DQS) bus. Transmitting 2 bits of data along the DQS bus includes transmitting a first DQS data signal along the DQS bus and transmitting a first inverse DQS data signal along the DQS bus.

NAND IO bandwidth increase

Systems and methods disclosed herein provide for reduced power composition during data read operations from memory devices through gating of clock signals based on a bit pattern of data to be read from the memory device. Example devices and methods disclosed herein comprise receiving a command to read data from a memory structure of the memory device and latching a bit pattern of the data from the memory structure to a data register based on the received command. The disclose systems and methods use the bit pattern to generate a clock mask according to similarities between bit values within the bit pattern. When a read enable signal is detected on a read enable interface of the embodiments disclosed herein, the clock mask is gated based on the clock mask, and bit values are latched to an input/output interface of the memory device in accordance with the gated read enable signal.

Dynamic clock mask based on read data for power saving

A command/address sequence associated with a read/write operation for a memory device utilizes various existing command/address clock signals in a novel way that obviates the need to utilize the I/O bus. As such, the command/address sequence can be performed in parallel with the DIN/DOUT operations, thereby removing the performance bottleneck that would otherwise be caused by the command and address sequencing. The command/address sequence encodes bit information on first and second enable signals and utilizes rising or falling edges of a clock signal to latch the encoded bit information, which can then be decoded to determine corresponding command and address codes. A chip select sequence is also disclosed that enables a memory chip configuration to be employed in which each chip in a package shares a common connection to a controller but does not require hard-coded pins for performing chip select.

Chip select, command, and address encoding

The present disclosure provides for calibrating clock signals in an unmatched data input system. In various embodiments, an unmatched data input system uses multi-delay circuits to calibrate a clock signal distributed to various input/outputs in the unmatched data input system. These multi-delay circuits can include coarse delay circuits and fine delay circuits that provide a broad range as well as accurate delay capabilities. Through the use of these multi-delay circuits, the unmatched data input system can optimally align a clock signal with its associated data signal across multiple input/outputs.

Receiver side setup and hold calibration

Technology is disclosed herein for a semiconductor die, and controlling operation of the semiconductor die. In some aspects, a semiconductor die is configured to test an I/O circuit on the semiconductor die. The semiconductor die has an input circuit that compares a voltage signal at one of a first input or a second input with a reference voltage at the other of the first input or the second input to generate an input voltage signal. The first input may be connected to an I/O contact. During a normal mode a control circuit on the die provides a reference voltage to second input. During a test mode, the control circuit internally loops back a test signal from an output circuit to the second input of the input circuit. Thus, the test signal avoids the I/O contact.

Input/output circuit internal loopback

Circuits and systems for generating counter signals are provided herein. A circuit may comprise a shift register having a series of flip-flops. Each of the flip-flops of the series may be coupled to a clock. The shift register may generate a borrowing clock signal using an output of a flip-flop of the shift register, and a transition of the borrowing clock signal may be advanced by a number of clock cycles based on a position of the flip-flop of the shift register. The circuit may further comprise a clock divider circuit having a number of divide-by-N counters and a number of flip-flops. A divide-by-N counter may be coupled to a flip-flop of the shift register, and a flip-flop of the clock divider circuit may be coupled to one of the divide-by-N counters and to the clock.

Cycle borrowing counter

Technology is disclosed herein for correcting skew between data signals and a clock signal. In one aspect, a memory system has a delay circuit having delay blocks, with each delay block having one or more inverters. The delay circuit is configured to pass a data signal through either an odd number of the inverters or an even number of the inverters to produce a delayed data signal. The memory system has a skew correction circuit configured to control the number of inverters in the delay circuit through which the data signal is passed in order to correct skew between the data signal and the clock signal. The memory system has a polarity correction circuit configured to invert the data signal in the event that the delay circuit passed the data signal through the odd number of the inverters.

Inverter based delay chain for calibrating data signal to a clock

A correction system is configured to correct for duty cycle distortion and/or cross-point distortion in a pair of sample signals. A slope adjustment circuit is configured to generate a plurality of pairs of intermediate signals according to a plurality of drive strengths. A measurement circuit is configured to measure for duty cycle distortion and/or cross-point distortion, and the slope adjustment circuit is configured to set the plurality of drive strengths based on the measurement. The setting of the drive strengths may reduce certain rising and falling slopes of certain transitions of the plurality of intermediate signals, which in turn may reduce duty cycle distortion and/or cross-point distortion in the sample signals.

Duty cycle and vox correction for complementary signals

Apparatuses, systems, methods, and computer program products are disclosed for accessing non-volatile memory. An apparatus includes one or more memory die. A memory die includes an array of non-volatile memory cells, a set of ports, and an on-die controller. The set of ports includes a first port and a second port. The first port includes a first plurality of electrical contacts and the second port includes a second plurality of electrical contacts. The on-die controller communicates via the set of ports to receive command and address information and to transfer data for a data operation on the array of non-volatile memory cells. The on-die controller uses the first port and the second port in a first mode and uses the first port without the second port in a second mode. The second mode provides compatibility with an interface of a legacy type of memory die.

Interface for non-volatile memory

A skew correction system includes delay circuits positioned in front of sampling circuitry. A skew correction controller first delays an input clock signal to create hold violations. Then with, with the delay of an input clock signal fixed at a reference delay amount, the skew correction controller delays input data signals first to remove or reduce the hold violations, and then to create setup violations. Based on the delaying, the skew correction controller identifies data valid windows for the input data signals, and in turn, identifies target delay amounts that position a delayed clock signal in target sampling positions.

Receiver-side setup and hold time calibration for source synchronous systems

A duty cycle correction system corrects for duty cycle distortion by measuring average time interval durations of consecutive intervals of an input signal. The system generates complementary ramp signals that have cross-points indicating midpoints of the intervals, and detects those cross-points. An output circuit of the duty cycle correction system generates an output signal that performs rising and falling transitions in response to the detected cross-points.

Duty cycle correction on an interval-by-interval basis

A complementary signal path may include an amplifier circuit configured to receive a pair of complementary input signals and a data alignment circuit configured to output a pair of complementary output signals in response to the pair of complementary input signals. A control circuit may detect duty cycle distortion in the pair of complementary output signals and perform a duty cycle correction process to remove the distortion. To do so, the control circuit may search for target current amounts in response to the duty cycle distortion and inject a control current into the amplifier circuit at the target current amounts.

Duty cycle correction scheme for complementary signals

Systems and methods for generating periodic signals with reduced duty cycle variation are described. In some cases, a calibration procedure may be performed prior to a memory operation (e.g., prior to a read operation or a programming operation) in which a duty cycle correction circuit receives an input signal (e.g., an input clock signal), steps through various delay settings to determine a first delay setting corresponding with a signal high time for the input signal and a second delay setting corresponding with a signal low time for the input signal, generates a delayed version of the input signal corresponding with a mid-point delay setting between the first delay setting and the second delay setting, and generates a corrected signal using the delayed version of the input signal and the input signal.

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Milpitas, CA, United States of America

Tianyu Tang