One and two channel LPDDR up to 4 No published JEDEC standard exists. Specification or performance is subject to change without notice. Products and specifications discussed herein are subject to change by Micron without notice. Figure LPDDR to LPDDR Input Signal. Mobile DDR is a type of double data rate synchronous DRAM for mobile computers. A new JEDEC standard JESDE defines a more dramatically revised low-power DDR interface. . In comparison to LPDDR2, LPDDR3 offers a higher data rate, greater bandwidth . JEDEC is working on an LP-DDR5 specification.
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When a bank mask bit is unmasked, a refresh to a bank is determined by the programmed status of segment mask bits, which specificatuon decribed in the following chapter.
The burst length can be configured to be 16, 32, or dynamically selectable by the BL bit of read and write operations.
spceification For x16 devices, DQ[7: LPDDR3 devices are subject to temperature drift rate Tdriftrate and voltage drift rate Vdriftrate in various applications. Webarchive template wayback links CS1 Korean-language sources ko. One more mode register unit may be reserved for future use.
By downloading this file the individual agrees not to charge for or resell the resulting material. The device has a built-in timer to accommodate Self Refresh operation. The reader shall note that the state may be in transition when an MRR is issued. A Read burst has been initiated, with Auto Precharge disabled.
Refresh requirements apply during clock frequency change;? No refresh operations are performed in power-down mode. System designers should use IBIS or other simulation tools to correlate the timing reference load to a system environment. To other circuitry like RCV, After issuing REFpb, these conditions must be met see Table 12 on page A Write burst has been initiated, with Auto Precharge disabled.
After calibration is complete, the ZQ ball circuitry is disabled to reduce power consumption. Internal data-mask loading is identical to data-bit loading to ensure matched system timing. Row addresses are used to determine which row to activate in the selected bank. However, as of the publication date of this standard, no statements regarding an assurance or refusal to license such patents or patent applications have been provided.
JEDEC 规范 LPDDR3_图文_百度文库
The DRAM will also disable termination during read operations. NOTE 3 The tolerance limits are specified after calibration with fixed voltage and temperature. NOTE 2 This parameter is not subject to production test. Upon exiting self-refresh or power-down, the device temperature status bits shall be no older than tTSI. When using the temperature sensor, the actual device case temperature may be higher than the TOPER specification Table 32 on page 79 that applies for the standard or elevated temperature ranges.
These settings may need to be adjusted to meet minimum timing requirements at the target clock frequency. Once tRP is met, the bank will be in the idle state.?
This article is about computer memory.
Lpddr3 power-down occurs when all banks are idle, this mode is referred to as idle power-down; if power-down occurs when there is a row active in any bank, this mode is referred to as active power-down. To accommodate drift rates and calculate the necessary interval between ZQCS commands, apply the following formula: Command Input Setup and Hold Timing 4. Self-Refresh Operation NOTE 1 Input clock frequency may be changed or can be stopped or floated during self-refresh, provided that upon exiting specificcation, the clock is stable and within specified limits for a minimum of 2 clocks of stable clock are provided and the clock frequency is between the minimum and sspecification frequency for the speed grade in use.
The following section provides detailed information covering device initialization, register definition, command description and device operation. LPDDR3 devices will also manage Self Refresh power consumption when the operating temperature changes, lower jedev low temperatures and higher at high temperatures. For a complete definition of the device behavior, the information provided by the state diagram should be integrated with the truth tables and timing specification.
C0 input is not present on CA bus. A single resistor can be used for each device or one resistor can be shared between multiple devices if the ZQ calibration timings for each device do not overlap.
If the clock frequency is not changed over this period, converting to clocks is done by dividing tFAW[ns] by tCK[ns], and rounding up to the next integer value. A functional representation of the on-die termination is shown in the figure below. In both cases, the ZQ specificatjon shall not change after power is applied to the device.
One mode register unit is used for the programming of segment mask bits up to 8 bits. Differential Input Voltage i. Dynamic random-access memory DRAM. The MRR command has a burst length of eight. No claims to be in conformance with this standard may be made unless all requirements stated in the standard are met.
Data mask timings match data bit timing, but are inputs only. JEDEC does not make any determination as to the validity or relevancy of such patents or patent applications.
LOW POWER DOUBLE DATA RATE 3 SDRAM (LPDDR3) | JEDEC
Allowable commands to the other banks are determined by its current state and Table 2, and according to Table 3. For bank masking bit assignments, see Mode Register 16 as described on page The clock must toggle at least twice during the tXSR time.
The REFab command must not be issued to the device until the following conditions have been met see Table 12 on page