MICRON MT46V32M4TG-75Z, MT46V16M8TG-75, MT46V8M16TG-8 Datasheet

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

‡

DOUBLE DATA RATE (DDR) SDRAM

FEATURES

•VDD = +2.5V ±0.2V, VDDQ = +2.5V ±0.2V

• Bidirectional data strobe (DQS) transmitted/ received with data, i.e., source-synchronous data capture (x16 has two – one per byte)

• Internal, pipelined double-data-rate (DDR) architecture; two data accesses per clock cycle

• Differential clock inputs (CK and CK#)

• Commands entered on each positive CK edge

• DQS edge-aligned with data for READs; centeraligned with data for WRITEs

• DLL to align DQ and DQS transitions with CK

• Four internal banks for concurrent operation

• Data mask (DM) for masking write data (x16 has two – one per byte)

• x16 has programmable IOL/IOH option

• Programmable burst lengths: 2, 4, or 8

• Auto precharge option

• Auto Refresh and Self Refresh Modes

• Longer lead TSOP for improved reliability (OCPL)

• 2.5V I/O (SSTL_2 compatible)

OPTIONS MARKING

• Configuration 32 Meg x 4 (8 Meg x 4 x 4 banks) 32M4 16 Meg x 8 (4 Meg x 8 x 4 banks) 16M8 8 Meg x 16 (2 Meg x 16 x 4 banks) 8M16

MT46V32M4 – 8 Meg x 4 x 4 banks MT46V16M8 – 4 Meg x 8 x 4 banks MT46V8M16 – 2 Meg x 16 x 4 banks

For the latest data sheet revisions, please refer to the Micron Web site: www.micron.com/datasheets

PIN ASSIGNMENT (TOP VIEW)

66-Pin TSOP

V

DD

DQ0

V

SS

V

DD

DQ1

V

SS

V

DD

V

WE# CAS# RAS#

CS#

BA0 BA1

A10/AP

V

NC

NC NC

NC

NC NC

NC

A0 A1 A2 A3

DD

Q

DD

x8x4

V

DQ0

V

DD

DQ1

V

SS

DQ2

V

DD

DQ3

V

SS

V

DD

V

DNU

WE# CAS# RAS#

CS#

BA0 BA1

A10/AP

V

DD

NC

NC NC

DD

NC

A0 A1 A2 A3

DD

Q

x16

V

DQ0

VDDQ

DQ1

DQ2

VssQ

DQ3

DQ4

VDDQ

DQ5

DQ6

VssQ

DQ7

V

DD

LDQS

V

DNU

LDM

WE# CAS# RAS#

CS#

BA0 BA1

A10/AP

V

1

DD

2 3 4 5 6 7 8 9 10 11 12 13 14

NC

15

Q

16 17

NC

18

DD

19 20 21 22 23 24 25

NC

26 27 28 29

A0

30

A1

31

A2

32

A3

33

DD

66 65 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34

x16 V

SS

DQ15

V

SS

DQ14 DQ13

V

DD

DQ12 DQ11

V

SS

DQ10 DQ9

V

DD

DQ8

NC V

SS

UDQS

DNU

V

REF

V

SS

UDM CK# CK CKE NC NC

A11 A9 A8 A7 A6 A5 A4

V

SS

Q

x8 x4

V

SS

DQ7

V

SS

Q NC

DQ6

V

DD

Q NC

DQ5

V

SS

Q NC

DQ4

V

DD

Q NC NC V

SS

Q

DQS

DNU

V

REF

V

SS

DM CK# CK CKE NC NC

A11 A9 A8 A7 A6 A5 A4

V

SS

V NC V

SS

NC

DQ3

V

DD

NC NC V

SS

NC

DQ2

V

DD

NC NC V

SS

DQS

DNU

V

REF

V

SS

DM CK# CK CKE NC NC

A11 A9 A8 A7 A6 A5 A4

V

SS

Q

• Plastic Package – OCPL 66-pin TSOP TG (400 mil width, 0.65mm pin pitch)

• Timing – Cycle Time

7.5ns @ CL = 2 (DDR266B)

7.5ns @ CL = 2.5 (DDR266B)

10ns @ CL = 2 (DDR200)

1

2

3

-75Z

-75

-8

Configuration 8 Meg x 4 x 4 banks 4 Meg x 8 x 4 banks 2 Meg x 16 x 4 banks Refresh Count 4K 4K 4K Row Addressing 4K (A0–A11) 4K (A0–A11) 4K (A0–A11) Bank Addressing 4 (BA0, BA1) 4 (BA0, BA1) 4 (BA0, BA1) Column Addressing 2K (A0–A9, A11) 1K (A0–A9) 512 (A0–A8)

32 Meg x 4 16 Meg x 8 8 Meg x 16

• Self Refresh Standard none

KEY TIMING PARAMETERS

Low Power L

SPEE D CLOCK RATE DATA-OUT ACCESS DQS-DQ

NOTE: 1. Supports PC2100 modules with 2-3-3 timing

2. Supports PC2100 modules with 2.5-3-3 timing

3. Supports PC1600 modules with 2-2-2 timing

‡ PRODUCTS AND SPECIFICATIONS DISCUSSED HEREIN ARE FOR EVALUATION AND REFERENCE PURPOSES ONLY AND ARE

SUBJECT TO CHANGE BY MICRON WITHOUT NOTICE. PRODUCTS ARE ONLY WARRANTED BY MICRON TO MEET MICRON’S

PRODUCTION DATA SHEET SPECIFICATIONS.

GRADE CL = 2** CL = 2.5** WINDOW* WINDOW SKEW

-75Z 133 MHz 133 MHz 2.5ns ±0.75ns +0.5ns

-75 100 MHz 133 MHz 2.5ns ±0.75ns +0.5ns

-8 100 MHz 125 MHz 3.4ns ±0.8ns +0.6ns

*Minimum clock rate @ CL = 2 (-75Z and -8) and CL = 2.5 (-75) **CL = CAS (Read) Latency

1

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

128MB DDR SDRAM PART NUMBERS

(Note: xx= -75, -75Z, or -8)

PART NUMBER CONFIGURATION I/O DRIVE LEVEL REFRESH OPTION

MT46V32M4TG-xx 32 Meg x 4 Full Drive Standard MT46V32M4TG-xxL 32 Meg x 4 Full Drive Low Power

MT46V16M8TG-xx 16 Me g x 8 Full Drive Standard MT46V16M8TG-xxL 16 Meg x 8 Full Drive Low Power

MT46V8M16TG-xx 8 Meg x 16 Programmable Drive Standard MT46V8M16TG-xxL 8 Meg x 16 Programmable Drive Low Power

GENERAL DESCRIPTION

The 128Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory containing 134,217,728 bits. It is internally configured as a quadbank DRAM.

The 128Mb DDR SDRAM uses a double data rate architecture to achieve high-speed operation. The double data rate architecture is essentially a 2n-prefetch architecture with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or write access for the 128Mb DDR SDRAM effectively consists of a single 2n-bit wide, one-clock-cycle data transfer at the internal DRAM core and two corresponding n-bit wide, one-half-clock-cycle data transfers at the I/O pins.

A bidirectional data strobe (DQS) is transmitted externally, along with data, for use in data capture at the receiver. DQS is a strobe transmitted by the DDR SDRAM during READs and by the memory controller during WRITEs. DQS is edge-aligned with data for READs and center-aligned with data for WRITEs. The x16 offering has two data strobes, one for the lower byte and one for the upper byte.

The 128Mb DDR SDRAM operates from a differential clock (CK and CK#); the crossing of CK going HIGH and CK# going LOW will be referred to as the positive edge of CK. Commands (address and control signals) are registered at every positive edge of CK. Input data is registered on both edges of DQS, and output data is referenced to both edges of DQS, as well as to both edges of CK.

Read and write accesses to the DDR SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a

programmed sequence. Accesses begin with the registration of an ACTIVE command, which is then followed by a READ or WRITE command. The address bits registered coincident with the ACTIVE command are used to select the bank and row to be accessed. The address bits registered coincident with the READ or WRITE command are used to select the bank and the starting column location for the burst access.

The DDR SDRAM provides for programmable READ or WRITE burst lengths of 2, 4, or 8 locations. An auto precharge function may be enabled to provide a selftimed row precharge that is initiated at the end of the burst access.

As with standard SDR SDRAMs, the pipelined, multibank architecture of DDR SDRAMs allows for concurrent operation, thereby providing high effective bandwidth by hiding row precharge and activation time.

An auto refresh mode is provided, along with a power-saving power-down mode. All inputs are compatible with the JEDEC Standard for SSTL_2. All full drive strength outputs are SSTL_2, Class II compatible.

NOTE 1: The functionality and the timing specifications

discussed in this data sheet are for the DLL-enabled mode of operation.

NOTE 2: Throughout the data sheet, the various figures and

text refer to DQs as “DQ.” The DQ term is to be interpreted as any and all DQ collectively, unless specifically stated otherwise. Additionally, the x16 is divided in to two bytes — the lower byte and upper byte. For the lower byte (DQ0 through DQ7) DM refers to LDM and DQS refers to LDQS; and for the upper byte (DQ8 through DQ15) DM refers to UDM and DQS refers to UDQS.

2

PIN DESCRIPTIONS

TSOP PIN NUMBERS SYMBOL TYPE DESCRIPTION

45, 46 CK, CK# Input Clock: CK and CK# are differential clock inputs. All address and

control input signals are sampled on the crossing of the positive edge of CK and negative edge of CK#. Output data (DQs and DQS) is referenced to the crossings of CK and CK#.

44 CKE Input Clock Enable: CKE HIGH activates and CKE LOW deactivates the

internal clock, input buffers and output drivers. Taking CKE LOW provides PRECHARGE POWER-DOWN and SELF REFRESH operations (all banks idle), or ACTIVE POWER-DOWN (row ACTIVE in any bank). CKE is synchronous for POWER-DOWN entry and exit, and for SELF REFRESH entry. CKE is asynchronous for SELF REFRESH exit and for disabling the outputs. CKE must be maintained HIGH throughout read and write accesses. Input buffers (excluding CK, CK# and CKE) are disabled during POWERDOWN. Input buffers (excluding CKE) are disabled during SELF REFRESH. CKE is an SSTL_2 input but will detect an LVCMOS LOW level after VDD is applied.

24 CS# Input Chip Select: CS# enables (registered LOW) and disables (regis-

tered HIGH) the command decoder. All commands are masked when CS# is registered HIGH. CS# provides for external bank selection on systems with multiple banks. CS# is considered part of the command code.

23, 22, 21 RAS#, CAS#, Input Command Inputs: RAS#, CAS#, and WE# (along with CS#) define the

WE# command being entered.

47 DM Input Input Data Mask: DM is an input mask signal for write data. Input

20, 47 LDM, UDM data is masked when DM is sampled HIGH along with that input data

during a WRITE access. DM is sampled on both edges of DQS. Although DM pins are input-only, the DM loading is designed to match that of DQ and DQS pins. For the x16 , LDM is DM for DQ0DQ7 and UDM is DM for DQ8-DQ15. Pin 20 is a NC on x4 and x8

26, 27 BA0, BA1 Input Bank Address Inputs: BA0 and BA1 define to which bank an

ACTIVE, READ, WRITE, or PRECHARGE command is being applied.

29-32, 35-40, A0–A11 Input Address Inputs: Provide the row address for ACTIVE commands, and

28, 41 the column address and auto precharge bit (A10) for READ/WRITE

commands, to select one location out of the memory array in the respective bank. A10 sampled during a PRECHARGE command determines whether the PRECHARGE applies to one bank (A10 LOW, bank selected by BA0, BA1) or all banks (A10 HIGH). The address inputs also provide the op-code during a MODE REGISTER SET command. BA0 and BA1 define which mode register (mode register or extended mode register) is loaded during the LOAD MODE REGISTER command.

2, 4, 5, 7, 8, 10,11, 13, 54 DQ 0–15 I/O Data Input/Output: Data bus for x16 (4, 7, 10, 13, 54, 57, 60, and 63

56, 57, 59, 60, 62, 63,65 are NC for x8), (2, 4, 7, 8,10, 13, 54, 57, 59, 60, 63, and 65 are NC

for x4).

2, 5, 8, 11, 56, 59, 62, 65 DQ0–7 I/O Data Input/Output: Data bus for x8 (2, 8, 59, and 65 are NC for x4).

5, 11, 56, 62 DQ0 –3 I/O Data Input/Output: Data bus for x4.

(continued on next page)

7

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

PIN DESCRIPTIONS (continued)

TSOP PIN NUMBERS SYMBOL TYPE DESCRIPTION

51 DQS I/O Data Strobe: Output with read data, input with write data. DQS is

16, 51 LDQS, UDQS edge-aligned with read data, centered in write data. It is used to

capture data. For the x16 , LDQS is DQS for DQ0-DQ7 and UDQS is DQS for DQ8-DQ15. Pin 16 is NC on x4 and x8.

3, 9, 15, 55, 61 VDDQ Supply DQ Power Supply: +2.5V ±0.2V. Isolated on the die for improved

noise immunity.

6, 12, 52, 58, 64 VSSQ Supply DQ Ground. Isolated on the die for improved noise immunity.

1, 18, 33 VDD Supply Power Supply: +2.5V ±0.2V.

34, 48, 66 VSS Supply Ground.

49 VREF Supply SSTL_2 reference voltage.

14, 17, 19, 25, NC – No Connect: These pins should be left unconnected.

42, 43, 53

50 DNU – Do Not Use: Must float to minimize noise.

RESERVED NC PINS

TSOP PIN NUMBERS SYMBOL TYPE DESCRIPTION

42 A12 I Address input for 256Mb and 512Mb devices. 17 A13 I Address input for 1Gb devices.

NOTE: 1. NC pins not listed may also be reserved for other uses now or in the future. This table simply defines specific NC pins

deemed to be of importance.

1

8

FUNCTIONAL DESCRIPTION

The 128Mb DDR SDRAM is a high-speed CMOS, dynamic random-access memory containing 134,217,728 bits. The 128Mb DDR SDRAM is internally configured as a quad-bank DRAM.

The 128Mb DDR SDRAM uses a double data rate architecture to achieve high-speed operation. The double data rate architecture is essentially a 2n-prefetch architecture, with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or write access for the 128Mb DDR SDRAM consists of a single 2n-bit wide, one-clock-cycle data transfer at the internal DRAM core and two corresponding n-bit wide, one-half-clock-cycle data transfers at the I/O pins.

Read and write accesses to the DDR SDRAM are burst oriented; accesses start at a selected location and continue for a programmed number of locations in a programmed sequence. Accesses begin with the registration of an ACTIVE command, which is then followed by a READ or WRITE command. The address bits registered coincident with the ACTIVE command are used to select the bank and row to be accessed (BA0, BA1 select the bank; A0-A11 select the row). The address bits registered coincident with the READ or WRITE command are used to select the starting column location for the burst access.

Prior to normal operation, the DDR SDRAM must be initialized. The following sections provide detailed information covering device initialization, register definition, command descriptions and device operation.

Initialization

DDR SDRAMs must be powered up and initialized in a predefined manner. Operational procedures other than those specified may result in undefined operation. Power must first be applied to VDD and VDDQ simultaneously, and then to VREF (and to the system VTT). VTT must be applied after VDDQ to avoid device latch-up, which may cause permanent damage to the device. VREF can be applied any time after VDDQ but is expected to be nominally coincident with VTT. Except for CKE, inputs are not recognized as valid until after VREF is applied. CKE is an SSTL_2 input but will detect an LVCMOS LOW level after VDD is applied. Maintaining an LVCMOS LOW level on CKE during power-up is required to ensure that the DQ and DQS outputs will be in the High-Z state, where they will remain until driven in normal operation (by a read access). After all power supply and reference voltages are stable, and the clock is stable, the DDR SDRAM requires a 200µs delay prior to applying an executable command.

Once the 200µs delay has been satisfied, a DESELECT or NOP command should be applied, and CKE should be brought HIGH. Following the NOP com-

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

mand, a PRECHARGE ALL command should be applied. Next a LOAD MODE REGISTER command should be issued for the extended mode register (BA1 LOW and BA0 HIGH) to enable the DLL, followed by another LOAD MODE REGISTER command to the mode register (BA0/BA1 both LOW) to reset the DLL and to program the operating parameters. Two-hundred clock cycles are required between the DLL reset and any READ command. A PRECHARGE ALL command should then be applied, placing the device in the all banks idle state.

Once in the idle state, two AUTO REFRESH cycles must be performed (tRFC must be satisfied.) Additionally, a LOAD MODE REGISTER command for the mode register with the reset DLL bit deactivated (i.e., to program operating parameters without resetting the DLL) is required. Following these requirements, the DDR SDRAM is ready for normal operation.

REGISTER DEFINITION

MODE REGISTER

The mode register is used to define the specific mode of operation of the DDR SDRAM. This definition includes the selection of a burst length, a burst type, a CAS latency and an operating mode, as shown in Figure 1. The mode register is programmed via the MODE REGISTER SET command (with BA0 = 0 and BA1 = 0) and will retain the stored information until it is programmed again or the device loses power (except for bit A8, which is self-clearing).

Reprogramming the mode register will not alter the contents of the memory, provided it is performed correctly. The mode register must be loaded (reloaded) when all banks are idle and no bursts are in progress, and the controller must wait the specified time before initiating the subsequent operation. Violating either of these requirements will result in unspecified operation.

Mode register bits A0-A2 specify the burst length, A3 specifies the type of burst (sequential or interleaved), A4-A6 specify the CAS latency, and A7-A11 specify the operating mode.

Burst Length

Read and write accesses to the DDR SDRAM are burst oriented, with the burst length being programmable, as shown in Figure 1. The burst length determines the maximum number of column locations that can be accessed for a given READ or WRITE command. Burst lengths of 2, 4, or 8 locations are available for both the sequential and the interleaved burst types.

9

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

Reserved states should not be used, as unknown operation or incompatibility with future versions may result.

When a READ or WRITE command is issued, a block of columns equal to the burst length is effectively selected. All accesses for that burst take place within this block, meaning that the burst will wrap within the block if a boundary is reached. The block is uniquely selected by A1-Ai when the burst length is set to two, by A2-Ai when the burst length is set to four and by A3-Ai when the burst length is set to eight (where Ai is the most significant column address bit for a given con-

0

-

A7

7

M6

0

1

M10

0

-

A6 A5 A4

654

M4

M5

0

1

0

1

0

1

0

1

M8

M9

0

1

-

A3A8A2A1A0

38210

M2

M3

0

1

M7

M6-M0

0

Valid

0

Valid

-

Address Bus

Burst LengthCAS Latency BT0*0*

M1

0

1

CAS Latency

Reserved

-

Mode Register (Mx)

Burst Length

M0

M3 = 0

0

Reserved

0

1

0

1

2

2.5

2

0

4

1

8

0

Reserved

1

Reserved

0

Reserved

1

Reserved

Burst Type

Sequential

Interleaved

Operating Mode

Normal Operation

Normal Operation/Reset DLL

All other states reserved

M3 = 1

Reserved

2

4

8

Reserved

BA1

13

* M13 and M12 (BA0 and BA1)

must be “0, 0” to select the

base mode register (vs. the

extended mode register).

A10

BA0

A11

11

10

12

Operating Mode

A9

9

M11

Figure 1

Mode Register Definition

figuration). The remaining (least significant) address bit(s) is (are) used to select the starting location within the block. The programmed burst length applies to both READ and WRITE bursts.

Burst Type

Accesses within a given burst may be programmed to be either sequential or interleaved; this is referred to as the burst type and is selected via bit M3.

The ordering of accesses within a burst is determined by the burst length, the burst type and the starting column address, as shown in Table 1.

TABLE 1

BURST DEFINITION

Burst Starting Column Order of Accesses Within a Burst

Length Address Type = Sequential Type = Interleaved

A0

2

4

A2 A1 A0

0 0 0 0-1-2-3-4-5-6-7 0-1-2-3-4-5-6-7 0 0 1 1-2-3-4-5-6-7-0 1-0-3-2-5-4-7-6 0 1 0 2-3-4-5-6-7-0-1 2-3-0-1-6-7-4-5

8

0 1 1 3-4-5-6-7-0-1-2 3-2-1-0-7-6-5-4 1 0 0 4-5-6-7-0-1-2-3 4-5-6-7-0-1-2-3 1 0 1 5-6-7-0-1-2-3-4 5-4-7-6-1-0-3-2 1 1 0 6-7-0-1-2-3-4-5 6-7-4-5-2-3-0-1 1 1 1 7-0-1-2-3-4-5-6 7-6-5-4-3-2-1-0

NOTE: 1. For a burst length of two, A1-Ai select the two-

data-element block; A0 selects the first access within the block.

2. For a burst length of four, A2-Ai select the fourdata-element block; A0-A1 select the first access within the block.

3. For a burst length of eight, A3-Ai select the eightdata-element block; A0-A2 select the first access within the block.

4. Whenever a boundary of the block is reached within a given sequence above, the following access wraps within the block.

0 0-1 0-1 1 1-0 1-0

A1 A0

0 0 0-1-2-3 0-1-2-3 0 1 1-2-3-0 1-0-3-2 1 0 2-3-0-1 2-3-0-1 1 1 3-0-1-2 3-2-1-0

10

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

Read Latency

The READ latency is the delay, in clock cycles, between the registration of a READ command and the availability of the first bit of output data. The latency can be set to 2 or 2.5 clocks, as shown in Figure 2.

If a READ command is registered at clock edge n, and the latency is m clocks, the data will be available nominally coincident with clock edge n + m. Table 2 indicates the operating frequencies at which each CAS latency setting can be used.

Reserved states should not be used as unknown operation or incompatibility with future versions may result.

CK#

CK

COMMAND

DQS

DQ

CK#

CK

COMMAND

DQS

DQ

T0 T1 T2 T2n T3 T3n

READ NOP NOP NOP

CL = 2

T0 T1 T2 T2n T3 T3n

READ NOP NOP NOP

CL = 2.5

TABLE 2

CAS LATENCY (CL)

ALLOWABLE OPERATING

FREQUENCY (MHz)

SPEED CL = 2 CL = 2.5

-75Z 75 ≤ f ≤ 133 75 ≤ f ≤133

-75 75 ≤ f ≤ 100 75 ≤ f ≤133

-8 75 ≤ f ≤ 100 75 ≤ f ≤125

Operating Mode

The normal operating mode is selected by issuing a MODE REGISTER SET command with bits A7-A11 each set to zero, and bits A0-A6 set to the desired values. A DLL reset is initiated by issuing a MODE REGISTER SET command with bits A7 and A9-A11 each set to zero, bit A8 set to one, and bits A0-A6 set to the desired values. Although not required by the Micron device, JEDEC specifications recommend when a LOAD MODE REGISTER command is issued to reset the DLL, it should always be followed by a LOAD MODE REGISTER command to select normal operating mode.

All other combinations of values for A7-A11 are reserved for future use and/or test modes. Test modes and reserved states should not be used because unknown operation or incompatibility with future versions may result.

Burst Length = 4 in the cases shown Shown with nominal tAC and nominal tDSDQ

DON’T CARETRANSITIONING DATA

Figure 2

CAS Latency

11

EXTENDED MODE REGISTER

Operating Mode

Normal Operation

All other states reserved

0–0

–

Valid

–

0

1

DLL

Enable

Disable

DLL

110

1

A9

A7

A6 A5 A4

A3A8A2A1A0

Extended Mode Register (Ex)

Address Bus

9

7

654

382

1

0

E0

0

1

Drive Strength

Normal

Reduced

E1

2

0

–

QFC Function

Disabled

Reserved

E2

3

E0

E1,

Operating Mode

A10

A11

BA1

BA0

10

11

12

13

Notes: 1. E13 and E12 (BA0 and BA1) must be “1, 0” to select the

Extended Mode Register (vs. the base Mode Register).

2. The reduced drive strength option is not supported on the x4 and x8 versions and is only available on the D3 version of the x16 device.

3. The QFC option is not supported.

E2,E3E4

0–0–0–0

–

0

–

E6E5E7E8E9

0–0

–

E10E11

DSQFC

The extended mode register controls functions beyond those controlled by the mode register; these additional functions are DLL enable/disable, output drive strength, and QFC#. These functions are controlled via the bits shown in Figure 3. The extended mode register is programmed via the LOAD MODE REGISTER command to the mode register (with BA0 = 1 and BA1 = 0) and will retain the stored information until it is programmed again or the device loses power. The enabling of the DLL should always be followed by a LOAD MODE REGISTER command to the mode register (BA0/BA1 both LOW) to reset the DLL.

The extended mode register must be loaded when all banks are idle and no bursts are in progress, and the controller must wait the specified time before initiating any subsequent operation. Violating either of these requirements could result in unspecified operation.

Output Drive Strength

The normal full drive strength for all outputs are specified to be SSTL2, Class II. The x16 supports an option for reduced drive. This option is intended for the support of the lighter load and/or point-to-point environments. The selection of the reduced drive strength will alter the DQs and DQSs from SSTL2, Class II drive strength to a reduced drive strength, which is approximately 54 percent of the SSTL2, Class II drive strength.

The Micron 128Mb (8 Meg x16) device supports a programmable drive strength option.

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

DLL Enable/Disable

The DLL must be enabled for normal operation. DLL enable is required during power-up initialization and upon returning to normal operation after having disabled the DLL for the purpose of debug or evaluation. (When the device exits self refresh mode, the DLL is enabled automatically.) Any time the DLL is enabled, 200 clock cycles must occur before a READ command can be issued.

Figure 3

Extended Mode Register Definition

12

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

Commands

Truth Table 1 provides a quick reference of available commands. This is followed by a verbal description of each command. Two additional Truth Tables

TRUTH TABLE 1 – COMMANDS

(Note: 1)

NAME (FUNCTION) CS# RAS# CAS# WE# ADDR NOTES

DESELECT (NOP) H X X X X 9

NO OPERATION (NOP) L H H H X 9

ACTIVE (Select bank and activate row) L L H H Bank/Row 3

READ (Select bank and column, and start READ burst) L H L H Bank/Col 4

WRITE (Select bank and column, and start WRITE burst) L H L L Bank/Col 4

BURST TERMINATE L H H L X 8

PRECHARGE (Deactivate row in bank or banks) L L H L Code 5

AUTO REFRESH or SELF REFRESH L L L H X 6, 7 (Enter self refresh mode)

LOAD MODE REGISTER L L L L Op-Code 2

appear following the Operation section; these tables provide current state/next state information.

TRUTH TABLE 1A – DM OPERATION

NAME (FUNCTION) DM DQs NOTES

Write Enable L Valid 10

Write Inhibit HX 10

NOTE: 1. CKE is HIGH for all commands shown except SELF REFRESH.

2. BA0-BA1 select either the mode register or the extended mode register (BA0 = 0, BA1 = 0 select the mode register; BA0 = 1, BA1 = 0 select extended mode register; other combinations of BA0-BA1 are reserved). A0-A11 provide the op-code to be written to the selected mode register.

3. BA0-BA1 provide bank address and A0-A11 provide row address.

4. BA0-BA1 provide bank address; A0-Ai provide column address (where i = 8 for x16, 9 for x8, and 9, 11 for x4); A10 HIGH enables the auto precharge feature (nonpersistent), and A10 LOW disables the auto precharge feature.

5. A10 LOW: BA0-BA1 determine which bank is precharged. A10 HIGH: all banks are precharged and BA0-BA1 are “Don’t Care.”

6. This command is AUTO REFRESH if CKE is HIGH, SELF REFRESH if CKE is LOW.

7. Internal refresh counter controls row addressing; all inputs and I/Os are “Don’t Care” except for CKE.

8. Applies only to read bursts with auto precharge disabled; this command is undefined (and should not be used) for READ bursts with auto precharge enabled and for WRITE bursts.

9. DESELECT and NOP are functionally interchangeable.

10. Used to mask write data; provided coincident with the corresponding data.

13

DESELECT

The DESELECT function (CS# HIGH) prevents new commands from being executed by the DDR SDRAM. The DDR SDRAM is effectively deselected. Operations already in progress are not affected.

NO OPERATION (NOP)

The NO OPERATION (NOP) command is used to instruct the selected DDR SDRAM to perform a NOP (CS# LOW). This prevents unwanted commands from being registered during idle or wait states. Operations already in progress are not affected.

LOAD MODE REGISTER

The mode registers are loaded via inputs A0-A11. See mode register descriptions in the Register Definition section. The LOAD MODE REGISTER command can only be issued when all banks are idle, and a subsequent executable command cannot be issued until

t

MRD is met.

ACTIVE

The ACTIVE command is used to open (or activate) a row in a particular bank for a subsequent access. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0-A11 selects the row. This row remains active (or open) for accesses until a PRECHARGE command is issued to that bank. A PRECHARGE command must be issued before opening a different row in the same bank.

READ

The READ command is used to initiate a burst read access to an active row. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0-Ai (where i = 8 for x16, 9 for x8, or 9, 11 for x4) selects the starting column location. The value on input A10 determines whether or not auto precharge is used. If auto precharge is selected, the row being accessed will be precharged at the end of the READ burst; if auto precharge is not selected, the row will remain open for subsequent accesses.

WRITE

The WRITE command is used to initiate a burst write access to an active row. The value on the BA0, BA1 inputs selects the bank, and the address provided on inputs A0Ai (where i = 8 for x16, 9 for x8, or 9, 11 for x4) selects the starting column location. The value on input A10 determines whether or not auto precharge is used. If auto precharge is selected, the row being accessed will be precharged at the end of the WRITE burst; if auto precharge is not selected, the row will remain open for subsequent accesses. Input data appearing on the DQs is written to

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

the memory array subject to the DM input logic level appearing coincident with the data. If a given DM signal is registered LOW, the corresponding data will be written to memory; if the DM signal is registered HIGH, the corresponding data inputs will be ignored, and a WRITE will not be executed to that byte/column location.

PRECHARGE

The PRECHARGE command is used to deactivate the open row in a particular bank or the open row in all banks. The bank(s) will be available for a subsequent row access a specified time (tRP) after the PRECHARGE command is issued. Input A10 determines whether one or all banks are to be precharged, and in the case where only one bank is to be precharged, inputs BA0, BA1 select the bank. Otherwise BA0, BA1 are treated as “Don’t Care.” Once a bank has been precharged, it is in the idle state and must be activated prior to any READ or WRITE commands being issued to that bank. A PRECHARGE command will be treated as a NOP if there is no open row in that bank (idle state), or if the previously open row is already in the process of precharging.

AUTO PRECHARGE

Auto precharge is a feature which performs the same individual-bank precharge function described above, but without requiring an explicit command. This is accomplished by using A10 to enable auto precharge in conjunction with a specific READ or WRITE command. A precharge of the bank/row that is addressed with the READ or WRITE command is automatically performed upon completion of the READ or WRITE burst. Auto precharge is nonpersistent in that it is either enabled or disabled for each individual READ or WRITE command.

Auto precharge ensures that the precharge is initiated at the earliest valid stage within a burst. This “earliest valid stage” is determined as if an explicit PRECHARGE command was issued at the earliest possible time, without violating tRAS(MIN), as described for each burst type in the Operation section of this data sheet. The user must not issue another command to the same bank until the precharge time (tRP) is completed.

BURST TERMINATE

The BURST TERMINATE command is used to truncate READ bursts (with auto precharge disabled). The most recently registered READ command prior to the BURST TERMINATE command will be truncated, as shown in the Operation section of this data sheet. The open page which the READ burst was terminated from remains open.

14

AUTO REFRESH

AUTO REFRESH is used during normal operation of the DDR SDRAM and is analogous to CAS#-BEFORE-RAS# (CBR) REFRESH in FPM/EDO DRAMs. This command is nonpersistent, so it must be issued each time a refresh is required.

The addressing is generated by the internal refresh controller. This makes the address bits a “Don’t Care” during an AUTO REFRESH command. The 128Mb DDR SDRAM requires AUTO REFRESH cycles at an average interval of 15.625µs (maximum).

To allow for improved efficiency in scheduling and switching between tasks, some flexibility in the absolute refresh interval is provided. A maximum of eight AUTO REFRESH commands can be posted to any given DDR SDRAM, meaning that the maximum absolute interval between any AUTO REFRESH command and the next AUTO REFRESH command is 9 x 15.6µs (140.6µs). This maximum absolute interval is to allow future support for DLL updates internal to the DDR SDRAM to be restricted to AUTO REFRESH cycles, without allowing excessive drift in

t

AC between updates.

Although not a JEDEC requirement, to provide for future functionality features, CKE must be active (High) during the AUTO REFRESH period. The AUTO RE-

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

FRESH period begins when the AUTO REFRESH command is registered and ends

SELF REFRESH

The SELF REFRESH command can be used to retain data in the DDR SDRAM, even if the rest of the system is powered down. When in the self refresh mode, the DDR SDRAM retains data without external clocking. The SELF REFRESH command is initiated like an AUTO REFRESH command except CKE is disabled (LOW). The DLL is automatically disabled upon entering SELF REFRESH and is automatically enabled upon exiting SELF REFRESH (200 clock cycles must then occur before a READ command can be issued). Input signals except CKE are “Don’t Care” during SELF REFRESH.

The procedure for exiting self refresh requires a sequence of commands. First, CK must be stable prior to CKE going back HIGH. Once CKE is HIGH, the DDR SDRAM must have NOP commands issued for

t

XSNR because time is required for the completion of any internal refresh in progress. A simple algorithm for meeting both refresh and DLL requirements is to apply NOPs for 200 clock cycles before applying any other command.

t

RFC later.

15

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

Operations

BANK/ROW ACTIVATION

Before any READ or WRITE commands can be issued to a bank within the DDR SDRAM, a row in that bank must be “opened.” This is accomplished via the ACTIVE command, which selects both the bank and the row to be activated, as shown in Figure 4.

After a row is opened with an ACTIVE command, a READ or WRITE command may be issued to that row, subject to the tRCD specification. tRCD (MIN) should be divided by the clock period and rounded up to the next whole number to determine the earliest clock edge after the ACTIVE command on which a READ or WRITE command can be entered. For example, a tRCD specification of 20ns with a 133 MHz clock (7.5ns period) results in 2.7 clocks rounded to 3. This is reflected in Figure 5, which covers any case where 2 < tRCD (MIN)/tCK ≤ 3. (Figure 5 also shows the same case for tRCD; the same procedure is used to convert other specification limits from time units to clock cycles).

A subsequent ACTIVE command to a different row in the same bank can only be issued after the previous active row has been “closed” (precharged). The minimum time interval between successive ACTIVE commands to the same bank is defined by tRC.

A subsequent ACTIVE command to another bank can be issued while the first bank is being accessed, which results in a reduction of total row-access overhead. The minimum time interval between successive ACTIVE commands to different banks is defined by

t

RRD.

CK#

CK

CKE

HIGH

CS#

RAS#

CAS#

WE#

A0-A11

BA0,1

RA

BA

RA = Row Address BA = Bank Address

Figure 4

Activating a Specific Row in

a Specific Bank

CK#

CK

COMMAND

A0-A11

BA0, BA1

T0 T1 T2 T3 T4 T5 T6 T7

ACT ACT

Row Row

Bank x Bank y

NOP

t

NOP

RRD

NOP

t

NOP

RCD

RD/WR

Col

Bank y

DON’T CARE

NOP

Figure 5

Example: Meeting tRCD (tRRD) MIN When 2 < tRCD (tRRD) MIN/tCK < 3

16

READS

READ bursts are initiated with a READ command, as shown in Figure 6.

The starting column and bank addresses are provided with the READ command and auto precharge is either enabled or disabled for that burst access. If auto precharge is enabled, the row being accessed is precharged at the completion of the burst. For the generic READ commands used in the following illustrations, auto precharge is disabled.

During READ bursts, the valid data-out element from the starting column address will be available following the CAS latency after the READ command. Each subsequent data-out element will be valid nominally at the next positive or negative clock edge (i.e., at the next crossing of CK and CK#). Figure 7 shows general timing for each possible CAS latency setting. DQS is driven by the DDR SDRAM along with output data. The initial LOW state on DQS is known as the read preamble; the LOW state coincident with the last data-out element is known as the read postamble.

Upon completion of a burst, assuming no other commands have been initiated, the DQs will go High-Z. A detailed explanation of tDQSQ (valid dataout skew), tQH (data-out window hold), the valid data window are depicted in Figure 27. A detailed explanation of tDQSCK (DQS transition skew to CK) and tAC (data-out transition skew to CK) is depicted in Figure 28.

Data from any READ burst may be concatenated with or truncated with data from a subsequent READ command. In either case, a continuous flow of data can be maintained. The first data element from the new burst follows either the last element of a completed burst or the last desired data element of a longer burst which is being truncated. The new READ command should be issued x cycles after the first READ command, where x equals the number of desired data element pairs (pairs are required by the 2n-prefetch architecture). This is shown in Figure 8. A READ command can be initiated on any clock cycle following a previous READ command. Nonconsecutive read data is shown for illustration in Figure 9. Full-speed random read accesses within a page (or pages) can be performed as shown in Figure 10.

CK#

CK

CKE

CS#

RAS#

CAS#

WE#

x4: A0–A9, A11

x8: A0–A9

x16: A0–A8

x8: A11

x16: A9, A11

A10

BA0,1

CA = Column Address BA = Bank Address EN AP = Enable Auto Precharge DIS AP = Disable Auto Precharge

READ Command

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

HIGH

CA

EN AP

DIS AP

BA

DON’T CARE

Figure 6

17

CK#

CK

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

T0 T1 T2 T3T2n T3n T4 T5

COMMAND

ADDRESS

DQS

DQ

CK#

CK

COMMAND

ADDRESS

DQS

DQ

READ NOP NOP NOP NOP NOP

Bank a,

Col n

CL = 2

DO

n

T0 T1 T2 T3T2n T3n T4 T5

READ NOP NOP NOP NOP NOP

Bank a,

Col n

CL = 2.5

DO

n

NOTE: 1. DO n = data-out from column n.

DON’T CARE TRANSITIONING DATA

2. Burst length = 4.

3. Three subsequent elements of data-out appear in the programmed order following DO n.

4. Shown with nominal tAC, tDQSCK, and tDQSQ.

Figure 7

READ Burst

18

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

CK#

CK

COMMAND

ADDRESS

DQS

DQ

CK#

CK

COMMAND

ADDRESS

T0 T1 T2 T3T2n T3n T4 T5T4n T5n

READ NOP READ NOP NOP NOP

Bank,

Col n

Bank, Col b

CL = 2

DO

n

DO

b

T0 T1 T2 T3T2n T3n T4 T5T4n T5n

READ NOP READ NOP NOP NOP

Bank,

Col n

Bank, Col b

CL = 2.5

DQS

DQ

DO

n

DO

b

DON’T CARE TRANSITIONING DATA

NOTE: 1. DO n (or b) = data-out from column n (or column b).

2. Burst length = 4 or 8 (if 4, the bursts are concatenated; if 8, the second burst interrupts the first).

3. Three subsequent elements of data-out appear in the programmed order following DO n.

4. Three (or seven) subsequent elements of data-out appear in the programmed order following DO b.

5. Shown with nominal

t

AC, tDQSCK, and tDQSQ.

6. Example applies only when READ commands are issued to same device.

Figure 8

Consecutive READ Bursts

19

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

CK#

CK

COMMAND

ADDRESS

DQS

DQ

CK#

CK

COMMAND

ADDRESS

DQS

T0 T1 T2 T3T2n T3n T4 T5 T5n T6

READ NOP NOP NOP NOP NOP

Bank,

Col n

READ

Bank, Col b

CL = 2

DO

n

DO

b

T0 T1 T2 T3T2n T3n T4 T5 T5n T6

READ NOP NOP NOP NOP NOP

Bank,

Col n

READ

Bank, Col b

CL = 2.5

DQ

DO

n

DO

b

DON’T CARE TRANSITIONING DATA

NOTE: 1. DO n (or b) = data-out from column n (or column b).

2. Burst length = 4 or 8 (if 4, the bursts are concatenated; if 8, the second burst interrupts the first).

3. Three subsequent elements of data-out appear in the programmed order following DO n.

4. Three (or seven) subsequent elements of data-out appear in the programmed order following DO b.

5. Shown with nominal

t

AC, tDQSCK, and tDQSQ.

6. Example applies when READ commands are issued to different devices or nonconsecutive READs.

Figure 9

Nonconsecutive READ Bursts

20

CK#

CK

PRELIMINARY

128Mb: x4, x8, x16

DDR SDRAM

T0 T1 T2 T3T2n T3n T4 T5T4n T5n

COMMAND

ADDRESS

DQS

DQ

CK#

CK

COMMAND

ADDRESS

DQS

READ READ READ NOP NOP

Bank,

Col n

Bank,

Col x

Bank,

Col b

READ

Bank,

Col g

CL = 2

DO

n

DO

n'

DO

x

DO

x'

DO

b

DO

b'

DO

g

T0 T1 T2 T3T2n T3n T4 T5T4n T5n

READ READ READ NOP NOP

Bank,

Col n

Bank,

Col x

Bank,

Col b

READ

Bank,

Col g

CL = 2.5

DQ

DO

n

DO

n'

DO

x

DO

x'

DO

b

DO

b'

DON’T CARE TRANSITIONING DATA

NOTE: 1. DO n (or x or b or g) = data-out from column n (or column x or column b or column g).

2. Burst length = 2 or 4 or 8 (if 4 or 8, the following burst interrupts the previous).

3. n' or x' or b' or g' indicates the next data-out following DO n or DO x or DO b or DO g, respectively.

4. READs are to an active row in any bank.

t

5. Shown with nominal

AC, tDQSCK, and tDQSQ.

Figure 10

Random READ Accesses

21

MICRON MT46V32M4TG-75Z, MT46V16M8TG-75, MT46V8M16TG-8 Datasheet

Specifications and Main Features

Frequently Asked Questions

User Manual

FEATURES

OPTIONS MARKING

PIN ASSIGNMENT (TOP VIEW)

KEY TIMING PARAMETERS

128MB DDR SDRAM PART NUMBERS

GENERAL DESCRIPTION

TABLE OF CONTENTS

32 Meg x 4

16 Meg x 8

8 Meg x 16

PIN DESCRIPTIONS

RESERVED NC PINS

FUNCTIONAL DESCRIPTION

Initialization

REGISTER DEFINITION

MODE REGISTER

Burst Length

Burst Type

Read Latency

Operating Mode

EXTENDED MODE REGISTER

Output Drive Strength

DLL Enable/Disable

Commands

DESELECT

NO OPERATION (NOP)

LOAD MODE REGISTER

ACTIVE

READ

WRITE

PRECHARGE

AUTO PRECHARGE

BURST TERMINATE

AUTO REFRESH

SELF REFRESH

Operations

BANK/ROW ACTIVATION

READS