AS4C256M8D3A-12BAN
Revision History
2Gb AS4C256M8D3A-12BAN - 78 ball FBGA PACKAGE
Revision
Rev 1.0
Details
Preliminary datasheet
Date
May. 2016
Alliance Memory Inc. 511 Taylor Way, San Carlos, CA 94070 TEL: (650) 610-6800 FAX: (650) 620-9211
Alliance Memory Inc. reserves the right to change products or specification without notice
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AS4C256M8D3A-12BAN
256M x 8 bit DDR3 Synchronous DRAM (SDRAM)
Features
Overview
JEDEC Standard Compliant
Power supplies: VDD & VDDQ = +1.5V 0.075V
Automotive temperature: TC = -40~105°C
AEC-Q100 Compliant
Supports JEDEC clock jitter specification
Fully synchronous operation
Fast clock rate: 800MHz
Differential Clock, CK & CK#
Bidirectional differential data strobe
- DQS & DQS#
8 internal banks for concurrent operation
8n-bit prefetch architecture
Pipelined internal architecture
Precharge & active power down
Programmable Mode & Extended Mode registers
Additive Latency (AL): 0, CL-1, CL-2
Programmable Burst lengths: 4, 8
Burst type: Sequential / Interleave
Output Driver Impedance Control
8192 refresh cycles / 64ms
- Average refresh period
7.8μs @ -40°C ≦TC≦ +85°C
3.9μs @ +85°C≦TC≦ +105°C
Write Leveling
ZQ Calibration
Dynamic ODT (Rtt_Nom & Rtt_WR)
RoHS compliant
Auto Refresh and Self Refresh
78-ball 8 x 10.5 x 1.0mm FBGA package
- Pb and Halogen Free
The 2Gb Double-Data-Rate-3 DRAMs is double data
rate architecture to achieve high-speed operation. It is
internally configured as an eight bank DRAM.
The 2Gb chip is organized as 32Mbit x 8 I/Os x 8 bank
devices. These synchronous devices achieve high
speed double-data-rate transfer rates of up to 1866
Mb/sec/pin for general applications.
The chip is designed to comply with all key DDR3
DRAM key features and all of the control and address
inputs are synchronized with a pair of externally
supplied differential clocks. Inputs are latched at the
cross point of differential clocks (CK rising and CK#
falling). All I/Os are synchronized with differential DQS
pair in a source synchronous fashion.
These devices operate with a single 1.5V ± 0.075V
power supply and are available in BGA packages.
Table 1. Ordering Information
Product part No
AS4C256M8D3A-12BAN
Org
Temperature
Max Clock (MHz)
Package
800
78-ball FBGA
256M x 8 Automotive -40°C to 105°C
Table 2. Speed Grade Information
Speed Grade
Clock Frequency
CAS Latency
tRCD (ns)
tRP (ns)
DDR3-1600
800 MHz
11
13.75
13.75
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Figure 1. Ball Assignment (FBGA Top View)
…
1
2
3
7
8
9
A
VSS
VDD
NC
TDQS#
VSS
VDD
B
VSS
VSSQ
DQ0
DM/
TDQS .
VSSQ
VDDQ
C
VDDQ
DQ2
DQS
DQ1
DQ3
VSSQ
D
VSSQ
DQ6
DQS#
VDD
VSS
VSSQ
E
VREFDQ
VDDQ
DQ4
DQ7
DQ5
VDDQ
F
NC
VSS
RAS#
CK
VSS
NC
G
ODT
VDD
CAS#
CK#
VDD
CKE
H
NC
CS#
WE#
A10/AP
ZQ
NC
J
VSS
BA0
BA2
NC
VREFCA
VSS
K
VDD
A3
A0
A12/BC#
BA1
VDD
L
VSS
A5
A2
A1
A4
VSS
M
VDD
A7
A9
A11
A6
VDD
N
VSS
RESET#
A13
A14
A8
VSS
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Figure 2. Block Diagram
Row
Decoder
DLL
CLOCK
BUFFER
CK
CK#
CKE
32M x 8
CELL ARRAY
(BANK #0)
Column Decoder
CS#
RAS#
CAS#
WE#
32M x 8
CELL ARRAY
(BANK #1)
Column Decoder
Row
Decoder
COMMAND
DECODER
CONTROL
SIGNAL
GENERATOR
Row
Decoder
RESET#
32M x 8
CELL ARRAY
(BANK #2)
Column Decoder
COLUMN
COUNTER
MODE
REGISTER
Row
Decoder
A10/AP
A12/BC#
32M x 8
CELL ARRAY
(BANK #3)
Column Decoder
A0-A9
A11
A13-A14
BA0-BA2
Row
Decoder
ZQ
CAL
ZQCL
ZQCS
32M x 8
CELL ARRAY
(BANK #5)
Column Decoder
RZQ
DATA
STROBE
BUFFER
DQ
Buffer
Row
Decoder
DQS
DQS#
TDQS
TDQS#
32M x 8
CELL ARRAY
(BANK #4)
Column Decoder
REFRESH
COUNTER
VSSQ
Row
Decoder
ADDRESS
BUFFER
32M x 8
CELL ARRAY
(BANK #6)
Column Decoder
Row
Decoder
~
DQ0
DQ7
ODT
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DM
32M x 8
CELL ARRAY
(BANK #7)
Column Decoder
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AS4C256M8D3A-12BAN
Figure 3. State Diagram
This simplified State Diagram is intended to provide an overview of the possible state transitions and the commands
to control them. In particular, situations involving more than one bank, the enabling or disabling of on-die termination,
and some other events are not captured in full detail.
Power
On
Reset
Procedure
from any
RESET
state
ZQCL
PRE = Precharge
PREA = Precharge All
Self
Refresh
MRS
ZQCL,ZQCS
Active
Power
Down
Idle
REF
ACT
E
PD X
PD
ZQ
Calibration
ACT = Active
MRS,MPR,
Write
Leveling
Initialization
SR
SR E
X
Power
applied
Precharge
Power
Down
Activating
PD
X
MRS = Mode Register Set
PD
E
REF = Refresh
RESET = Start RESET Procedure
Bank
Activating
Read = RD, RDS4, RDS8
Read A = RDA, RDAS4, RDAS8
ZQCS = ZQ Calibration Short
EA
WRITE
RE
Writing
AD
RE
READ A
ITE
WR
A
RE
A
PR
E
Reading
A
RE
,P
EA
PR
Automatic Sequence
Command Sequence
DA
PRE, PREA
E,
PR
Writing
Reading
A
WRITE A
MPR = Multi-Purpose Register
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READ
READ
WRITE
PDE = Enter Power-down
PDX = Exit Power-down
SRE = Self-Refresh entry
SRX = Self-Refresh exit
AD
WR
IT
TE
ZQCL = ZQ Calibration Long
RI
Write A = WRA, WRAS4, WRAS8
W
Write = WR, WRS4, WRS8
Refreshing
Precharging
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AS4C256M8D3A-12BAN
Ball Descriptions
Table 3. Ball Descriptions
Symbol
Type
Description
CK, CK#
Input
Differential Clock: CK and CK# are driven by the system clock. All SDRAM input signals
are sampled on the crossing of positive edge of CK and negative edge of CK#. Output
(Read) data is referenced to the crossings of CK and CK# (both directions of crossing).
CKE
Input
Clock Enable: CKE activates (HIGH) and deactivates (LOW) the CK signal. If CKE goes
LOW synchronously with clock, the internal clock is suspended from the next clock cycle
and the state of output and burst address is frozen as long as the CKE remains LOW.
When all banks are in the idle state, deactivating the clock controls the entry to the Power
Down and Self Refresh modes.
BA0-BA2
Input
Bank Address: BA0-BA2 define to which bank the BankActivate, Read, Write, or Bank
Precharge command is being applied.
A0-A14
Input
Address Inputs: A0-A14 are sampled during the BankActivate command (row address
A0-A14) and Read/Write command (column address A0-A9 with A10 defining Auto
Precharge).
A10/AP
Input
Auto-Precharge: A10 is sampled during Read/Write commands to determine whether
Autoprecharge should be performed to the accessed bank after the Read/Write operation.
(HIGH: Autoprecharge; LOW: no Autoprecharge). A10 is sampled during a Precharge
command to determine whether the Precharge applies to one bank (A10 LOW) or all
banks (A10 HIGH).
A12/BC#
Input
Burst Chop: A12/BC# is sampled during Read and Write commands to determine if burst
chop (on the fly) will be performed. (HIGH - no burst chop; LOW - burst chopped).
CS#
Input
Chip Select: CS# enables (sampled LOW) and disables (sampled HIGH) the command
decoder. All commands are masked when CS# is sampled HIGH. It is considered part of
the command code.
RAS#
Input
Row Address Strobe: The RAS# signal defines the operation commands in conjunction
with the CAS# and WE# signals and is latched at the crossing of positive edges of CK and
negative edge of CK#. When RAS# and CS# are asserted "LOW" and CAS# is asserted
"HIGH" either the BankActivate command or the Precharge command is selected by the
WE# signal. When the WE# is asserted "HIGH" the BankActivate command is selected
and the bank designated by BA is turned on to the active state. When the WE# is asserted
"LOW" the Precharge command is selected and the bank designated by BA is switched to
the idle state after the precharge operation.
CAS#
Input
Column Address Strobe: The CAS# signal defines the operation commands in conjunction
with the RAS# and WE# signals and is latched at the crossing of positive edges of CK and
negative edge of CK#. When RAS# is held "HIGH" and CS# is asserted "LOW" the column
access is started by asserting CAS# "LOW". Then, the Read or Write command is selected
by asserting WE# "HIGH" or "LOW".
WE#
Input
Write Enable: The WE# signal defines the operation commands in conjunction with the
RAS# and CAS# signals and is latched at the crossing of positive edges of CK and
negative edge of CK#. The WE# input is used to select the BankActivate or Precharge
command and Read or Write command.
DQS,
Input /
DQS#
Output
Bidirectional Data Strobe: Specifies timing for Input and Output data. Read Data Strobe
is edge triggered. Write Data Strobe provides a setup and hold time for data and DM. The
data strobes DOS is paired with DQS# to provide differential pair signaling to the system
during both reads and writes.
TDQS
Output
Termination Data Strobe: When TDQS is enabled, DM is disabled, and the TDQS and
TDQS# balls provide termination resistance.
Input
Data Input Mask: Input data is masked when DM is sampled HIGH during a write cycle.
DM has an optional use as TDQS on the x8.
TDQS#
DM
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DQ0 – DQ7
Input /
Output
Data I/O: The DQ0-DQ7 input and output data are synchronized with positive and negative
edges of DQS and DQS#. The I/Os are byte-maskable during Writes.
ODT
Input
On Die Termination: ODT (registered HIGH) enables termination resistance internal to
the DDR3 SDRAM. When enabled, ODT is applied to each DQ, DQS, DQS#, DM/TDQS
and TDQS# signal. (When TDQS is enabled via Mode Register A11=1 in MR1) The ODT
pin will be ignored if Mode-registers, MR1and MR2, are programmed to disable RTT.
RESET#
Input
Active Low Asynchronous Reset: Reset is active when RESET# is LOW, and inactive
when RESET# is HIGH. RESET# must be HIGH during normal operation. RESET# is a
CMOS rail to rail signal with DC high and low at 80% and 20% of VDD
VDD
Supply
Power Supply: +1.5V 0.075V
VSS
Supply
Ground
VDDQ
Supply
DQ Power: +1.5V 0.075V.
VSSQ
Supply
DQ Ground
VREFCA
Supply
Reference voltage for CA
VREFDQ
Supply
Reference voltage for DQ
ZQ
Supply
Reference pin for ZQ calibration.
NC
-
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No Connect: These pins should be left unconnected.
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Operation Mode Truth Table
Command
Table 4. Truth Table (Note (1), (2))
State CKEn-1(3) CKEn DM BA0-2 A10/AP A0-9, 11, 13-14 A12/BC# CS#
Idle(4)
H
H
X
V
Single Bank Precharge
Any
H
H
X
V
L
V
All Banks Precharge
Any
H
H
X
V
H
V
Write (Fixed BL8 or BC4)
Active(4)
H
H
X
V
L
Write (BC4, on the fly)
Active(4)
H
H
X
V
Write (BL8, on the fly)
Active(4)
H
H
X
Active(4)
H
H
Active(4)
H
Active(4)
Read (Fixed BL8 or BC4)
WE#
L
L
H
H
V
L
L
H
L
V
L
L
H
L
V
V
L
H
L
L
L
V
L
L
H
L
L
V
L
V
H
L
H
L
L
X
V
H
V
V
L
H
L
L
H
X
V
H
V
L
L
H
L
L
H
H
X
V
H
V
H
L
H
L
L
Active(4)
H
H
X
V
L
V
V
L
H
L
H
Read (BC4, on the fly)
Active(4)
H
H
X
V
L
V
L
L
H
L
H
Read (BL8, on the fly)
Active(4)
H
H
X
V
L
V
H
L
H
L
H
Active(4)
H
H
X
V
H
V
V
L
H
L
H
Active(4)
H
H
X
V
H
V
L
L
H
L
H
Active(4)
H
H
X
V
H
V
H
L
H
L
H
(Extended) Mode Register Set
Idle
H
H
X
V
L
L
L
L
No-Operation
Any
H
H
X
V
V
V
V
L
H
H
H
Device Deselect
Any
H
H
X
X
X
X
X
H
X
X
X
Refresh
Idle
H
H
X
V
V
V
V
L
L
L
H
SelfRefresh Entry
Idle
H
L
X
V
V
V
V
L
L
L
H
SelfRefresh Exit
Idle
L
H
X
X
X
X
X
H
X
X
X
V
V
V
V
L
H
H
H
Power Down Mode Entry
Idle
H
L
X
X
X
X
X
H
X
X
X
V
V
V
V
L
H
H
H
X
X
X
X
H
X
X
X
V
V
V
V
L
H
H
H
X
X
X
X
X
X
X
BankActivate
Write with Autoprecharge
(Fixed BL8 or BC4)
Write with Autoprecharge
(BC4, on the fly)
Write with Autoprecharge
(BL8, on the fly)
Read with Autoprecharge
(Fixed BL8 or BC4)
Read with Autoprecharge
(BC4, on the fly)
Read with Autoprecharge
(BL8, on the fly)
Row address
RAS# CAS#
OP code
Power Down Mode Exit
Any
L
H
X
Data Input Mask Disable
Active
H
X
L
X
Data Input Mask Enable(5)
Active
H
X
H
X
X
X
X
X
X
X
X
Idle
H
H
X
X
H
X
X
L
H
H
L
X
L
H
H
L
ZQ Calibration Long
Idle
H
H
X
X
L
X
NOTE 1: V=Valid data, X=Don't Care, L=Low level, H=High level
NOTE 2: CKEn signal is input level when commands are provided.
NOTE 3: CKEn-1 signal is input level one clock cycle before the commands are provided.
NOTE 4: These are states of bank designated by BA signal.
NOTE 5: DM can be enabled respectively.
ZQ Calibration Short
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Functional Description
The DDR3 SDRAM is a high-speed dynamic random access memory internally configured as an eight-bank DRAM.
The DDR3 SDRAM uses an 8n prefetch architecture to achieve high speed operation. The 8n Prefetch architecture
is combined with an interface designed to transfer two data words per clock cycle at the I/O pins. A single read or
write operation for the DDR3 SDRAM consists of a single 8n-bit wide, four clock 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 operation to the DDR3 SDRAM are burst oriented, start at a selected location, and continue for a
burst length of eight or a ‘chopped’ burst of four in a programmed sequence. Operation begins 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 activated (BA0-BA2 select the bank; A0-A14
select the row). The address bit registered coincident with the Read or Write command are used to select the
starting column location for the burst operation, determine if the auto precharge command is to be issued (via A10),
and select BC4 or BL8 mode ‘on the fly’ (via A12) if enabled in the mode register.
Prior to normal operation, the DDR3 SDRAM must be powered up and initialized in a predefined manner. The
following sections provide detailed information covering device reset and initialization, register definition, command
descriptions and device operation.
Figure 4. Reset and Initialization Sequence at Power-on Ramping
CK#
Ta
Tb
Tc
CK
VDD
VDDQ
Td
Te
Tf
Tg
Th
Ti
Tj
Tk
tCKSRX
T=200μs
T=500μs
RESET#
Tmin=10ns
tIS
CKE
tDLLK
tIS
COMMAND
Note 1
BA
tXPR
tMRD
tMRD
tMRD
tMOD
MRS
MRS
MRS
MRS
MR2
MR3
MR1
MR0
tZQinit
ZQCL
Note 1
VALID
tIS
ODT
VALID
tIS
Static LOW in case RTT_Nom is enabled at time Tg, otherwise static HIGH or LOW
VALID
RTT
NOTE 1. From time point “Td”until “Tk”NOP or DES commands must be applied between MRS and ZQCL commands.
TIME BREAK
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Power-up and Initialization
The Following sequence is required for POWER UP and Initialization.
1. Apply power (RESET# is recommended to be maintained below 0.2 x VDD, all other inputs may be undefined).
RESET# needs to be maintained for minimum 200us with stable power. CKE is pulled “Low” anytime before
RESET# being de-asserted (min. time 10ns). The power voltage ramp time between 300mV to VDDmin must be
no greater than 200ms; and during the ramp, VDD>VDDQ and (VDD-VDDQ)