HY[B/E]18L256160B[C/F]X-7.5
256-Mbit Mobile-RAM
Overview
1.4
Pin Definition and Description
Table 4
Ball
Pin Description
Type
Input
Input
Detailed Function
CLK
Clock: all inputs are sampled on the positive edge of CLK.
CKE
Clock Enable: CKE HIGH activates and CKE LOW deactivates internal clock signals,
device input buffers and output drivers. Taking CKE LOW provides PRECHARGE
POWER-DOWN and SELF REFRESH operation (all banks idle), ACTIVE POWER-
DOWN (row active in any bank) or SUSPEND (access in progress). Input buffers,
excluding CLK and CKE are disabled during power-down. Input buffers, excluding CKE
are disabled during SELF REFRESH.
CS
Input
Input
Chip Select: All commands are masked when CS is registered HIGH. CS provides for
external bank selection on systems with multiple memory banks. CS is considered part of
the command code.
RAS, CAS,
WE
Command Inputs: RAS, CAS and WE (along with CS) define the command being
entered.
DQ0 - DQ15 I/O
Data Inputs/Output: Bi-directional data bus (16 bit)
LDQM,
UDQM
Input
Input/Output Mask: input mask signal for WRITE cycles and output enable for READ
cycles. For WRITEs, DQM acts as a data mask when HIGH. For READs, DQM acts as
an output enable and places the output buffers in High-Z state when HIGH (two clocks
latency).
LDQM corresponds to the data on DQ0 - DQ7; UDQM to the data on DQ8 - DQ15.
BA0, BA1
A0 - A12
Input
Input
Bank Address Inputs: BA0 and BA1 define to which bank an ACTIVATE, READ, WRITE
or PRECHARGE command is being applied. BA0, BA1 also determine which mode
register is to be loaded during a MODE REGISTER SET command (MRS or EMRS).
Address Inputs: A0 - A12 define the row address during an ACTIVE command cycle. A0
- A8 define the column address during a READ or WRITE command cycle. In addition,
A10 (= AP) controls Auto Precharge operation at the end of the burst read or write cycle.
During a PRECHARGE command, A10 (= AP) in conjunction with BA0, BA1 controls
which bank(s) are to be precharged: if A10 is HIGH, all four banks will be precharged
regardless of the state of BA0 and BA1; if A10 is LOW, BA0, BA1 define the bank to be
precharged. During MODE REGISTER SET commands, the address inputs hold the op-
code to be loaded.
VDDQ
Supply I/O Power Supply: Isolated power for DQ output buffers for improved noise immunity:
DDQ = 1.70V to 1.95V
V
VSSQ
VDD
Supply I/O Ground
Supply Power Supply: Power for the core logic and input buffers, VDD = 1.70V to 1.95V
Supply Ground
VSS
N.C.
–
No Connect
Data Sheet
6
Rev. 1.11, 2007-01
07142005-CR47-RB2E
QIMONDA [ QIMONDA AG ]
