K522H1HACF-B050 Datasheet, PDF (66/94 Pages) Samsung semiconductor – MCP Specification

K522H1HACF-B050
datasheet
Rev. 1.0
MCP Memory
3. ROW ACTIVE
The Bank Activation command is issued by holding CAS and WE high with CS and RAS low at the rising edge of the clock (CK). The Mobile DDR SDRAM
has four independent banks, so two Bank Select addresses(BA0, BA1) are required. The Bank Activation command must be applied before any Read or
Write operation is executed. The delay from the Bank Activation command to the first read or write command must meet or exceed the minimum of RAS
to CAS delay time, tRCD(min). Once a bank has been activated, it must be precharged before another Bank Activation command can be applied to the
same bank. The minimum time interval between interleaved Bank Activation commands (Bank A to Bank B and vice versa) is the Bank to Bank delay
time, tRRD(min).
Any system or application incorporating random access memory products should be properly designed, tested and qualifided to ensure proper use or
access of such memory products. Disproportionate, excessive and/or repeated access to a particular address or addresses may result in reduction of
product life.
0
CK
CK
Bank A
Address _{Row Addr.}
Command
Bank A
Activate
1
2
3
4
5
Tn
Tn+1
Tn+2
Bank A
Col. Addr.
RAS-CAS delay(tRCD)
NOP
NOP
Write A
with Auto
Precharge
NOP
NOP
Bank B
Row Addr.
Bank A
Row. Addr.
RAS-RAS delay time(tRRD)
Bank B
Activate
NOP
Bank A
Activate
ROW Cycle Time(tRC)
: Don′t care
Figure 1. Bank Activation Command Cycle timing <tRCD=3CLK, tRRD=2CLK>
4. READ BANK
This command is used after the row activate command to initiate the burst read of data. The read command is initiated by activating RAS, CS, CAS, and
WE at the same clock sampling (rising) edge as described in the command truth table. The length of the burst and the CAS latency time will be deter-
mined by the values programmed during the MRS cycle.
5. WRITE BANK
This command is used after the row activate command to initiate the burst write of data. The write command is initiated by activating RAS, CS, CAS, and
WE at the same clock sampling(rising) edge as described in the command truth table. The length of the burst will be determined by the values pro-
grammed during the MRS cycle.
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