Hyundai HPT-4205, Руководство по обслуживанию

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37
Plasma TV Service Manual 14/03/2005
12.29.2. Features
• PC66-, PC100-, and PC133-compliant
• Fully synchronous; all signals registered on positive edge of system clock
• Internal pipelined operation; column address can be changed every clock cycle
• Internal banks for hiding row access/precharge
• Programmable burst lengths: 1, 2, 4, 8, or full page
• Auto Precharge, includes CONCURRENT AUTO PRECHARGE, and Auto Refresh Modes
• Self Refresh Modes: standard and low power
• 64ms, 4,096-cycle refresh
• LVTTL-compatible inputs and outputs
• 3.3V ±0.3V power supply
12.29.3. Pin Descriptions
PIN NUMBERS SYMBOL TYPE DESCRIPTION
38 CLK Input Clock: CLK is driven by the system clock. All SDRAM input
signals are sampled on the positive edge of CLK. CLK also
increments the internal burst counter and controls the output
registers.
37 CKE Input Clock Enable: CKE activates (HIGH) and deactivates (LOW)
the CLK signal. Deactivating the clock provides PRECHARGE
POWER-DOWN and SELF REFRESH operation (all banks
idle), ACTIVE POWER-DOWN (row active in any bank) or
CLOCK SUSPEND operation (burst/access in progress). CKE
is synchronous except after the device enters power-down and
self refresh modes, where CKE becomes asynchronous until
after exiting the same mode. The input buffers, including CLK,
are disabled during power-down and self refresh modes,
providing low standby power. CKE may be tied HIGH.
19 CS# Input Chip Select: CS# enables (registered LOW) and disables
(registered 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.
16, 17, 18 WE#, CAS#,
RAS# Input Command Inputs: WE#, CAS#, and RAS# (along with CS#)
define the command being entered.
39 x4, x8: DQM
15, 39 x16: DQML,
DQMH
Input Input/Output Mask: DQM is an input mask signal for write
accesses and an output enable signal for read accesses. Input
data is masked when DQM is sampled HIGH during a WRITE
cycle. The output buffers are placed in a High-Z state (two-
clock latency) when DQM is sampled HIGH during a READ
cycle. On the x4 and x8, DQML (Pin 15) is a NC and DQMH is
DQM. On the x16, DQML corresponds to DQ0-DQ7 and
DQMH corresponds to DQ8-DQ15. DQML and DQMH are
considered same state when referenced as DQM.
20, 21 BA0, BA1 Input Bank Address Inputs: BA0 and BA1 define to which bank the
ACTIVE, READ, WRITE or PRECHARGE command is being
applied.
23-26, 29-34, 22,
35 A0-A11 Input Address Inputs: A0-A11 are sampled during the ACTIVE
command (row-address A0-A11) and READ/WRITE command
(column-address A0-A9 [x4]; A0-A8 [x8]; A0-A7 [x16]; with A10
defining auto precharge) to select one location out of the
memory array in the respective bank. A10 is sampled during a
PRECHARGE command to determine if all banks are to be
precharged (A10[HIGH]) or bank selected by BA0, BA1
(A1[LOW]). The address inputs also provide the op-code
during a LOAD MODE REGISTER command.
2, 4, 5, 7, 8, 10,
11, 13, 42, 44, 45,
47, 48, 50, 51, 53 DQ0-DQ15 x16: I/O Data Input/Output: Data bus for x16 (4, 7, 10, 13, 42, 45, 48,
and 51 are NCs for x8; and 2, 4, 7, 8, 10, 13, 42, 45, 47, 48,
51, and 53 are NCs for x4).
2, 5, 8, 11, 44, 47,
50, 53 DQ0-DQ7 x8: I/O Data Input/Output: Data bus for x8 (2, 8, 47, 53 are NCs for
x4).
5, 11, 44, 50 DQ0-DQ3 x4: I/O Data Input/Output: Data bus for x4.
40 NC – No Connect: These pins should be left unconnected.