TI SMJ55166

SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
D
D
D
D
D
D
D
D
D
Organization:
– DRAM: 262 144 Words × 16 Bits
– SAM: 256 Words × 16 Bits
Dual-Port Accessibility – Simultaneous and
Asynchronous Access From the DRAM and
SAM Ports
Data-Transfer Function From the DRAM to
the Serial-Data Register
(4 × 4) × 4 Block-Write Feature for Fast
Area-Fill Operations; as Many as Four
Memory-Address Locations Written Per
Cycle From the 16-Bit On-Chip Color
Register
Write-Per-Bit Feature for Selective Write to
Each RAM I/O; Two Write-Per-Bit Modes to
Simplify System Design
Byte-Write Control (WEL, WEU) Provides
Flexibility
Extended Data Output (EDO) for Faster
System Cycle Time
Performance Ranges:
D
D
D
D
D
D
D
D
D
D
D
ACCESS TIME
ROW ENABLE
ta(R)
(MAX)
ACCESS TIME
SERIAL DATA
ta(SQ)
(MAX)
DRAM
CYCLE TIME
tc(W)
(MIN)
DRAM
PAGE MODE
tc(P)
(MIN)
75 ns
80 ns
23 ns
25 ns
140 ns
150 ns
48 ns
50 ns
SMJ55166-75
SMJ55166-80
Enhanced Page-Mode Operation for Faster
Access
CAS-Before-RAS (CBR) and
Hidden-Refresh Modes
Long Refresh Period
Every 8 ms (Max)
Up to 45-MHz Uninterrupted Serial-Data
Streams
256 Selectable Serial-Register Starting
Locations
SE-Controlled Register-Status QSF
Split-Register-Transfer Read for Simplified
Real-Time Register Load
Programmable Split-Register Stop Point
3-State Serial Outputs Allow Easy
Multiplexing of Video-Data Streams
All Inputs / Outputs and Clocks
TTL-Compatible
Compatible With JEDEC Standards
Designed to Work With the
Texas Instruments Graphics Family
SERIAL
OPERATING CURRENT
OPERATING CURRENT
CYCLE TIME SERIAL PORT STAND- SERIAL PORT
ACtc(SC)
ICC1
ICC1A
BY
TIVE
(MIN)
(MAX)
(MAX)
24 ns
30 ns
165 mA
160 mA
210 mA
195 mA
description
The SMJ55166 multiport video RAM is a high-speed, dual-ported memory device. It consists of a dynamic
random-access memory (DRAM) module organized as 262 144 words of 16 bits each that are interfaced to a
serial-data register (serial-access memory [SAM]) organized as 256 words of 16 bits each. The SMJ55166
supports three basic types of operation: random access to and from the DRAM, serial access from the serial
register, and transfer of data from any row in the DRAM to the serial register. Except during transfer operations,
the SMJ55166 can be accessed simultaneously and asynchronously from the DRAM and SAM ports.
The SMJ55166 is equipped with several features designed to provide higher system-level bandwidth and to
simplify design integration on both the DRAM and SAM ports. On the DRAM port, greater pixel draw rates are
achieved by the (4 × 4) × 4 block-write feature of the device. The block-write mode allows 16 bits of data (present
in an on-chip color-data register) to be written to any combination of four adjacent column-address locations.
As many as 64 bits of data can be written to memory during each CAS cycle time. Also on the DRAM port, a
write mask or a write-per-bit feature allows masking of any combination of the 16 inputs/outputs on any write
cycle. The persistent write-per-bit feature uses a mask register that, once loaded, can be used on subsequent
write cycles without reloading. The SMJ55166 also offers byte control, which can be applied in write cycles,
block-write cycles, load-write-mask-register cycles, and load-color-register cycles. The SMJ55166 also offers
extended-data-output (EDO) mode, which is effective in both the page-mode and standard DRAM cycles.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of
Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
Copyright  1997, Texas Instruments Incorporated
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of Texas Instruments
standard warranty. Production processing does not necessarily include
testing of all parameters.
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1
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
HKC PACKAGE
( TOP VIEW )
VCC
TRG
VSS
SQ0
DQ0
SQ1
DQ1
VCC
SQ2
DQ2
SQ3
DQ3
VSS
SQ4
DQ4
SQ5
DQ5
VCC
SQ6
DQ6
SQ7
DQ7
VSS
WEL
WEU
RAS
A8
A7
A6
A5
A4
VCC
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
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
33
SC
SE
VSS
SQ15
DQ15
SQ14
DQ14
VCC
SQ13
TERMINAL NOMENCLATURE
A0 – A8
CAS
DQ0 – DQ15
DSF
NC/VSS
DQ13
SQ12
DQ12
VSS
SQ11
DQ11
SQ10
DQ10
VCC
QSF
RAS
SC
SE
SQ0 – SQ15
TRG
VCC
VSS
WEL, WEU
SQ9
DQ9
SQ8
DQ8
VSS
DSF
NC / VSS
CAS
QSF
A0
A1
A2
A3
VSS
Address Inputs
Column-Address Strobe
DRAM-Data I/O, Write-Mask Data
Special-Function Select
No Connect / Ground (Important: Not
connected internally to VSS)
Special-Function Output
Row-Address Strobe
Serial Clock
Serial Enable
Serial-Data Output
Output Enable, Transfer Select
5-V Supply (TYP)
Ground
DRAM Byte-Write-Enable Selects
GB PACKAGE
( BOTTOM VIEW )
J
H
G
F
E
D
C
B
A
1
2
2
3
4
POST OFFICE BOX 1443
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• HOUSTON, TEXAS 77251–1443
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
GB Package Terminal Assignments — By Location
NO.
PIN
NAME
NO.
PIN
NAME
NO.
PIN
NAME
NO.
PIN
NAME
PIN
NAME
NO.
NO.
PIN
NAME
NO.
PIN
NAME
NO.
PIN
NAME
NO.
PIN
NAME
J1
DQ1
J2
SQ3
J3
DQ3
J4
DQ4
J5
DQ5
J6
DQ6
J7
SQ7
J8
WEL
J9
A8
H1
DQ0
H2
SQ2
H3
DQ2
H4
SQ4
H5
SQ5
H6
SQ6
H7
DQ7
H8
WEU
H9
A7
G1
SQ0
G2
SQ1
G3
VSS2
G6
VCC2
G7
RAS
G9
A6
F2
VSS1
VCC1
F3
VSS2
VCC1
G8
TRG
VCC2
VCC1
G4
F1
F8
F9
A5
E8
VCC1
VSS1
E9
A4
D3
VSS1
VSS2
D8
A3
D9
A2
C8
CAS
C9
A1
E1
SC
E2
D1
SE
D2
C1
SQ15
C2
VSS1
VSS1
B1
DQ15
B2
A1
SQ14
A2
F7
C3
VCC1
VCC2
D7
C4
DQ14
B3
DQ13
SQ13
A3
SQ12
B4
VSS2
DQ12
C6
B5
DQ11
A4
SQ11
A5
SQ10
C7
B6
VCC2
DQ10
B7
SQ8
B8
DSF
B9
A0
A6
SQ9
A7
DQ9
A8
DQ8
A9
QSF
GB Package Terminal Assignments — By Signals
PIN
PIN
PIN
PIN
PIN
PIN
NAME
NO.
NAME
NO.
NAME
NO.
NAME
NO.
NAME
NO.
NAME
NO.
A0
B9
DQ2
H3
DQ13
B3
SQ3
J2
SQ14
A1
C6
A1
C9
DQ3
J3
DQ14
B2
SQ4
H4
SQ15
C1
VCC2
VSS1
A2
D9
DQ4
J4
DQ15
B1
SQ5
H5
TRG
F1
D2
A3
D8
DQ5
J5
DSF
B8
SQ6
H6
E2
A4
E9
DQ6
J6
QSF
A9
SQ7
J7
VCC1
VCC1
VSS1
VSS1
F9
DQ7
H7
RAS
G8
SQ8
B7
D3
A6
G9
DQ8
A8
SC
E1
SQ9
A6
VCC1
VCC1
VSS1
VSS1
D7
A5
G4
A7
H9
DQ9
A7
SE
D1
SQ10
A5
VSS2
VSS2
A8
J9
DQ10
B6
SQ0
G1
SQ11
A4
G7
CAS
C8
DQ11
B5
SQ1
G2
SQ12
A3
DQ0
H1
DQ12
B4
SQ2
H2
SQ13
A2
DQ1
J1
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F3
F7
F8
F2
C2
E8
VCC1
VCC2
G3
VCC2
VCC2
C3
VSS2
VSS2
C4
G6
WEL
J8
WEU
H8
C7
3
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
description (continued)
The SMJ55166 offers a split-register-transfer read (DRAM to SAM) feature for the serial register (SAM port) that
enables real-time register-load implementation for truly continuous serial-data streams without critical timing
requirements. The register is divided into a high half and a low half. While one half is being read out of the SAM
port, the other half can be loaded from the memory array. For applications not requiring real-time register load
(for example, loads done during CRT-retrace periods), the full-register mode of operation is retained to simplify
system design.
The SAM port is designed for maximum performance, enabling data to be accessed from the SAM at serial rates
up to 45 MHz. During the split-register-transfer read operations, internal circuitry detects when the last bit
position is accessed from the active half of the register and immediately transfers control to the opposite half.
A separate output, QSF, is included to indicate which half of the serial register is active.
All inputs, outputs, and clock signals on the SMJ55166 are compatible with Series 54 TTL. All address lines and
data-in lines are latched on-chip to simplify system design. All data-out lines are unlatched to allow greater
system flexibility.
The SMJ55166 is offered in a 68-pin ceramic pin-grid-array package (GB suffix) and a 64-pin ceramic flatpack
(HKC suffix).
The SMJ55166 and other TI multiport video RAMs are supported by a broad line of graphics processors and
control devices from TI. Table 1 is a combination of Table 3 and Table 4, showing the DRAM and SAM functions
with the terminal signal levels. Table 2 shows the relationship between terminal descriptions and operational
modes.
4
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
functional block diagram
1 of 4 Subblocks
(see next page)
DSF
Input
Buffer
Input
Buffer
DQ0 –
DQ15
SpecialFunction
Logic
Column
Buffer
1 of 4 Subblocks
(see next page)
16
9
A0 – A8
Row
Buffer
Output
Buffer
SC
1 of 4 Subblocks
(see next page)
SQ0 – SQ15
16
SerialAddress
Counter
Refresh
Counter
SplitRegister
Status
SerialOutput
Buffer
QSF
SE
1 of 4 Subblocks
(see next page)
RAS
CAS
TRG
SE
Timing
Generator
WEx
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5
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
functional block diagram (continued)
DSF
Input
Buffer
SpecialFunction
Logic
Color
Register
DRAM
Input
Buffer
DQi
DQi+1
DQi+2
DQi+3
W/B
Unlatch
MUX
W/B
Latch
Address
Mask
WritePer-Bit
Control
DRAM
Output
Buffer
Column DEC
RAS
CAS
TRG
WEx
Column
Buffer
Sense AMP
Timing
Generator
512 × 512
Memory
Array
Row
Buffer
Row
Decoder
Serial-Data
Register
Serial-Data
Pointer
SQi
SQi+1
SQi+2
SQi+3
SC
SerialAddress
Counter
SerialOutput
Buffer
SE
1 of 4 Subblocks
Refresh
Counter
Split Register
Status
QSF
SE
6
9
A0 – A8
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
operation
Table 1. DRAM and SAM Function Table
CAS
FALL
RAS FALL
ADDRESS
DQ0 – DQ15 †
FUNCTION
MNE
CODE
CAS
TRG
WEx‡
DSF
DSF
RAS
CAS§
RAS
WEL
WEU
CAS
Reserved (do not use)
L
L
L
L
X
X
X
X
X
—
CBR refresh (no reset) and stop-point
set (CBRS) ¶
L
X
L
H
X
Stop
Point #
X
X
X
CBRS
CBR refresh (option reset)||
L
X
H
L
X
X
X
X
X
CBR
CBR refresh (no reset)k
L
X
H
H
X
X
X
X
X
CBRN
Full-register-transfer read
H
L
H
L
X
Row
Address
Tap
Point
X
X
RT
Split-register-transfer read
H
L
H
H
X
Row
Address
Tap
Point
X
X
SRT
DRAM write
(nonpersistent write-per-bit)
H
H
L
L
L
Row
Address
Column
Address
Write
Mask
Valid
Data
RWM
DRAM block write
(nonpersistent write-per-bit)
H
H
L
L
H
Row
Address
Block
Address
A2 – A8
Write
Mask
Column
Mask
BWM
DRAM write
(persistent write-per-bit)
H
H
L
L
L
Row
Address
Column
Address
X
Valid
Data
RWM
DRAM block write
(persistent write-per-bit)
H
H
L
L
H
Row
Address
Block
Address
A2 – A8
X
Column
Mask
BWM
DRAM write (nonmasked)
H
H
H
L
L
Row
Address
Column
Address
X
Valid
Data
RW
DRAM block write (nonmasked)
H
H
H
L
H
Row
Address
Block
Address
A2 – A8
X
Column
Mask
BW
Load write-mask register h
H
H
H
H
L
Refresh
Address
X
X
Write
Mask
LMR
Load color register
H
H
H
H
H
Refresh
Address
X
X
Color
Data
LCR
Legend:
Col Mask
= H: Write to address/column enabled
Write Mask = H: Write to I/O enabled
X
= Don’t care
† DQ0 – DQ15 are latched on either the first falling edge of WEx or the falling edge of CAS, whichever occurs later.
‡ Logic L is selected when either or both WEL and WEU are low.
§ The column address and block address are latched on the first falling edge of CAS.
¶ CBRS cycle should be performed immediately after the power-up initialization cycle.
# A0 – A3, A8: don’t care; A4 – A7 : stop-point code
|| CBR refresh (option reset) mode ends persistent write-per-bit mode and stop-point mode.
k CBR refresh (no reset) mode does not end persistent write-per-bit mode or stop-point mode.
h Load write-mask-register cycle sets the persistent write-per-bit mode. The persistent write-per-bit mode is reset only by the CBR (option reset)
cycle.
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
operation (continued)
Table 2. Terminal Description Versus Operational Mode
PIN
DRAM
TRANSFER
A0 – A8
Row, column address
Row address, tap point
CAS
Column-address strobe, DQ output enable
Tap-address strobe
DQ
DRAM data I/O, write mask
DSF
Block-write enable
Write-mask-register load enable
Color-register load enable
CBR (option reset)
Split-register-transfer enable
RAS
Row-address strobe
Row-address strobe
SAM
SE
SQ output enable,
QSF output enable
SC
Serial clock
SQ
Serial-data output
TRG
DQ output enable
WEL
WEU
Write enable, write-per-bit enable
Transfer enable
QSF
NC/VSS
VCC†
Serial-register status
Either make no external connection or tie to system VSS
5-V supply
VSS†
Ground
† For proper device operation, all VCC pins must be connected to a 5-V supply and all VSS pins must be tied to ground.
terminal definitions
address (A0 –A8)
Eighteen address bits are required to decode each of the 262 144 storage cell locations. Nine row-address bits
are set up on pins A0 – A8 and latched onto the chip on the falling edge of RAS. Nine column-address bits are
set up on pins A0 – A8 and latched onto the chip on the falling edge of CAS. All addresses must be stable on
or before the falling edge of RAS and the falling edge of CAS.
During the full-register-transfer read operation, the states of A0 –A8 are latched on the falling edge of RAS to
select one of the 512 rows where the transfer occurs. At the falling edge of CAS, the column-address bits A0 – A8
are latched. The most significant column-address bit (A8) selects which half of the row is transferred to the SAM.
The appropriate 8-bit column address (A0 – A7) selects one of 256 tap points (starting positions) for the
serial-data output.
During the split-register-transfer read operation, address bit A7 is ignored at the falling edge of CAS. An internal
counter selects which half of the register is used. If the high half of the SAM is currently in use, the low half of
the SAM is loaded with the low half of the DRAM half row and vice versa. Column address (A8) selects the DRAM
half row. The remaining seven address bits (A0 – A6) are used to select each of the 127 possible starting
locations within the SAM. Locations 127 and 255 are not valid tap points.
row-address strobe (RAS)
RAS is similar to a chip enable so that all DRAM cycles and transfer cycles are initiated by the falling edge of
RAS. RAS is a control input that latches the states of the row address, WEL, WEU, TRG, CAS, and DSF onto
the chip to invoke DRAM and transfer functions of the SMJ55166.
8
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
column-address strobe (CAS)
CAS is a control input that latches the states of the column address and DSF to control DRAM and transfer
functions of the SMJ55166. CAS also acts as output enable for the DRAM output pins DQ0 – DQ15. During
transfer operations, address bits A0 – A8 are latched at the falling edge of CAS as the start position (tap) for the
serial-data output (SQ0 – SQ15).
output enable/transfer select (TRG)
TRG selects either DRAM or transfer operation as RAS falls. For DRAM operation, TRG must be held high as
RAS falls. During DRAM operation, TRG functions as an output enable for the DRAM output pins DQ0 – DQ15.
For transfer operation, TRG must be brought low before RAS falls.
write-mask select, write enable (WEL, WEU)
In DRAM operation, WEL enables data to be written to the lower byte (DQ0 – DQ7) and WEU enables data to
be written to the upper byte (DQ8 – DQ15) of the DRAM. Both WEL and WEU have to be held high together to
select the read mode. Bringing either or both WEL and WEU low selects the write mode. WEL and WEU are
also used to select the DRAM write-per-bit mode. Holding either or both WEL and WEU low on the falling edge
of RAS invokes the write-per-bit operation. The SMJ55166 supports both the nonpersistent write-per-bit mode
and the persistent write-per-bit mode.
special-function select (DSF)
The DSF input is latched on the falling edge of RAS or the first falling edge of CAS, similar to an address. DSF
determines which of the following functions is invoked on a particular cycle:
D
D
D
D
D
D
D
CBR refresh with reset (CBR)
CBR refresh with no reset (CBRN)
CBR refresh with no reset and stop-point set (CBRS)
Block write (BW)
Load write-mask register (LMR) loading for the persistent write-per-bit mode
Load color register (LCR) for the block-write mode
Split-register-transfer (SRT) read
DRAM-data I/O, write-mask data (DQ0 – DQ15)
DRAM data is written or read through the common I/O DQ pins. The 3-state DQ-output buffers provide direct
TTL compatibility (no pul lup resistors) with a fanout of one Series 54 TTL load. Data out is the same polarity
as data in. The outputs are in the high-impedance (floating) state as long as either TRG or CAS is held high.
Data does not appear at the outputs until after both CAS and TRG have been brought low. The write mask is
latched into the device through the random DQ pins by the falling edge of RAS and is used on all write-per-bit
cycles. In a transfer operation, the DQ outputs remain in the high-impedance state for the entire cycle.
serial-data outputs (SQ0 – SQ15)
Serial data is read from SQ. SQ output buffers provide direct TTL compatibility (no pullup resistors) with a fanout
of one Series 54 TTL load. The serial outputs are in the high-impedance (floating) state while the serial-enable
pin, SE, is high. The serial outputs are enabled when SE is brought low.
serial clock (SC)
Serial data is accessed out of the data register from the rising edge of SC. The SMJ55166 is designed to work
with a wide range of clock duty cycles to simplify system design. There is no refresh requirement because the
data registers that comprise the SAM are static. There is also no minimum SC clock operating frequency.
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9
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
serial enable (SE)
During serial-access operations, SE enables/disables the SQ outputs. SE low enables the serial-data output
while SE high disables the serial-data output. SE is also used as an enable/disable for output pin QSF.
NOTE:While SE is held high, the serial clock is not disabled. External SC pulses increment the
internal serial-address counter, regardless of the state of SE. This ungated serial-clock scheme
minimizes access time of serial output from SE low because the serial-clock input buffer and the
serial-address counter are not disabled by SE.
special-function output (QSF)
QSF is an output pin that indicates which half of the SAM is being accessed. When QSF is low, the serial-address
pointer accesses the lower (least significant) 128 bits of the SAM. When QSF is high, the pointer accesses the
higher (most significant) 128 bits of the SAM. QSF changes state upon crossing a boundary between the two
SAM halves.
During full-register-transfer operations, QSF can change state upon completing the cycle. This state is
determined by the tap point loaded during the transfer cycle. QSF output is enabled by SE. If SE is high, the
QSF output is in the high-impedance state.
no connect/ground (NC/VSS)
NC/VSS must be tied to system ground or left floating for proper device operation.
10
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
functional operation description
Table 3. DRAM Function Table
CAS
FALL
RAS FALL
ADDRESS
DQ0 – DQ15†
FUNCTION
MNE
CODE
CAS
TRG
WEx‡
DSF
DSF
RAS
CAS§
RAS
WEL
WEU
CAS
Reserved (do not use)
L
L
L
L
X
X
X
X
X
—
CBR refresh (no reset) and stop-point
set (CBRS)¶
L
X
L
H
X
Stop
Point #
X
X
X
CBRS
CBR refresh (option reset)||
L
X
H
L
X
X
X
X
X
CBR
CBR refresh (no reset)k
L
X
H
H
X
X
X
X
X
CBRN
DRAM write
(nonpersistent write-per-bit)
H
H
L
L
L
Row
Address
Column
Address
Write
Mask
Valid
Data
RWM
DRAM block write
(nonpersistent write-per-bit)
H
H
L
L
H
Row
Address
Block
Address
A2 – A8
Write
Mask
Column
Mask
BWM
DRAM write
(persistent write-per-bit)
H
H
L
L
L
Row
Address
Column
Address
X
Valid
Data
RWM
DRAM block write
(persistent write-per-bit)
H
H
L
L
H
Row
Address
Block
Address
A2 – A8
X
Column
Mask
BWM
DRAM write (nonmasked)
H
H
H
L
L
Row
Address
Column
Address
X
Valid
Data
RW
DRAM block write (nonmasked)
H
H
H
L
H
Row
Address
Block
Address
A2 – A8
X
Column
Mask
BW
Load write-mask register h
H
H
H
H
L
Refresh
Address
X
X
Write
Mask
LMR
Load color register
H
H
H
H
H
Refresh
Address
X
X
Color
Data
LCR
Legend:
Col Mask
= H: Write to address/column enabled
Write Mask = H: Write to I/O enabled
X
= Don’t care
† DQ0 – DQ15 are latched on either the first falling edge of WEx or the falling edge of CAS, whichever occurs later.
‡ Logic L is selected when either or both WEL and WEU are low.
§ The column address and block address are latched on the first falling edge of CAS.
¶ CBRS cycle should be performed immediately after the power-up initialization cycle.
# A0 – A3, A8: don’t care; A4 – A7 : stop-point code
|| CBR refresh (option reset) mode ends persistent write-per-bit mode and stop-point mode.
k CBR refresh (no reset) mode does not end persistent write-per-bit mode or stop-point mode.
h Load-write-mask-register cycle sets the persistent write-per-bit mode. The persistent write-per-bit mode is reset only by the CBR (option reset)
cycle.
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enhanced page mode
Enhanced page-mode operation allows faster memory access by keeping the same row address while selecting
random column addresses. This mode eliminates the time required for row-address setup, row-address hold,
and address multiplex. The maximum RAS low time and CAS-page-cycle time used determine the number of
columns that can be accessed.
Unlike conventional page-mode operations, the enhanced page mode allows the SMJ55166 to operate at a
higher data bandwidth. Data retrieval begins as soon as the column address is valid rather than when CAS
transitions low. A valid column address can be presented immediately after the row-address hold time has been
satisfied, usually well in advance of the falling edge of CAS. In this case, data is obtained after ta(C) max (access
time from CAS low) if ta(CA) max (access time from column address) has been satisfied.
refresh
CAS-before-RAS (CBR) refresh
CBR refreshes are accomplished by bringing CAS low earlier than RAS. The external row address is ignored
and the refresh row address is generated internally. Three types of CBR refresh cycles are available: the CBR
refresh (option reset) which ends the persistent write-per-bit mode and the stop-point mode and the CBRN
refresh and CBRS refresh (no reset), which do not end the persistent write-per-bit mode or the stop-point mode.
The 512 rows of the DRAM do not necessarily need to be refreshed consecutively as long as the entire refresh
is completed within the required time period, trf(MA). The output buffers remain in the high-impedance state
during the CBR refresh cycles regardless of the state of TRG.
hidden refresh
A hidden refresh is accomplished by holding CAS low in the DRAM read cycle and cycling RAS. The output data
of the DRAM read cycle remains valid while the refresh is carried out. Like the CBR refresh, the refreshed row
addresses are generated internally during the hidden refresh.
RAS-only refresh
A RAS-only refresh is accomplished by cycling RAS at every row address. Unless CAS and TRG are low, the
output buffers remain in the high-impedance state to conserve power. Externally generated addresses must be
supplied during RAS-only refresh. Strobing each of the 512 row addresses with RAS causes all bits in each row
to be refreshed.
extended data output
The SMJ55166 features extended-data output during DRAM accesses. While RAS and TRG are low, the DRAM
output remains valid. The output remains valid even when CAS returns high (until WEx is low), TRG is high,
or both CAS and RAS are high (see Figure 1 and Figure 2). The extended-data-output mode functions in all read
cycles including DRAM read, page-mode read, and read-modify-write cycles (see Figure 3).
RAS
CAS
tdis(RH)
Valid Output
DQ0 – DQ15
tdis(G)
TRG
Figure 1. DRAM Read Cycle With RAS-Controlled Output
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extended data output (continued)
RAS
CAS
tdis(CH)
DQ0 – DQ15
Valid Output
tdis(G)
TRG
Figure 2. DRAM Read Cycle With CAS-Controlled Output
RAS
CAS
A0 – A8
Row
Column
Column
ta(CP)
ta(C)
ta(CA)
ta(C)
ta(CA)
th(CLQ)
Valid Output
DQ0 – DQ15
Valid Output
TRG
Figure 3. DRAM Page-Read Cycle With Extended Output
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byte-write operation
Byte-write operations can be applied in DRAM-write cycles, block-write cycles, load-write-mask-register cycles,
and load-color-register cycles. Holding either or both WEL and WEU low selects the write mode. In normal write
cycles, WEL enables data to be written to the lower byte (DQ0 – DQ7) and WEU enables data to be written to
the upper byte (DQ8 – DQ15). For early-write cycles, one WEx is brought low before CAS falls. The other WEx
can be brought low before CAS falls or after CAS falls. The data is strobed in with data setup and hold times
for DQ0 – DQ15 referenced to CAS (see Figure 4).
RAS
CAS
WEL †
WEU
tsu(DCL)
th(CLD)
Valid Input
DQ0 – DQ15
† Either WEU or WEL can be brought low prior to CAS to initiate an early-write cycle.
Figure 4. Example of an Early-Write Cycle
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byte-write operation (continued)
For late-write or read-modify-write cycles, WEL and WEU are both held high before CAS falls. After CAS falls,
either or both WEL and WEU are brought low to select the corresponding byte or bytes to be written. Data is
strobed in by either or both WEL and WEU with data setup and hold times for DQ0 – DQ15 referenced to
whichever WEx falls earlier (see Figure 5).
RAS
CAS
WEL
WEU
tsu(DWL)
th(WLD)
Valid Input
DQ0 – DQ15
Figure 5. Example of a Late-Write Cycle
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write-per-bit
The write-per-bit feature allows masking any combination of the 16 DQs on any write cycle. The write-per-bit
operation is invoked when either WEL or WEU is held low on the falling edge of RAS. Assertion of either
individual WEx allows entry of the entire 16-bit mask on DQ0 – DQ15. Byte control of the mask input is not
allowed. If both WEL and WEU are held high on the falling edge of RAS, the write operation is performed without
any masking. The SMJ55166 offers two write-per-bit modes: nonpersistent write-per-bit and persistent
write-per-bit.
nonpersistent write-per-bit
When either or both WEL and WEU are low on the falling edge of RAS, the write mask is reloaded. A 16-bit binary
code (the write-per-bit mask) is input to the device through the random DQ pins and latched on the falling edge
of RAS. The write-per-bit mask selects which of the 16 random I/Os are to be written and which are not. After
RAS has latched the on-chip write-per-bit mask, input data is driven onto the DQ pins and is latched on either
the first falling edge of WEx or the falling edge of CAS, whichever occurs later. WEL enables the lower byte
(DQ0 – DQ7) to be written through the mask and WEU enables the upper byte (DQ8 – DQ15) to be written
through the mask. If a data low (write mask = 0) is strobed into a particular I/O pin on the falling edge of RAS,
data is not written to that I/O. If a data high (write mask = 1) is strobed into a particular I/O pin on the falling edge
of RAS, data is written to that I/O (see Figure 6).
RAS
CAS
WEL
WEU
tsu(DQR)
th(RDQ)
tsu(DWL)
th(WLD)
DQ0 – DQ15
Write Mask
Write Input
Figure 6. Example of a Nonpersistent Write-Per-Bit (Late-Write) Operation
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persistent write-per-bit
The persistent write-per-bit mode is initiated by performing a load-write-mask-register (LMR) cycle. In the
persistent write-per-bit mode, the write-per-bit mask is not overwritten but remains valid over an arbitrary
number of write cycles until another LMR cycle is performed or power is removed.
The LMR cycle is performed using DRAM write-cycle timing with DSF held high on the falling edge of RAS and
held low on the falling edge of CAS. A binary code is input to the write-mask register via the random I/O pins
and latched on either the first WEx falling edge or the falling edge of CAS, whichever occurs later. Byte write
control can be applied to the write mask during the LMR cycle. The persistent write-per-bit mode can then be
used in exactly the same way as the nonpersistent write-per-bit mode except that the input data on the falling
edge of RAS is ignored. When the device is set to the persistent write-per-bit mode, it remains in this mode and
is reset only by a CBR refresh ( option reset ) cycle (see Figure 7).
Load Write-Mask Register
Persistent Write-Per-Bit
CBR Refresh (option reset)
RAS
CAS
A0 – A8
Refresh
Address
Row
Column
DSF
WEx
DQ0 –
DQ15
Write-Mask
Data
Mask Data
Valid
Input
= . . . . . . 1 : Write to I/O enabled
=
0 : Write to I/O disabled
Figure 7. Example of a Persistent Write-Per-Bit Operation
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block write
The block-write feature allows up to 64 bits of data to be written simultaneously to one row of the memory array.
This function is implemented as 4 columns × 4 DQs and repeated in four quadrants. In this manner, each of the
four 1M-bit quadrants can have up to four consecutive columns written at a time with up to four DQs per column
(see Figure 8).
DQ15
DQ14
4th Quadrant
DQ13
DQ12
DQ11
DQ10
3rd Quadrant
DQ9
DQ8
One Row of 0 – 511
DQ7
DQ6
2nd Quadrant
DQ5
DQ4
DQ3
DQ2
1st Quadrant
DQ1
DQ0
4 Consecutive Columns of 0 – 511
Figure 8. Block-Write Operation
Each 1M-bit quadrant has a 4-bit column mask to mask off and prevent any or all of the four columns from being
written with data. Nonpersistent write-per-bit or persistent write-per-bit functions can be applied to the
block-write operation to provide write-masking options. The DQ data is provided by four bits from the on-chip
color register. Bits 0 – 3 from the 16-bit write-mask register, bits 0 – 3 from the 16-bit column-mask register, and
bits 0 – 3 from the 16-bit color-data register configure the block write for the first quadrant, while bits 4 – 7, 8 – 11,
and 12 – 15 of the corresponding registers control the other quadrants in a similar fashion (see Figure 9).
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block write (continued)
DQ15
DQ14
DQ13
DQ12
DQ11
DQ10
12
13
14
15
DQ9
DQ8
One Row of 0 – 511
DQ7
DQ6
8
9
10
11
DQ5
DQ4
DQ3
DQ2
4
5
6
7
DQ1
Column Mask
DQ0
0
1
2
3
3
7
Write Mask
1
5
1
2
3
4
5
15
14
9
8
4
0
0
11
10
6
2
6
7
8
13
12
9 10 11
12 13 14 15
Color Register
Figure 9. Block Write With Masks
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block write (continued)
Every four columns make a block, which results in 128 blocks along one row. Block 0 comprises columns 0 – 3,
block 1 comprises columns 4 – 7, block 2 comprises columns 8 – 11, and so forth, as shown in Figure 10.
Block 0
......................
Block 1
Block 127
One Row of 0 – 511
0
1
2
3
4
5
6
7
...........................
511
Columns
Figure 10. Block Columns Organization
During block-write cycles, only the seven most significant column addresses (A2 – A8) are latched on the falling
edge of CAS to decode one of the 128 blocks. Address bits A0 – A1 are ignored. Each 1M-bit quadrant has the
same block selected.
A block-write cycle is entered in a manner similar to a DRAM-write cycle except DSF is held high on the first
falling edge of CAS. As in a DRAM-write operation, WEL enables writing of the lower DRAM DQ byte while WEH
enables the upper byte. The column-mask data is input via the DQs and is latched on either the first falling edge
of WEx or the falling edge of CAS, whichever occurs later. The 16-bit color-data register must be loaded prior
to performing a block write as described below. Refer to the write-per-bit section for details on use of the
write-mask capability, allowing additional performance options.
Example of block write:
block-write column address
color-data register
write-mask register
column-mask register
= 110000000 (A0 – A8 from left to right)
bit 0
= 1011
= 1110
= 1111
1st
Quad
1011
1111
0000
2nd
Quad
1100
1111
0111
3rd
Quad
bit 15
0111
1011
1010
4th
Quad
Column-address bits A0 and A1 are ignored. Block 0 (columns 0 – 3) is selected for each 1M-bit quadrant. The
first quadrant has DQ0 – DQ2 written with bits 0 – 2 from the color-data register (101 ) to all four columns of block
0. DQ3 is not written and retains its previous data due to write-mask-register-bit 3 being a 0.
The second quadrant (DQ4 – DQ7) has all four columns masked off due to the column-mask bits 4 – 7 being 0,
so that no data is written.
The third quadrant (DQ8 – DQ11 ) has its four DQs written with bits 8 – 11 from the color-data register (1100) to
columns 1 – 3 of its block 0. Column 0 is not written and retains its previous data on all four DQs due to
column-mask-register-bit 8 being 0.
The fourth quadrant (DQ12 – DQ15) has DQ12, DQ14, and DQ15 written with bits 12, 14, and 15 from the
color-data register to column 0 and column 2 of its block 0. DQ13 retains its previous data on all columns due
to the write mask. Columns 1 and 3 retain their previous data on all DQs due to the column mask. If the previous
data for the quadrant was all 0s, the fourth quadrant would contain the data pattern shown in Figure 11 after
the block-write operation shown in the previous example.
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block write (continued)
DQ15 1
DQ14 1
0
0
1
1
0
0
4th Quadrant
DQ13 0
0
DQ12 0
0
0
0
Columns 0
1
2
3
0
0
Figure 11. Example of Fourth Quadrant After Block-Write Operation
load color register
The load-color-register cycle is performed using normal DRAM-write-cycle timing except that DSF is held high
on the falling edges of RAS and CAS. The color register is loaded from pins DQ0 – DQ15, which are latched
on either the first falling edge of WEx or the falling edge of CAS, whichever occurs later. If only one WEx is low,
only the corresponding byte of the color register is loaded. When the color register is loaded, it retains data until
power is lost or until another load-color-register cycle is performed (see Figure 12 and Figure 13 ).
Load-Color-Register Cycle
Block-Write Cycle
(no write mask)
Block-Write Cycle
(load and use write mask)
RAS
CAS
A0 – A8
1
2
3
2
3
WEx
TRG
DSF
DQ0 – DQ15
6
4
5
6
Legend:
1.
2.
3.
4.
5.
6.
Refresh address
Row address
Block address (A2 – A8) is latched on the falling edge of CAS.
Color-register data
Write-mask data: DQ0 – DQ15 are latched on the falling edge of RAS.
Column-mask data: DQi – DQi + 3 (i = 0, 4, 8, 12) are latched on either the first falling edge of WEx or the falling edge of CAS, whichever
occurs later.
= don’t care
Figure 12. Example of Block Writes
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load color register (continued)
Load-Mask-Register Cycle
Persistent Block-Write Cycle
(use loaded write mask)
Load-Color-Register Cycle
RAS
CAS
A0 – A8
1
2
1
3
WEx
TRG
DSF
DQ0 – DQ15
5
6
4
Legend:
1.
2.
3.
4.
5.
6.
Refresh address
Row address
Block address (A2 – A8) is latched on the falling edge of CAS.
Color-register data
Write-mask data: DQ0 – DQ15 are latched on the falling edge of CAS.
Column-mask data: DQi – DQi + 3 (i = 0, 4, 8, 12) are latched on either the first WEx falling edge or the falling edge of CAS, whichever
occurs later.
= don’t care
Figure 13. Example of a Persistent Block Write
DRAM-to-SAM transfer operation
During the DRAM-to-SAM transfer operation, one half of a row (256 columns) in the DRAM array is selected
to be transferred to the 256-bit serial-data register. The transfer operation is invoked by bringing TRG low and
holding WEx high on the falling edge of RAS. The state of DSF, which is latched on the falling edge of RAS,
determines whether the full-register-transfer read operation or the split-register-transfer read operation is
performed.
Table 4. SAM Function Table
CAS
FALL
RAS FALL
FUNCTION
ADDRESS
DQ0 – DQ15
MNE
CODE
CAS
TRG
WEx†
DSF
DSF
RAS
CAS
RAS
CAS
WEx
Full-register-transfer read
H
L
H
L
X
Row
Addr
Tap
Point
X
X
RT
Split-register-transfer read
H
L
H
H
X
Row
Addr
Tap
Point
X
X
SRT
† Logic L is selected when either or both WEL and WEU are low.
X = don’t care
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full-register-transfer read
A full-register-transfer read operation loads data from a selected half of a row in the DRAM into the serial-access
memory register (SAM). TRG is brought low and latched at the falling edge of RAS. Nine row-address bits
(A0 – A8) are also latched at the falling edge of RAS to select one of the 512 rows available for the transfer. The
nine column-address bits (A0 – A8) are latched at the falling edge of CAS, where address bit A8 selects which
half of the row is transferred. Address bits A0 – A7 select each of the 256 available tap points (of the SAM
register) from which the serial data is read (see Figure 14).
A8 = 0
0
255 256
A8 = 1
511
512 × 512
Memory Array
256-Bit
Data Register
0
255
Figure 14. Full-Register-Transfer Read
A full-register-transfer read can be performed in three ways: early load, real-time load (or midline load), or late
load. Each of these offers the flexibility of controlling the TRG trailing edge in the full-register-transfer read cycle
(see Figure 15).
Early Load
Real-Time Load
Late Load
RAS
CAS
A0 – A8
Row
Tap
Point
Row
Tap
Point
Row
Tap
Point
TRG
WEx
SC
Old
Data
Tap
Bit
Old
Data
Old
Data
Tap
Bit
Old
Data
Old
Data
Tap
Bit
Figure 15. Example of Full-Register-Transfer Read Operations
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split-register-transfer read
In the split-register-transfer read operation, the serial-data register is split into halves (see Figure 16). The low
half contains bits 0 – 127, and the high half contains bits 128 – 255. While one half is being read out of the SAM
port, the other half can be loaded from the memory array.
A8 = 0
0
255 256
A8 = 1
511
512 × 512
Memory Array
256 - Bit
Data Register
0
255
Figure 16. Split-Register-Transfer Read
To invoke a split-register-transfer read cycle, DSF is brought high, TRG is brought low, and both are latched at
the falling edge of RAS. Nine row-address bits (A0 – A8) are also latched at the falling edge of RAS to select
one of the 512 rows available for the transfer. Eight of the nine column-address bits (A0 – A6 and A8) are latched
at the falling edge of CAS. Column-address bit A8 selects which half of the row is to be transferred.
Column-address bits A0 – A6 select each of the 127 tap points in the specified half of the SAM. Column-address
bit A7 is ignored, and the split-register-transfer is internally controlled to select the inactive register half
(see Figure 17).
Full XFER
RAS
Split XFER
Split XFER
A8 = 1
A8 = 1
A8 = 0
0
511
A
A7 = 0† 511
0
A
B
B
C
Split XFER
A8 = 0
A7 = 1† 511
0
A
B
C
0 A7 = 0†
D
A
C
E
D
D
E
DRAM
0
SAM
511
B
0
255
A
255
C
B
SQ
† A7 shown as internally controlled.
0
B
255
C
0
D
SQ
SQ
255
SQ
Figure 17. Example of a Split-Register-Transfer Read Operation
A full-register-transfer read must precede the first split-register-transfer read to ensure proper operation. After
the full-register-transfer read cycle, the first split-register-transfer read can follow immediately without any
minimum SC clock requirement.
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split-register-transfer read (continued)
QSF indicates which half of the register is being accessed during serial-access operation. When QSF is low,
the serial-address pointer is accessing the lower (least significant) 128 bits of the SAM. When QSF is high, the
pointer is accessing the higher (most significant) 128 bits of the SAM. QSF changes state upon completing a
full-register-transfer read cycle. The tap point loaded during the current transfer cycle determines the state of
QSF. QSF also changes state when a boundary between two register halves is reached (see Figure 18 and
Figure 19).
Full-Register-Transfer Read
With Tap Point N
Split-RegisterTransfer Read
RAS
CAS
TRG
DSF
SC
Tap
Point N
td(CLQSF)
td(GHQSF)
QSF
Figure 18. Example of a Split-Register-Transfer Read After a Full-Register-Transfer Read
Split-RegisterTransfer Read
With Tap Point N
Split-RegisterTransfer Read
RAS
CAS
TRG
DSF
td(MSRL)
td(RHMS)
SC
127
or 255
Tap
Point N
td(SCQSF)
QSF
Figure 19. Example of Successive Split-Register-Transfer Read Operations
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serial-read operation
The serial-read operation can be performed through the SAM port simultaneously and asynchronously with
DRAM operations except during transfer operations. Serial data can be read from the SAM by clocking SC
starting at the tap point loaded by the preceding transfer cycle, proceeding sequentially to the most significant
bit (bit 255), and then wrapping around to the least significant bit (bit 0), as shown in Figure 20.
0
1
2
Tap
254
255
Figure 20. Serial-Pointer Direction for Serial Read
For split-register-transfer read operation, serial data can be read out from the active half of the SAM by clocking
SC starting at the tap point loaded by the preceding split-register-transfer cycle. The serial pointer then proceeds
sequentially to the most significant bit of the half, bit 127 or bit 255. If there is a split-register-transfer read to
the inactive half during this period, the serial pointer points next to the tap point location loaded by that
split-register-transfer (see Figure 21).
0
Tap
126
127
128
Tap
254
255
Figure 21. Serial Pointer for Split-Register-Transfer Read – Case I
If there is no split-register-transfer read to the inactive half during this period, the serial pointer points next to
bit 128 or bit 0, respectively (see Figure 22).
0
Tap
126
127
128
Tap
254
255
Figure 22. Serial Pointer for Split-Register-Transfer Read – Case II
split-register programmable stop point
The SMJ55166 offers programmable stop-point mode for split-register-transfer read operation. This mode can
be used to improve two-dimensional drawing performance in a nonscanline data format.
In split-register-transfer read operation, the stop point is defined as a register location at which the serial output
stops coming from one half of the SAM and switches to the opposite half of the SAM. While in stop-point mode,
the SAM is divided into partitions whose lengths are programmed via row addresses A4 – A7 in a CBR set
(CBRS) cycle. The last serial-address location of each partition is the stop point (see Figure 23).
127
0
128
255
Partition
Length
Stop
Points
Figure 23. Example of the SAM With Partitions
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MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
split-register programmable stop point (continued)
Stop-point mode is not active until the CBRS cycle is initiated. The CBRS operation is enabled by holding CAS
and WEx low and DSF high on the falling edge of RAS. The falling edge of RAS also latches row addresses
A4– A7, which are used to define the SAM partition length. The other row-address inputs are don’t cares.
Stop-point mode should be initiated after the initialization cycles are performed (see Table 5).
Table 5. Programming Code for Stop-Point Mode
MAXIMUM
PARTITION
LENGTH
A8
A7
A6
A5
A4
A0 – A3
NUMBER OF
PARTITIONS
16
X
L
L
L
L
X
16
15, 31, 47, 63, 79, 95, 111, 127, 143, 159, 175,
191, 207, 223, 239, 255
32
X
L
L
L
H
X
8
31, 63, 95, 127, 159, 191, 223, 255
64
X
L
L
H
H
X
4
63, 127, 191, 255
128
(default)
X
L
H
H
H
X
2
127, 255
ADDRESS AT RAS IN CBRS CYCLE
STOP POINT LOCATIONS
STOP-POINT
In stop-point mode, the tap point loaded during the split-register-transfer read cycle determines the SAM
partition in which the serial output begins, and also determines at which stop point the serial output stops coming
from one half of the SAM and switches to the opposite half of the SAM (see Figure 24).
RAS
Full
Read XFER
Split
Read XFER
Tap = H1
Split
Read XFER
Tap = L1
H1
Split
Read XFER
Tap = L2
Tap = H2
191
63
L1
H2
255
L2
SC
0
L1
SAM Low Half
63
L2
127
128
H1
SAM High Half
191
H2
255
Figure 24. Example of Split-Register Operation With Programmable Stop Points
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27
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
256-/512-bit compatibility of split-register programmable stop point
The stop-point mode is designed to be compatible with both 256-bit SAM and 512-bit SAM devices. After the
CBRS cycle is initiated, the stop-point mode becomes active. In the stop-point mode, column-address bits AY7
and AY8 are internally swapped to assure compatibility (see Figure 25). This address-bit swap applies to the
column address and is effective for all DRAM and transfer cycles. For example, during the split-register-transfer
cycle with stop point, column-address bit AY8 is a don’t care and AY7 decodes the DRAM row half for the
split-register-transfer. During stop-point mode, a CBR ( option reset ) cycle is not recommended because this
ends the stop-point mode and restores address bits AY7 and AY8 to their normal functions. Consistent use of
CBR cycles ensures that the SMJ55166 remains in normal mode.
NONSTOP POINT MODE
AY8 = 0
AY8 = 1
AY7 = 0 AY7 = 1 AY7 = 0 AY7 = 1
0
STOP-POINT MODE
AY8 = 0
AY8 = 1
AY7 = 0 AY7 = 1 AY7 = 0 AY7 = 1
512 × 512
Memory Array
512 × 512
Memory Array
256 - Bit
Data Register
256 - Bit
Data Register
255
0
255
Figure 25. DRAM-to-SAM Mapping, Nonstop Point Versus Stop Point
IMPORTANT: For proper device operation, a stop-point-mode (CBRS) cycle should be initiated immediately
after the power-up initialization cycles are performed.
power up
To achieve proper device operation, an initial pause of 200 µs is required after power up followed by a minimum
of eight RAS cycles or eight CBR cycles to initialize the DRAM port. A full-register-transfer read cycle and two
SC cycles are required to initialize the SAM port.
After initialization, the internal state of the SMJ55166 is as follows:
STATE AFTER INITIALIZATION
QSF
Write mode
Write-mask register
Color register
Serial-register tap point
SAM port
28
Defined by the transfer cycle during initialization
Nonpersistent mode
Undefined
Undefined
Defined by the transfer cycle during initialization
Output mode
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 1 V to 7 V
Voltage range on any pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 1 V to 7 V
Short-circuit output current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 mA
Power dissipation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1 W
Operating free-air temperature range, TA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 55°C to 125°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . – 65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: All voltage values are with respect to VSS.
recommended operating conditions
MIN
NOM
MAX
4.5
5
5.5
UNIT
VCC
VSS
Supply voltage
VIH
VIL
High-level input voltage
2.4
6.5
V
Low-level input voltage (see Note 2)
–1
0.8
V
Supply voltage
0
V
V
TA
Operating free-air temperature
– 55
125
°C
NOTE 2: The algebraic convention, where the more negative (less positive) limit is designated as minimum, is used for logic-voltage levels only.
electrical characteristics over recommended ranges of supply voltage and operating free-air
temperature (unless otherwise noted)
TEST CONDITIONS‡
PARAMETER
VOH
VOL
High-level output voltage
SAM
PORT
IOH = – 1 mA
IOL = 2 mA
Low-level output voltage
’55166-75
’55166- 80
MIN
MIN
MAX
2.4
MAX
2.4
UNIT
V
0.4
0.4
V
± 10
± 10
µA
± 10
± 10
µA
II
Input current (leakage)
VCC = 5.5 V,
VI = 0 V to 5.8 V,
All other pins at 0 V to VCC
IO
ICC1
Output current (leakage) (see Note 3)
Operating current §
VCC = 5.5 V, VO = 0 V to VCC
See Note 4
Standby
165
160
mA
ICC1A
ICC2
Operating current §
tc(SC) = MIN
All clocks = VCC
Active
210
195
mA
Standby
12
12
mA
ICC2A
ICC3
Standby current
Active
70
65
mA
RAS-only refresh current
tc(SC) = MIN
See Note 4
Standby
165
160
mA
ICC3A
ICC4
RAS-only refresh current
Page-mode current §
tc(SC) = MIN,
tc(P) = MIN,
(See Note 4)
Active
215
195
mA
(See Note 5)
Standby
100
95
mA
ICC4A
ICC5
Page-mode current §
tc(SC) = MIN,
See Note 4
(See Note 5)
Active
145
130
mA
Standby
165
160
mA
ICC5A
ICC6
CBR current
tc(SC) = MIN,
See Note 4
(See Note 4)
Active
210
195
mA
Standby
180
170
mA
225
200
mA
Standby current
CBR current
Data-transfer current
ICC6A
Data-transfer current
tc(SC) = MIN
Active
‡ For conditions shown as MIN / MAX, use the appropriate value specified in the timing requirements.
§ Measured with outputs open
NOTES: 3. SE is disabled for SQ output leakage tests.
4. Measured with one address change while RAS = VIL and tc(rd ), tc( W ), tc( TRD) = MIN
5. Measured with one address change while CASx = VIH
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
capacitance over recommended ranges of supply voltage and operating free-air temperature,
f = 1 MHz (see Note 6)
TYP
MAX
Ci(A)
Input capacitance, A0 – A8
PARAMETER
MIN
5
10
UNIT
pF
Ci(RC)
Input capacitance, CAS and RAS
8
10
pF
Ci(W)
Input capacitance, WEL and WEU
7
10
pF
Ci(SC)
Input capacitance, SC
6
10
pF
Ci(SE)
Input capacitance, SE
7
10
pF
Ci(DSF)
Input capacitance, QSF
7
10
pF
Ci(TRG)
Input capacitance, TRG
7
10
pF
Co(O)
Output capacitance, SQ and DQ
12
15
pF
Co(QSF)
Output capacitance, QSF
10
12
pF
NOTE 6: VCC = 5 V ± 0.5 V, and the bias on pins under test is 0 V.
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature (see Note 7)
PARAMETER
TEST
CONDITIONS †
ALT.
SYMBOL
’55166 - 75
’55166 - 80
MIN
MIN
MAX
MAX
UNIT
ta(C)
Access time from CAS
td(RLCL) = MAX
tCAC
20
20
ns
ta(CA)
Access time from column address
td(RLCL) = MAX
tAA
38
40
ns
ta(CP)
Access time from CAS high
td(RLCL) = MAX
tCPA
43
45
ns
ta(R)
Access time from RAS
td(RLCL) = MAX
tRAC
75
80
ns
ta(G)
Access time of DQ from TRG low
tOEA
20
20
ns
ta(SQ)
Access time of SQ from SC high
CL = 30 pF
tSCA
23
25
ns
ta(SE)
Access time of SQ from SE low
CL = 30 pF
tSEA
18
20
ns
tdis(CH)
Disable time, random output from CAS high
(see Note 8)
CL = 50 pF
tOFF
tdis(RH)
Disable time, random output from RAS high
(see Note 8)
CL = 50 pF
tdis(G)
Disable time, random output from TRG high
(see Note 8)
CL = 50 pF
tdis(WL)
Disable time, random output from WE low
(see Note 8)
CL = 50 pF
0
20
0
20
ns
0
20
0
20
ns
tOEZ
0
20
0
20
ns
tWEZ
0
25
0
25
ns
tdis(SE) Disable time, serial output from SE high (see Note 8)
CL = 30 pF
tSEZ
0
18
0
20
ns
† For conditions shown as MIN / MAX, use the appropriate value specified in the timing requirements.
NOTES: 7. Switching times for RAM-port output are measured with a load equivalent to 1 TTL load and 50 pF. Data-out reference level:
VOH / VOL = 2 V/0.8 V. Switching times for SAM-port output are measured with a load equivalent to 1 TTL load and 30 pF.
Serial-data-out reference level: VOH / VOL = 2 V/0.8 V.
8. tdis(CH), tdis(RH), tdis(G), tdis( WL ), and tdis(SE) are specified when the output is no longer driven.
30
POST OFFICE BOX 1443
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
timing requirements over recommended ranges of supply voltage and operating free-air
temperature†
ALT.
SYMBOL
tc(rd)
tc(W)
Cycle time, read
tc(rdW)
tc(P)
Cycle time, read-modify-write
tc(RDWP)
tc(TRD)
Cycle time, page-mode read-modify-write
tc(SC)
tw(CH)
Cycle time, SC (see Note 9)
tw(CL)
tw(RH)
Pulse duration, CAS low (see Note 10)
tw(RL)
tw(WL)
Pulse duration, RAS low (see Note 11)
tw(TRG)
tw(SCH)
Pulse duration, TRG low
Pulse duration, SC high
tw(SCL)
tw(GH)
Pulse duration, SC low
tw(RL)P
tsu(CA)
Pulse duration, RAS low (page mode)
tsu(SFC)
tsu(RA)
Setup time, DSF before CAS low
tsu(WMR)
tsu(DQR)
Setup time, WEx before RAS low
tsu(TRG)
tsu(SFR)
Setup time, TRG high before RAS low
tsu(DCL)
tsu(DWL)
Setup time, data valid before CAS low
tsu(rd)
tsu(WCL)
Setup time, read command, WEx high before CAS low
tsu(WCH)
tsu(WRH)
Setup time, WEx low before CAS high, write
Cycle time, write
Cycle time, page-mode read, write
Cycle time, transfer read
Pulse duration, CAS high
Pulse duration, RAS high
Pulse duration, WEx low
Pulse duration, TRG high
Setup time, row address before RAS low
Setup time, DQ before RAS low
Setup time, DSF low before RAS low
Setup time, data valid before WEx low
Setup time, early write command, WEx low before CAS low
MAX
’55166 - 80
MIN
MAX
UNIT
tRC
tWC
140
150
ns
140
150
ns
tRMW
tPC
188
200
ns
48
50
ns
tPRMW
tRC
88
90
ns
140
150
ns
tSCC
tCPN
24
30
ns
10
10
ns
tCAS
tRP
20
tRAS
tWP
75
10 000
55
20
10 000
60
10 000
80
ns
ns
10 000
ns
13
15
ns
20
20
ns
tSC
9
10
ns
tSCP
tTP
9
10
ns
20
20
ns
75 100 000
80 100 000
ns
tRASP
tASC
Setup time, column address before CAS low
’55166 -75
MIN
0
0
ns
tFSC
tASR
0
0
ns
0
0
ns
tWSR
tMS
0
0
ns
0
0
ns
tTHS
tFSR
0
0
ns
0
0
ns
tDSC
tDSW
tRCS
0
0
ns
0
0
ns
0
0
ns
0
0
ns
18
20
ns
tWCS
tCWL
Setup time, WEx low before RAS high, write
tRWL
20
20
ns
th(CLCA)
Hold time, column address after CAS low
tCAH
13
15
ns
th(SFC)
Hold time, DSF after CAS low
tCFH
15
15
ns
† Timing measurements are referenced to VIL MAX and VIH MIN.
NOTES: 9. Cycle time assumes tt = 3 ns.
10. In a read-modify-write cycle, td(CLWL) and tsu(WCH) must be observed. Depending on the user’s transition times, this can require
additional CAS low time [tw(CL)].
11. In a read-modify-write cycle, td(RLWL) and tsu(WRH) must be observed. Depending on the user’s transition times, this can require
additional RAS low time [tw(RL)].
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31
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
timing requirements over recommended ranges of supply voltage and operating free-air
temperature (continued)†
ALT.
SYMBOL
th(RA)
th(TRG)
Hold time, row address after RAS low
th(RWM)
th(RDQ)
Hold time, write mask after RAS low
th(SFR)
th(RLCA)
Hold time, DSF after RAS low
th(CLD)
th(RLD)
Hold time, data valid after CAS low
th(WLD)
th(CHrd)
Hold time, data valid after WEx low
th(RHrd)
th(CLW)
Hold time, read, WEx high after RAS high (see Note 13)
th(RLW)
th(WLG)
Hold time, write, WEx low after RAS low (see Note 12)
th(SHSQ)
th(RSF)
Hold time, SQ after SC high
th(CLQ)
Hold time, Output after CAS low
Hold time, TRG after RAS low
Hold time, DQ after RAS low (write-mask operation)
Hold time, column address valid after RAS low (see Note 12)
Hold time, data valid after RAS low (see Note 12)
Hold time, read, WEx high after CAS high (see Note 13)
Hold time, write, WEx low after CAS low
Hold time, TRG high after WEx low (see Note 14)
Hold time, DSF after RAS low
td(RLCH)
Dela time,
Delay
time RAS low
lo to CAS high
td(CHRL)
td(CLRH)
Delay time, CAS high to RAS low
td(CLWL)
td(RLCL)
Delay time, CAS low to WEx low (see Notes 16 and 17)
td(CARH)
td(CACH)
Delay time, column address valid to RAS high
td(RLWL)
td(CAWL)
Delay time, RAS low to WEx low (see Note 16)
td(CLRL)
td(RHCL)
Delay time, CAS low to RAS low (see Note 15)
(See Note 15)
Delay time, RAS low to CAS low (see Note 18)
Delay time, column address valid to CAS high
Delay time, column address valid to WEx low (see Note 16)
Delay time, RAS high to CAS low (see Note 15)
’55166 - 80
MIN
MIN
MAX
POST OFFICE BOX 1443
UNIT
10
10
ns
15
15
ns
tRWH
tMH
15
15
ns
15
15
ns
tRFH
tAR
10
10
ns
33
35
ns
tDH
tDHR
tDH
15
15
ns
35
35
ns
15
15
ns
tRCH
tRRH
0
0
ns
0
0
ns
tWCH
tWCR
15
15
ns
35
35
ns
tOEH
tSOH
10
10
ns
2
2
ns
tFHR
tDHC
35
35
ns
0
0
ns
tCSH
tCHR
75
80
13
15
0
0
ns
20
ns
tCWD
tRCD
48
tRAL
tCAL
38
tRWD
tAWD
tCSR
tRPC
• HOUSTON, TEXAS 77251–1443
ns
20
20
50
50
20
ns
60
ns
40
ns
38
40
ns
95
100
ns
63
65
ns
0
0
ns
0
td(CLGH) Delay time, CAS low to TRG high for DRAM read cycles
20
td(GHD)
Delay time, TRG high before data applied at DQ
tOED
15
† Timing measurements are referenced to VIL MAX and VIH MIN.
NOTES: 12. The minimum value is measured when td(RLCL) is set to td(RLCL) MIN as a reference.
13. Either th(RHrd) or th(CHrd) must be satisfied for a read cycle.
14. Output-enable-controlled write; the output remains in the high-impedance state for the entire cycle.
15. CBR refresh operation only
16. Read-modify-write operation only
17. TRG must disable the output buffers prior to applying data to the DQ pins.
18. The maximum value is specified only to assure RAS access time.
32
MAX
tRAH
tTHH
tCRP
tRSH
Delay time, CAS low to RAS high
’55166 -75
0
ns
20
ns
15
ns
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
timing requirements over recommended ranges of supply voltage and operating free-air
temperature (continued)†
ALT.
SYMBOL
td(RLTH)
td(RLSH)
Delay time, RAS low to TRG high (see Note 19)
td(RLCA)
td(GLRH)
Delay time, RAS low to column address valid
td(CLSH)
td(SCTR)
Delay time, CAS low to first SC high after TRG high (see Note 20)
td(THRH)
td(THRL)
Delay time, TRG high to RAS high (see Note 19)
’55166 -75
’55166 - 80
MIN
MIN
MAX
MAX
tRTH
tRSD
58
tRAD
tROH
15
20
20
ns
tCSD
tTSL
23
25
ns
5
5
ns
tTRD
tTRP
– 10
– 10
ns
Delay time, TRG high to RAS low (see Note 21)
55
60
ns
td(THSC)
Delay time, TRG high to SC high (see Note 19)
tTSD
18
20
ns
td(RHMS)
Delay time, RAS high to last (most significant) rising edge of SC before
boundary switch during split-register-transfer read cycles
20
20
ns
td(CLTH)
td(CASH)
td(CAGH)
td(DCL)
td(DGL)
Delay time, RAS low to first SC high after TRG high (see Note 20)
Delay time, TRG low to RAS high
Delay time, SC high to TRG high (see Notes 19 and 20)
Delay time, CAS low to TRG high in real-time-transfer read cycles
60
UNIT
75
ns
80
35
15
ns
40
ns
tCTH
tASD
15
15
ns
Delay time, column address to first SC in early-load-transfer read cycles
28
30
ns
Delay time, column address to TRG high in real-time-transfer read
cycles
tATH
20
20
ns
tDZC
tDZO
0
0
ns
0
0
ns
20
20
ns
Delay time, data to CAS low
Delay time, data to TRG low
td(MSRL)
Delay time, last (most significant) rising edge of SC to RAS low before
boundary switch during split-transfer read cycles
td(SCQSF)
Delay time, last (127 or 255) rising edge of SC to QSF switching at the
boundary during split-register-transfer read cycles (see Note 22)
tSQD
28
30
ns
td(CLQSF)
Delay time, CAS low to QSF switching in transfer read cycles
(see Note 22)
tCQD
33
35
ns
td(GHQSF)
Delay time, TRG high to QSF switching in transfer read cycles
(see Note 22)
tTQD
28
30
ns
td(RLQSF)
Delay time, RAS low to QSF switching in transfer read cycles
(see Note 22)
tRQD
73
75
ns
trf(MA)
Refresh time interval, memory
tREF
8
8
ms
tt
Transition time
tT
3
50
3
50
ns
† Timing measurements are referenced to VIL MAX and VIH MIN.
NOTES: 19. Real-time-load transfer read or late-load-transfer read cycle only
20. Early-load-transfer read cycle only
21. Full-register-(read) transfer cycles only
22. Switching times for QSF output are measured with a load equivalent to 1 TTL load and 30 pF, and the output reference level is
VOH / VOL = 2 V/0.8 V.
POST OFFICE BOX 1443
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(rd)
tw(RL)
td(RLCH)
RAS
tw(RH)
tt
td(CLRH)
td(RLCL)
tw(CL)
td(CHRL)
CAS
tw(CH)
td(CACH)
td(RLCA)
td(CARH)
th(RA)
th(RLCA)
tsu(RA)
th(CLCA)
tsu(CA)
Row
A0 – A8
Column
th(SFR)
tsu(SFR)
DSF
td(CLGH)
tsu(TRG)
td(GLRH)
tw(TRG)
th(TRG)
TRG
th(RHrd)
tsu(rd)
th(CHrd)
WEx
tdis(CH)
td(DGL)
DQ0 – DQ15
ta(G)
Data In
tdis(G)
Data Out
ta(C)
ta(CA)
ta(R)
Figure 26. Read-Cycle Timing With CAS-Controlled Output
34
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(rd)
tw(RL)
td(RLCH)
RAS
tw(RH)
tt
td(CLRH)
td(RLCL)
tw(CL)
td(CHRL)
CAS
tw(CH)
td(RLCA)
td(CARH)
th(RA)
th(RLCA)
td(CACH)
tsu(RA)
th(CLCA)
tsu(CA)
Row
A0 – A8
Column
th(SFR)
tsu(SFR)
DSF
td(CLGH)
td(GLRH)
tw(TRG)
tsu(TRG)
th(TRG)
TRG
tsu(rd)
th(RHrd)
th(CHrd)
WEx
td(DGL)
DQ0 – DQ15
ta(G)
Data In
tdis(G)
tdis(RH)
Data Out
ta(C)
ta(CA)
ta(R)
Figure 27. Read-Cycle Timing With RAS-Controlled Output
POST OFFICE BOX 1443
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35
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
td(RLCH)
tt
tw(RH)
td(CLRH)
tt
td(CHRL)
td(RLCL)
td(CHRL)
tw(CL)
CAS
tw(CH)
th(RLCA)
td(CACH)
tsu(CA)
th(CLCA)
th(RA)
td(RLCA)
td(CARH)
tsu(RA)
Row
A0 – A8
Column
tsu(SFC)
tsu(SFR)
th(RSF)
th(SFR)
th(SFC)
DSF
th(TRG)
tsu(TRG)
TRG
tsu(WCH)
tsu(WMR)
tsu(WRH)
th(RLW)
th(CLW)
tsu(WCL)
tw(WL)
th(RWM)
1
WEx
tsu(DQR)
th(CLD)
tsu(DCL)
th(RDQ)
DQ0 – DQ15
th(RLD)
2
3
Figure 28. Early-Write-Cycle Timing
Table 6. Early-Write-Cycle State Table
STATE
CYCLE
1
2
3
Write operation (nonmasked)
H
Don’t care
Valid data
Write operation with nonpersistent write-per-bit
L
Write mask
Valid data
Write operation with persistent write-per-bit
L
Don’t care
Valid data
36
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
td(RLCH)
tt
td(CLRH)
td(CHRL)
td(RLCL)
td(CHRL)
tt
tw(CL)
CAS
td(RLCA)
th(RLCA)
tw(CH)
tsu(CA)
th(CLCA)
td(CACH)
th(RA)
tsu(RA)
td(CARH)
Row
A0 – A8
Column
th(RSF)
tsu(SFC)
tsu(SFR)
th(SFR)
th(SFC)
DSF
tsu(rd)
TRG
tsu(WRH)
tsu(WCH)
tsu(TRG)
th(CLW)
td(GHD)
th(RLW)
tsu(WMR)
th(WLG)
th(RWM)
WEx
tw(WL)
1
tsu(DWL)
tsu(DQR)
th(WLD)
th(RDQ)
th(RLD)
2
DQ0 – DQ15
3
Figure 29. Late-Write-Cycle Timing (Output-Enable-Controlled Write)
Table 7. Late-Write-Cycle State Table
STATE
CYCLE
1
2
3
Write operation (nonmasked)
H
Don’t care
Valid data
Write operation with nonpersistent write-per-bit
L
Write mask
Valid data
Write operation with persistent write-per-bit
L
Don’t care
Valid data
POST OFFICE BOX 1443
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37
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
td(RLCH)
tt
td(CLRH)
tt
td(CHRL)
td(RLCL)
td(CHRL)
tw(CL)
CAS
tw(CH)
th(RA)
Refresh Row
tsu(RA)
A0 – A8
tsu(SFC)
tsu(SFR)
th(RSF)
th(SFC)
th(SFR)
DSF
th(TRG)
tsu(TRG)
TRG
tsu(WCH)
tsu(WMR)
tsu(WRH)
th(RLW)
th(CLW)
th(RWM)
tsu(WCL)
tw(WL)
WEx
tsu(DCL)
th(CLD)
th(RLD)
DQ0 – DQ15
Write Mask†
† Load-write-mask-register cycle puts the device into the persistent write-per-bit mode.
Figure 30. Load-Write-Mask-Register-Cycle Timing (Early-Write Load)
38
POST OFFICE BOX 1443
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
td(RLCH)
tt
td(CLRH)
td(CHRL)
td(RLCL)
td(CHRL)
tt
tw(CL)
CAS
tw(CH)
th(RA)
Refresh Row
tsu(RA)
A0 – A8
th(RSF)
tsu(SFR)
tsu(SFC)
th(SFR)
th(SFC)
DSF
tsu(WRH)
TRG
tsu(WCH)
tsu(TRG)
th(CLW)
td(GHD)
th(RLW)
tsu(WMR)
th(WLG)
th(RWM)
tw(WL)
WEx
tsu(DWL)
th(WLD)
th(RLD)
Write Mask†
DQ0 – DQ15
† Load-write-mask-register cycle puts the device into the persistent write-per-bit mode.
Figure 31. Load-Write-Mask-Register-Cycle Timing (Late-Write Load)
POST OFFICE BOX 1443
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39
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(rdW)
tw(RL)
td(RLCH)
RAS
td(CHRL)
td(RLCL)
tsu(CA)
tsu(RA)
tw(CH)
th(CLCA)
th(RLCA)
td(CACH)
td(RLCA)
A0 – A8
td(CHRL)
tw(CL)
th(RA)
CAS
tw(RH)
td(CLRH)
td(CARH)
Row
Column
th(RSF)
tsu(SFR)
th(SFC)
tsu(SFC)
th(SFR)
DSF
tsu(WCH)
tsu(rd)
th(TRG)
tsu(WRH)
td(CAWL)
tw(TRG)
TRG
th(WLG)
th(RLW)
th(CLW)
tsu(TRG)
td(CLWL)
tsu(WMR)
td(DCL)
th(RWM)
WEx
td(CLGH)
td(RLWL)
ta(R)
th(WLD)
td(DGL)
tsu(DQR)
th(RDQ)
DQ0 – DQ15
tw(WL)
ta(CA)
1
td(GHD)
ta(C)
tsu(DWL)
Valid
Out
2
ta(G)
3
tdis(G)
Figure 32. Read-Write-/Read-Modify-Write-Cycle Timing
Table 8. Read-Write-/Read-Modify-Write-Cycle State Table
STATE
CYCLE
1
2
3
Write operation (nonmasked)
H
Don’t care
Valid data
Write operation with nonpersistent write-per-bit
L
Write mask
Valid data
Write operation with persistent write-per-bit
L
Don’t care
Valid data
40
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tw(RH)
tw(RL)P
RAS
td(RLCL)
td(CHRL)
CAS
td(CLRH)
tw(CH)
tw(CL)
tt
td(RLCA)
td(RLCH)
tsu(RA)
tsu(CA)
tc(P)
td(CACH)
th(CLCA)
th(RA)
td(CARH)
th(RLCA)
Row
A0 – A8
Column
Column
th(SFR)
td(CLGH)
tsu(SFR)
DSF
th(TRG)
tsu(TRG)
TRG
tsu(WMR)
tsu(rd)
th(RHrd)
WEx
ta(C)
ta(CA)
td(DGL)
ta(CA)†
ta(G)
ta(R)‡
0–
15
th(CLQ)
ta(CP)†
Data Out
Data In
tdis(WL)
tdis(RH)
tdis(G)
Data Out
td(DCL)
† Access time is ta(CP) or ta(CA) dependent.
‡ DQ outputs can go from the high-impedance state to an invalid-data state prior to the specified access time.
NOTE A: A write cycle or a read-modify-write cycle can be mixed with the read cycles as long as the write and read-modify-write timing
specifications are not violated and the proper polarity of DSF is selected on the falling edge of RAS and CAS to select the desired
write mode (normal, block write, etc.).
Figure 33. Enhanced-Page-Mode Read-Cycle Timing
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
41
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tw(RL)P
RAS
td(RLCH)
td(RLCL)
tc(P)
tw(CH)
td(CHRL)
tsu(RA)
tw(CL)
td(RLCA)
tsu(CA)
CAS
tw(RH)
td(CLRH)
td(CHRL)
th(RA)
td(CACH)
th(CLCA)
td(CARH)
th(RLCA)
A0 –
A8
Row
Column
Column
tsu(SFR)
td(RSF)
th(SFC)
th(SFC)
th(SFR)
tsu(SFC)
tsu(SFC)
DSF
1
2
2
tsu(TRG)
th(TRG)
TRG
See Note A
tsu(WMR)
th(RWM)
WEx
tsu(WCH)
tsu(WCH)
tsu(WRH)
tw(WL)
3
tsu(DWL)†
tsu(DQR)
th(CLD)†
tsu(DCL)†
th(WLD)†
th(RDQ)
th(RLD)
–
5
4
5
5
† Referenced to the first falling edge of WEx or the falling edge of CAS, whichever occurs later
NOTE A: A read cycle or a read-modify-write cycle can be intermixed with write cycles, observing read and read-modify-write timing
specifications. To ensure page-mode cycle time, TRG must remain high throughout the entire page-mode operation if the late-write
feature is used. If the early-write-cycle timing is used, the state of TRG is a don’t care after the minimum period th(TRG) from the falling
edge of RAS.
Figure 34. Enhanced-Page-Mode Write-Cycle Timing
Table 9. Enhanced-Page-Mode Write-Cycle State Table
STATE
CYCLE
1
2
3
4
5
Write operation (nonmasked)
L
L
H
Don’t care
Valid data
Write operation with nonpersistent write-per-bit
L
L
L
Write mask
Valid data
Write operation with persistent write-per-bit
L
L
L
Don’t care
Valid data
Load-write-mask register on either the first falling edge of
H
L
H
Don’t care
Write mask
WEx or the falling edge of CAS, whichever occurs later.‡
‡ Load-write-mask-register cycle puts the device in the persistent write-per-bit mode. Column address at the falling edge of CAS is a don’t care
during this cycle.
42
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tw(RL)P
RAS
td(RLCH)
td(CHRL)
td(RLCL)
td(RLCA)
td(CARH)
tsu(CA)
th(CLCA)
tsu(RA)
td(CACH)
th(RLCA)
A0 – A8
td(CHRL)
tw(CH)
tw(CL)
th(RA)
CAS
Row
Column
Column
th(SFR)
tsu(SFR)
tsu(SFC)
th(SFC)
th(SFC)
tsu(SFC)
DSF
tw(RH)
td(CLRH)
tc(RDWP)
1
2
2
tsu(rd)
tsu(WCH)
tsu(WCH)
td(CLWL)
td(DCL)
td(CAWL)
td(CLGH)
td(RLWL)
th(TRG)
td(CLGH)
tsu(TRG)
tsu(WRH)
tw(TRG)
TRG
tw(TRG)
tsu(WMR)
th(RWM)
tw(WL)
ta(C)†
3
WEx
ta(CA)†
tsu(DWL)
th(WLD)
tsu(DQR)
th(WLD)
td(DCL)
tsu(DWL)
th(RDQ)
DQ0 – DQ15
4
Valid Out
5
5
ta(G)†
td(DGL)
ta(R)†
td(GHD)
ta(CP)†
td(DGL)
Valid Out
tdis(G)
td(GHD)
ta(C)†
† Output can go from the high-impedance state to an invalid-data state prior to the specified access time.
NOTE A: A read or a write cycle can be intermixed with read-modify-write cycles as long as the read and write timing specifications are not violated.
Figure 35. Enhanced-Page-Mode Read-Modify-Write-Cycle Timing
Table 10. Enhanced-Page-Mode Read-Modify-Write-Cycle State Table
STATE
CYCLE
1
2
3
4
5
Write operation (nonmasked)
L
L
Write operation with nonpersistent write-per-bit
L
L
H
Don’t care
Valid data
L
Write mask
Write operation with persistent write-per-bit
L
L
Valid data
L
Don’t care
Valid data
Load-write-mask register on either the first falling edge of
H
L
H
Don’t care
Write mask
WEx or the falling edge of CAS, whichever occurs later.‡
‡ Load-write-mask-register cycle sets the device to the persistent write-per-bit mode. Column address at the falling edge of CAS is a don’t care
during this cycle.
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
43
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tw(RH)
tw(RL)P
RAS
td(RLCL)
td(CHRL)
CAS
td(CLRH)
tw(CH)
tw(CL)
tt
td(RLCA)
td(RLCH)
tsu(RA)
tsu(CA)
tc(P)
td(CACH)
th(CLCA)
th(RA)
td(CARH)
th(RLCA)
Row
A0 – A8
Column
Column
th(SFR)
td(CLGH)
tsu(SFR)
DSF
tsu(WCL)
th(TRG)
tsu(TRG)
th(CLW)
TRG
tsu(WMR)
tsu(rd)
WEx
tw(WL)
ta(C)
ta(CA)†
td(DGL)
ta(R)‡
–
5
th(CLD)
ta(G)
Data In
tsu(DCL)
tdis(WL)
Data Out
Data In
td(DCL)
† Access time is ta(CP) or ta(CA) dependent.
‡ Output can go from the high-impedance state to an invalid-data state prior to the specified access time.
NOTE A: A write cycle or a read-modify-write cycle can be mixed with the read cycles as long as the write and read-modify-write timing
specifications are not violated and the proper polarity of DSF is selected on the falling edge of RAS and CAS to select the desired write
mode (normal, block write, etc.).
Figure 36. Enhanced-Page-Mode Read- / Write-Cycle Timing
44
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
tt
td(RLCH)
tt
td(CHRL)
td(CLRH)
td(RLCL)
tw(CL)
td(CHRL)
CAS
th(RA)
tw(CH)
tsu(RA)
Refresh Row
A0 – A8
th(SFC)
th(RSF)
tsu(SFR)
tsu(SFC)
th(SFR)
DSF
tsu(TRG)
th(TRG)
TRG
tsu(WCH)
tsu(WRH)
tsu(WMR)
th(RLW)
th(RWM)
th(CLW)
tsu(WCL)
WEx
tw(WL)
tsu(DCL)
th(CLD)
th(RLD)
DQ0 –
DQ15
Valid-Color Input
Figure 37. Load-Color-Register-Cycle Timing (Early-Write Load)
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
45
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
tt
td(RLCH)
tt
td(CLRH)
td(RLCL)
td(CHRL)
td(CHRL)
tw(CL)
CAS
th(RSF)
th(RA)
tsu(RA)
tw(CH)
Refresh Row
A0 – A8
th(SFC)
tsu(SFR)
tsu(SFC)
th(SFR)
DSF
tsu(TRG)
th(CLW)
TRG
tsu(WRH)
tsu(WCH)
td(GHD)
th(RLW)
tsu(WMR)
th(WLG)
tw(WL)
WEx
tsu(DWL)
th(WLD)
th(RLD)
DQ0 –
DQ15
Valid-Color Input
Figure 38. Load-Color-Register-Cycle Timing (Late-Write Load)
46
POST OFFICE BOX 1443
• HOUSTON, TEXAS 77251–1443
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
tt
td(RLCH)
td(RLCL)
tt
td(CLRH)
td(CHRL)
td(CHRL)
tw(CL)
CAS
td(RLCA)
tw(CH)
th(CLCA)
th(RLCA)
td(RLCA)
tsu(RA)
td(CARH)
td(CACH)
th(RA)
tsu(CA)
Row
A0 – A8
td(RSF)
Block Address
A2 – A8
tsu(SFR)
tsu(SFC)
th(SFR)
th(SFC)
DSF
th(TRG)
tsu(TRG)
TRG
tsu(WCH)
th(RWM)
tsu(WRH)
tsu(WCL)
tsu(WMR)
th(CLW)
th(RLW)
tw(WL)
1
WEx
th(RLD)
tsu(DCL)
tsu(DQR)
th(CLD)
th(RDQ)
DQ0 – DQ15
2
3
Figure 39. Block-Write-Cycle Timing (Early Write)
Table 11. Block-Write-Cycle State Table
STATE
CYCLE
1
2
3
Block-write operation (nonmasked)
H
Don’t care
Column mask
Block-write operation with nonpersistent write-per-bit
L
Write mask
Column mask
Block-write operation with persistent write-per-bit
L
Don’t care
Column mask
Write-mask data
0: I/O write disable
1: I/O write enable
Column-mask data DQi – DQi + 3
0: column write disable
(i = 0, 4, 8, 12)
1: column write enable
POST OFFICE BOX 1443
Example:
DQ0 — column 0 (address A1 = 0, A0 = 0)
DQ1 — column 1 (address A1 = 0, A0 = 1)
DQ2 — column 2 (address A1 = 1, A0 = 0)
DQ3 — column 3 (address A1 = 1, A0 = 1)
• HOUSTON, TEXAS 77251–1443
47
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(W)
tw(RL)
RAS
tw(RH)
tt
td(RLCH)
tt
td(CLRH)
td(RLCL)
td(CHRL)
td(CHRL)
tw(CL)
CAS
tw(CH)
td(RLCA)
td(CACH)
th(RLCA)
td(CARH)
th(RA)
tsu(CA)
tsu(RA)
th(CLCA)
Row
A0 – A8
th(RSF)
tsu(SFR)
Block Address
A2 – A8
tsu(SFC)
th(SFR)
th(SFC)
DSF
tsu(TRG)
th(CLW)
tsu(WCH)
TRG
td(GHD)
th(RLW)
tsu(WRH)
tsu(WMR)
th(WLG)
th(RWM)
WEx
tw(WL)
1
tsu(DQR)
tsu(DWL)
th(RDQ)
th(WLD)
th(RLD)
DQ0 – DQ15
3
2
Figure 40. Block-Write-Cycle Timing (Late Write)
Table 12. Block-Write-Cycle State Table
CYCLE
STATE
1
2
3
Block-write operation (nonmasked)
H
Don’t care
Column mask
Block-write operation with nonpersistent write-per-bit
L
Write mask
Column mask
Block-write operation with persistent write-per-bit
L
Don’t care
Column mask
Write-mask data
0: I/O write disable
1: I/O write enable
Column-mask data DQi – DQi + 3
0: column write disable
(i = 0, 4, 8, 12)
1: column write enable
48
POST OFFICE BOX 1443
Example:
DQ0 — column 0 (address A1 = 0, A0 = 0)
DQ1 — column 1 (address A1 = 0, A0 = 1)
DQ2 — column 2 (address A1 = 1, A0 = 0)
DQ3 — column 3 (address A1 = 1, A0 = 1)
• HOUSTON, TEXAS 77251–1443
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tw(RL)P
RAS
td(RLCH)
td(RLCL)
td(CLRH)
tw(CH)
tw(CL)
td(CHRL)
CAS
td(RLCA)
td(CHRL)
th(CLCA)
tsu(CA)
td(CACH)
th(RA)
th(RLCA)
tsu(RA)
Row
A0 – A8
tw(RH)
tc(P)
td(CARH)
Block Address
A2 – A8
Block Address
A2 – A8
th(SFC)
tsu(SFC)
th(SFC)
tsu(SFC)
th(SFR)
tsu(SFR)
DSF
th(TRG)
tsu(TRG)
TRG
See Note A
tsu(WMR)
tw(WL)
th(RWM)
WEx
tsu(WCH)
tsu(WCH)
tsu(WRH)
1
tsu(DWL)†
th(CLD)†
th(WLD)†
tsu(DQR)
tsu(DCL)†
th(RDQ)
th(RLD)
DQ0 – DQ15
2
3
3
† Referenced to the first falling edge of WEx or the falling edge of CAS, whichever occurs later
NOTE A: To assure page-mode cycle time, TRG must remain high throughout the entire page-mode operation if the late-write feature is used.
If the early write-cycle timing is used, the state of TRG is a don’t care after the minimum period th(TRG) from the falling edge of RAS.
Figure 41. Enhanced-Page-Mode Block-Write-Cycle Timing
Table 13. Enhanced-Page-Mode Block-Write-Cycle State Table
STATE
CYCLE
1
2
3
Block-write operation (nonmasked)
H
Don’t care
Column mask
Block-write operation with nonpersistent write-per-bit
L
Write mask
Column mask
Block-write operation with persistent write-per-bit
L
Don’t care
Column mask
Write-mask data 0: I/O write disable
1: I/O write enable
Column-mask data DQi – DQi + 3
0: column write disable
(i = 0, 4, 8, 12) 1: column write enable
POST OFFICE BOX 1443
Example:
DQ0 — column 0 (address A1 = 0, A0 = 0)
DQ1 — column 1 (address A1 = 0, A0 = 1)
DQ2 — column 2 (address A1 = 1, A0 = 0)
DQ3 — column 3 (address A1 = 1, A0 = 1)
• HOUSTON, TEXAS 77251–1443
49
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(rd)
tw(RL)
RAS
tw(RH)
tt
td(RHCL)
td(CHRL)
CAS
th(RA)
tsu(RA)
Row
A0 – A8
DSF
tsu(TRG)
th(TRG)
TRG
WEx
DQ0 –
DQ15
Figure 42. RAS-Only Refresh-Cycle Timing
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td(CHRL)
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(rd)
tw(RH)
tw(RL)
RAS
td(RHCL)
tt
td(CLRL)
td(RLCH)
CAS
td(CHRL)
tsu(RA)
th(RA)
1
A0 – A8
tsu(SFR)
th(SFR)
2
DSF
TRG
tsu(WMR)
th(RWM)
3
WEx
DQ0 – DQ15
Figure 43. CBR-Refresh-Cycle Timing
Table 14. CBR-Cycle State Table
STATE
CYCLE
1
2
3
CBR refresh with option reset
Don’t care
L
H
CBR refresh with no reset
Don’t care
H
H
Stop address
H
L
CBR refresh with stop-point set and no reset
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
Memory Read Cycle
Refresh Cycle
tc(rd)
tc(rd)
tw(RL)
Refresh Cycle
tc(rd)
tw(RH)
tw(RH)
tw(RL)
RAS
td(CARH)
td(CHRL)
td(RLCH)
tt
tw(CL)
CAS
td(RLCA)
tsu(RA)
tsu(RA)
th(CLCA)
tsu(CA)
th(RA)
tsu(RA)
A0 – A8
Row
th(RA)
th(RA)
tsu(RA)
th(RA)
1
Col
1
1
tsu(SFR)
th(SFR)
tsu(SFR)
th(SFR)
th(SFR)
2
2
DSF
tsu(SFR)
2
th(RHrd)
tdis(CH)
tsu(TRG)
th(TRG)
tdis(G)
td(GLRH)
TRG
tsu(WMR)
th(RWM)
tsu(WMR)
th(RWM)
tsu(rd)
ta(G)
WEx
3
tsu(WMR)
th(RWM)
3
3
ta(C)
ta(R)
DQ0 –
DQ15
Data Out
Figure 44. Hidden-Refresh-Cycle Timing
Table 15. Hidden-Refresh-Cycle State Table
STATE
CYCLE
1
2
3
CBR refresh with option reset
Don’t care
L
H
CBR refresh with no reset
Don’t care
H
H
Stop address
H
L
CBR refresh with stop-point set and no option reset
52
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262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(TRD)
tw(RL)
td(RLCL)
RAS
tw(RH)
td(RLCH)
td(CHRL)
td(CARH)
tw(CL)
td(RLCA)
CAS
th(RA)
tsu(RA)
tsu(CA)
th(CLCA)
th(RLCA)
Tap Point
A0 – A8
Row
A0 – A8
tsu(SFR)
th(SFR)
DSF
tsu(TRG)
th(TRG)
TRG
tw(GH)
th(RWM)
tsu(WMR)
td(CASH)
WEx
DQ0 – DQ15
td(SCTR)
tw(SCH)
Hi-Z
td(CLSH)
tw(SCL)
td(RLSH)
SC
tw(SCH)
ta(SQ)
ta(SQ)
th(SHSQ)
th(SHSQ)
Old Data
SQ
tc(SC)
Old Data
New Data
td(GHQSF)
Tap Point Bit A7
QSF
td(CLQSF)
H
td(RLQSF)
SE
L
NOTES: A. DQ outputs remain in the high-impedance state for the entire memory-to-data-register transfer cycle. The memory-to-data-register
transfer cycle is used to load the data registers in parallel from the memory array. The 256 locations in each data register are written
into from the 256 corresponding columns of the selected row.
B. Once data is transferred into the data registers, the SAM is in the serial-read mode (i.e., the SQ is enabled), allowing data to be
shifted out of the registers. Also, the first bit to read from the data register after TRG has gone high must be activated by a positive
transition of SC.
C. A0 – A7: register tap point; A8: identifies the DRAM row half
D. Early-load operation is defined as th(TRG) min < th(TRG) < td(RLTH) min.
Figure 45. Full-Register-Transfer Read Timing, Early-Load Operations
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53
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(TRD)
tw(RL)
td(RLCL)
RAS
tw(RH)
td(RLCH)
td(CHRL)
CAS
tw(CL)
td(RLCA)
th(RA)
tsu(RA)
tsu(CA)
th(RLCA)
th(CLCA)
Tap Point
A0 – A8
Row
A0 – A8
tsu(SFR)
th(SFR)
DSF
td(CLTH)
tsu(TRG)
td(THRL)
td(THRH)
td(CAGH)
td(RLTH)
TRG
tw(GH)
th(RWM)
tsu(WMR)
WEx
td(SCTR)
td(THSC)
DQ0 – DQ15
Hi-Z
tw(SCH)
SC
ta(SQ)
th(SHSQ)
Old Data
SQ
tc(SC)
tw(SCL)
th(SHSQ)
Old Data
Old Data
ta(SQ)
New Data
td(GHQSF)
QSF
Tap Point Bit A7
td(CLQSF)
td(RLQSF)
H
SE
L
NOTES: A. DQ outputs remain in the high-impedance state for the entire memory-to-data-register transfer cycle. The memory-to-data-register
transfer cycle is used to load the data registers in parallel from the memory array. The 256 locations in each data register are written
into from the 256 corresponding columns of the selected row.
B. Once data is transferred into the data registers, the SAM is in the serial-read mode (i.e., the SQ is enabled), allowing data to be
shifted out of the registers. Also, the first bit to read from the data register after TRG has gone high must be activated by a positive
transition of SC.
C. A0 – A7: register tap point; A8: identifies the DRAM row half
D. Late load operation is defined as td(THRH) < 0 ns.
Figure 46. Full-Register-Transfer Read Timing, Real-Time Load Operation/Late-Load Operation
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
tc(TRD)
tw(RL)
tw(RH)
td(RLCL)
RAS
td(CHRL)
td(RLCH)
td(RLCA)
CAS
tw(CH)
tw(CL)
tsu(CA)
th(RA)
th(CLCA)
tsu(RA)
A0 – A8
Tap Point A0 – A8
Row
tsu(TRG)
See Note A
th(TRG)
TRG
th(SFR)
tsu(SFR)
DSF
th(RWM)
tsu(WMR)
WEx
Q0 –
Q15
Hi-Z
td(MSRL)
td(RHMS)
tc(SC)
tc(SC)
tw(SCH)
Bit 127
or 255
SC
tw(SCL)
ta(SQ)
th(SHSQ)
Bit 126 or
Bit 254
SQ
Bit 255
or 127
Tap
Point M
ta(SQ)
Bit 127 or
Bit 255
Tap
Point N
ta(SQ)
Tap Point M
tw(SCL)
Bit 127 or
Bit 255
Tap
Point N
ta(SQ)
td(SCQSF)
td(SCQSF)
QSF
MSB Old
New MSB
H
SE
L
NOTE A: A0 – A6: tap point of the given half; A7: don’t care; A8: identifies the DRAM row half
Figure 47. Split-Register-Transfer Read Timing
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
RAS
tsu(TRG)
th(TRG)
TRG
tc(SC)
tw(SCH)
tc(SC)
tw(SCH)
tw(SCH)
tw(SCL)
tw(SCL)
SC
ta(SQ)
th(SHSQ)
SQ
ta(SQ)
ta(SQ)
th(SHSQ)
Valid Out
th(SHSQ)
Valid Out
Valid Out
ta(SE)
SE
NOTES: A. While reading data through the serial-data register, TRG is a don’t care, but TRG must be held high when RAS goes low. This
is to avoid the initiation of a register-data-transfer operation.
B. The serial-data-out cycle is used to read data out of the data registers. Before data can be read via SQ, the device must be put
into the read mode by performing a transfer-read cycle.
Figure 48. Serial-Read-Cycle Timing (SE = VIL )
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262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
RAS
tsu(TRG)
th(TRG)
TRG
tc(SC)
tc(SC)
tw(SCH)
tw(SCH)
tw(SCL)
SC
tw(SCH)
tw(SCL)
ta(SQ)
ta(SQ)
ta(SQ)
th(SHSQ)
ta(SE)
SQ
Valid Out
Valid Out
th(SHSQ)
Valid Out
Valid Out
tdis(SE)
SE
NOTES: A. While reading data through the serial-data register, TRG is a don’t care, but TRG must be held high when RAS goes low. This
is to avoid the initiation of a register-data-transfer operation.
B. The serial-data-out cycle is used to read data out of the data registers. Before data can be read via SQ, the device must be
put into the read mode by performing a transfer-read cycle.
Figure 49. Serial-Read Timing (SE-Controlled Read)
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
PARAMETER MEASUREMENT INFORMATION
RAS
CAS
ADDR
Row Tap1
(low)
Row Tap1
(high)
Row Tap2
(low)
Row Tap2
(high)
TRG
DSF
CASE I
SC
Tap1
(low)
Bit
127
Tap1
(high)
Bit
255
Tap2
(low)
Bit
127
Bit
127
Tap1
(high)
Bit
255
Tap2
(low)
Bit
127
Bit
127
Tap1
(high)
Bit
255
Tap2
(low)
Bit
127
QSF
CASE II
SC
Tap1
(low)
QSF
CASE III
SC
Tap1
(low)
QSF
Full-Register-Transfer Read
Split Register to the
High Half of the
Data Register
Split Register to the
Low Half of the
Data Register
Split Register to the
High Half of the
Data Register
NOTES: A. To achieve proper split-register operation, a full-register-transfer read should be performed before the first split-register-transfer
cycle. This is necessary to initialize the data register and the starting tap location. First serial access can begin after the
full-register-transfer read cycle (CASE I), during the first split-register-transfer cycle (CASE II), or even after the first
split-register-transfer cycle (CASE III). There is no minimum requirement of SC clock between the full-register-transfer read cycle
and the first split-register cycle.
B. A split-register transfer into the inactive half is not allowed until td(MSRL) is met. td(MSRL) is the minimum delay time between the
rising edge of the serial clock of the last bit (bit 127 or 255) and the falling edge of RAS of the split-register-transfer cycle into the
inactive half. After the td(MSRL) is met, the split-register transfer into the inactive half must also satisfy the minimum td(RHMS)
requirement. td(RHMS) is the minimum delay time between the rising edge of RAS of the split-register-transfer cycle into the inactive
half and the rising edge of the serial clock of the last bit (bit 127 or 255).
Figure 50. Split-Register Operating Sequence
58
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SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
MECHANICAL DATA
GB (S-CPGA-P68)
CERAMIC PIN GRID ARRAY PACKAGE
0.970 (24,63)
0.950 (24,13)
0.536 (13,61)
0.524 (13,31)
0.800 (20,32) TYP
J
H
G
F
E
D
C
B
A
1
2
3
4
5
6
7
8
9
0.088 (2,23)
0.072 (1,83)
0.100 (2,54)
0.194 (4,93)
0.166 (4,22)
0.055 (1,39)
0.045 (1,14)
0.050 (1,27) DIA
4 Places
0.018 (0,46) DIA TYP
4040114-14 / A 2/95
NOTES: A.
B.
C.
D.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
Index mark may appear on top or bottom depending on package vendor.
Pins are located within 0.005 (0,13) radius of true position relative to each other at maximum material condition and within
0.015 (0,38) radius relative to the center of the ceramic.
E. This package can be hermetically sealed with metal lids or with ceramic lids using glass frit.
F. The pins can be gold plated or solder dipped.
G. Falls within MIL-STD-1835 CMGA1-PN and CMGA13-PN and JEDEC MO-067AA and MO-066AA, respectively
POST OFFICE BOX 1443
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59
SMJ55166
262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
MECHANICAL DATA
HKC (R-CDFP-F64)
CERAMIC DUAL FLATPACK WITH TIE BAR
1.620 (41,14)
SQ
1.580 (40,13)
1.020 (25,91)
0.980 (24,89)
0.765 (19,43)
0.730 (18,54)
0.026 (0,66) MIN
0.150 (3,81)
0.100 (2,54)
33
0.070 (1,78)
0.055 (1,40)
64
0.445 (11,30)
0.420 (10,67)
1
32
0.320 (8,13)
0.295 (7,49)
0.0098 (0,250)
0.0060 (0,150)
0.185 (4,70)
0.145 (3,68)
0.0079 (0,200)
0.0043 (0,110)
0.0196 (0,500)
0.040 (1,02)
0.030 (0,76)
4073160 / B 10/94
NOTES: A.
B.
C.
D.
E.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
This package can be hermetically sealed with a metal lid.
The terminals are gold plated.
All leads not shown for clarity purposes.
device symbolization
-SS
Speed (-70, - 80)
SMJ55166 HKC M
Temperature Range
Package Code
F
R
A
XXX LLL
Lot Traceability Code
Date Code
Assembly Site Code
Die Revision Code
Wafer Fab Code
60
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262144 BY 16-BIT
MULTIPORT VIDEO RAM
SGMS057C – APRIL 1995 – REVISED JUNE 1997
POST OFFICE BOX 1443
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61
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