TI SN74ACT7805-20DL

SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
D
D
D
D
D
D
D
D
D
D
D
D
D
Member of the Texas Instruments
Widebus Family
Free-Running Read and Write Clocks Can
Be Asynchronous or Coincident
Read and Write Operations Synchronized
to Independent System Clocks
Input-Ready Flag Synchronized to Write
Clock
Output-Ready Flag Synchronized to Read
Clock
256 Words by 18 Bits
Low-Power Advanced CMOS Technology
Half-Full Flag and Programmable
Almost-Full/Almost-Empty Flag
Bidirectional Configuration and Width
Expansion Without Additional Logic
Fast Access Times of 12 ns With a 50-pF
Load and All Data Outputs Switching
Simultaneously
Data Rates up to 67 MHz
Pin-to-Pin Compatible With SN74ACT7803
and SN74ACT7813
Packaged in Shrink Small-Outline 300-mil
Package Using 25-mil Center-to-Center
Spacing
description
DL PACKAGE
(TOP VIEW)
RESET
D17
D16
D15
D14
D13
D12
D11
D10
VCC
D9
D8
GND
D7
D6
D5
D4
D3
D2
D1
D0
HF
PEN
AF/AE
WRTCLK
WRTEN2
WRTEN1
IR
1
56
2
55
3
54
4
53
5
52
6
51
7
50
8
49
9
48
10
47
11
46
12
45
13
44
14
43
15
42
16
41
17
40
18
39
19
38
20
37
21
36
22
35
23
34
24
33
25
32
26
31
27
30
OE1
Q17
Q16
Q15
GND
Q14
VCC
Q13
Q12
Q11
Q10
Q9
GND
Q8
Q7
Q6
Q5
VCC
Q4
Q3
Q2
GND
Q1
Q0
RDCLK
RDEN
OE2
OR
28
29
The SN74ACT7805 is a 256-word × 18-bit clocked
FIFO suited for buffering asynchronous data
paths up to 67-MHz clock rates and 12-ns access
times. Two devices can be configured for bidirectional data buffering without additional logic. Multiple distributed
VCC and GND pins, along with Texas Instruments patented output edge control (OEC) circuit, dampen
simultaneous switching noise.
The write clock (WRTCLK) and read clock (RDCLK) are free running and can be asynchronous or coincident.
Data is written to memory on the rising edge of WRTCLK when WRTEN1 is high, WRTEN2 is low, and IR is high.
Data is read from memory on the rising edge of RDCLK when RDEN, OE1, and OE2 are low and OR is high.
The first word written to memory is clocked through to the output buffer, regardless of the RDEN, OE1, and OE2
levels. The OR flag indicates that valid data is present on the output buffer.
The FIFO can be reset asynchronously to WRTCLK and RDCLK. RESET must be asserted while at least four
WRTCLK and four RDCLK rising edges occur to clear the synchronizing registers. Resetting the FIFO initializes
the input-ready (IR), output-ready (OR), and half-full (HF) flags low and the almost-full/almost-empty (AF/AE)
flag high. The FIFO must be reset upon power up.
The SN74ACT7805 is characterized for operation from 0°C to 70°C.
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.
Widebus and OEC are trademarks of Texas Instruments Incorporated.
Copyright  1998, 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.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
1
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
logic symbol†
1
RESET
WRTCLK
WRTEN1
Φ
FIFO 256 × 18
SN74ACT7805
RESET
25
WRTCLK
27
&
WRTEN
26
WRTEN2
RDCLK
IN RDY
32
RDCLK
HALF-FULL
56
OE1
&
30
EN1
ALMOST FULL/EMPTY
OE2
OUT RDY
28
22
24
29
IR
HF
AF/AE
OR
&
RDEN
31
RDEN
PEN
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
D14
D15
D16
D17
23
21
PROGRAM ENABLE
0
0
34
19
36
18
37
17
38
16
40
15
41
14
42
12
43
11
45
Data
Data
1
9
46
8
47
7
48
6
49
5
51
4
53
3
54
2
55
17
17
† This symbol is in accordance with ANSI/IEEE Std 91-1984 and IEC Publication 617-12.
2
33
20
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Q0
Q1
Q2
Q3
Q4
Q5
Q6
Q7
Q8
Q9
Q10
Q11
Q12
Q13
Q14
Q15
Q16
Q17
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
functional block diagram
OE1
OE2
Output
Control
D0–D17
Location 1
RDCLK
RDEN
Synchronous
Read
Control
Location 2
Read
Pointer
256 × 18 RAM
WRTCLK
WRTEN1
WRTEN2
Synchronous
Write
Control
Write
Pointer
Location 255
Location 256
Register
RESET
StatusFlag
Logic
Reset
Logic
Q0–Q17
OR
IR
HF
AF/AE
PEN
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3
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
Terminal Functions
TERMINAL
I/O
DESCRIPTION
24
O
Almost-full/almost-empty flag. Depth offset values can be programmed for AF/AE, or the default
value of 32 can be used for both the almost-empty offset (X) and the almost-full offset (Y). AF/AE is
high when memory contains X or fewer words or (256 – Y) or more words. AF/AE is high after reset.
21–14, 12–11,
9–2
I
18-bit data input port
HF
22
O
Half-full flag. HF is high when the FIFO memory contains 128 or more words. HF is low after reset.
IR
28
O
Input-ready flag. IR is synchronized to the low-to-high transition of WRTCLK. When IR is low, the
FIFO is full and writes are disabled. IR is low during reset and goes high on the second low-to-high
transition of WRTCLK after reset.
56, 30
I
Output enables. When OE1, OE2, and RDEN are low and OR is high, data is read from the FIFO on
a low-to-high transition of RDCLK. When either OE1 or OE2 is high, reads are disabled and the data
outputs are in the high-impedance state.
NAME
AF/AE
D0–D17
OE1, OE2
4
NO.
OR
29
O
Output-ready flag. OR is synchronized to the low-to-high transition of RDCLK. When OR is low, the
FIFO is empty and reads are disabled. Ready data is present on Q0–Q17 when OR is high. OR is
low during reset and goes high on the third low-to-high transition of RDCLK after the first word is
loaded to empty memory.
PEN
23
I
Program enable. After reset and before the first word is written to the FIFO, the binary value on D0–D6
is latched as an AF/AE offset value when PEN is low and WRTCLK is high.
Q0–Q17
33–34, 36–38,
40–43, 45–49,
51, 53–55
O
18-bit data output port. After the first valid write to empty memory, the first word is output on Q0–Q17
on the third rising edge of RDCLK. OR also is asserted high at this time to indicate ready data. When
OR is low, the last word read from the FIFO is present on Q0–Q17.
RDCLK
32
I
Read clock. RDCLK is a continuous clock and can be asynchronous or coincident to WRTCLK. A
low-to-high transition of RDCLK reads data from memory when OE1, OE2, and RDEN are low and
OR is high. OR is synchronous to the low-to-high transition or RDCLK.
RDEN
31
I
Read enable. When RDEN, OE1, and OE2 are low and OR is high, data is read from the FIFO on
the low-to-high transition of RDCLK.
RESET
1
I
Reset. To reset the FIFO, four low-to-high transitions of RDCLK and four low-to-high transitions of
WRTCLK must occur while RESET is low. This sets HF, IR, and OR low and AF/AE high.
WRTCLK
25
I
Write clock. WRTCLK is a continuous clock and can be asynchronous or coincident to RDCLK. A
low-to-high transition of WRTCLK writes data to memory when WRTEN2 is low, WRTEN1 is high,
and IR is high. IR is synchronous to the low-to-high transition of WRTCLK.
WRTEN1,
WRTEN2
27, 26
I
Write enables. When WRTEN1 is high, WRTEN2 is low, and IR is high, data is written to the FIFO
on a low-to-high transition of WRTCLK.
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
RESET
1
0
PEN
1
WRTCLK
2
3
4
1
2
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
WRTEN1
Don’t Care
WRTEN2
Don’t Care
Don’t Care
D0–D17
1
RDCLK
2
3
4
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎ
OE1
Don’t Care
RDEN
Don’t Care
OE2
Don’t Care
Q0–Q17
Invalid
OR
Don’t Care
AF/AE
Don’t Care
HF
Don’t Care
IR
Don’t Care
Define the AF/AE Flag Using the
Default Value of X = Y = 32
Figure 1. Reset Cycle
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5
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
RESET
1
0
PEN
1
0
WRTCLK
1
0
WRTEN1
WRTEN2
D0–D17
RDCLK
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
W1
W2
W3
W4
1
2
3
W(X+2)
W129
W257
OE1
1
0
RDEN
1
0
OE2
1
0
Q0–Q17
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
Invalid
W1
OR
AF/AE
HF
IR
Figure 2. Write
6
W(257–Y)
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
1
0
RESET
1
PEN
0
WRTCLK
1
2
WRTEN1
WRTEN2
D0–D17
1
0
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
W257
RDCLK
1
0
OE1
RDEN
OE2
Q0–Q17
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉÉ
W1
W2
W3
W(Y+1)
W(Y+2)
W129
W130
W(256–X)
W(257–X)
W256
W257
OR
AF/AE
HF
IR
Figure 3. Read
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7
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
offset values for AF/AE
The AF/AE flag has two programmable limits: the almost-empty offset value (X) and the almost-full offset
value (Y). They can be programmed after the FIFO is reset and before the first word is written to memory. If the
offsets are not programmed, the default values of X = Y = 32 are used. The AF/AE flag is high when the FIFO
contains X or fewer words or (256 – Y) or more words.
Program enable (PEN) should be held high throughout the reset cycle. PEN can be brought low only when IR
is high and WRTCLK is low. On the following low-to-high transition of WRTCLK, the binary value on D0–D6 is
stored as the almost-empty offset value (X) and the almost-full offset value (Y). Holding PEN low for another
low-to-high transition of WRTCLK reprograms Y to the binary value on D0–D6 at the time of the second
WRTCLK low-to-high transition. When the offsets are being programmed, writes to the FIFO memory are
disabled regardless of the state of the write enables (WRTEN1, WRTEN2). A maximum value of 127 can be
programmed for either X or Y (see Figure 4). To use the default values of X = Y = 32, PEN must be held high.
RESET
3
4
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎ
ÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎ
ÎÎ
ÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎÎ
WRTCLK
PEN
D0–D6
X and Y
Y
IR
WRTEN1
WRTEN2
Figure 4. Programming X and Y Separately
absolute maximum ratings over operating free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V
Input voltage range, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 7 V
Voltage range applied to a disabled 3-state output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to 5.5 V
Package thermal impedance, θJA (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74°C/W
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: The package thermal impedance is calculated in accordance with JESD 51.
8
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
recommended operating conditions
’ACT7805-15
VCC
VIH
Supply voltage
VIL
IOH
Low-level input voltage
IOL
Low level output current
Low-level
TA
Operating free-air temperature
High-level input voltage
High-level output current
’ACT7805-20
’ACT7805-25
’ACT7805-40
MIN
MAX
MIN
MAX
MIN
MAX
MIN
MAX
4.5
5.5
4.5
5.5
4.5
5.5
4.5
5.5
2
2
2
2
UNIT
V
V
0.8
0.8
0.8
0.8
V
Q outputs, flags
–8
–8
–8
–8
mA
Q outputs
16
16
16
16
8
8
8
8
Flags
0
70
0
70
0
70
0
70
mA
°C
electrical characteristics over recommended operating free-air temperature range (unless
otherwise noted)
PARAMETER
VOH
VOL
II
IOZ
ICC
∆ICC‡
Ci
Flags
Q outputs
TEST CONDITIONS
VCC = 4.5 V,
VCC = 4.5 V,
IOH = –8 mA
IOL = 8 mA
VCC = 4.5 V,
VCC = 5.5 V,
IOL = 16 mA
VI = VCC or 0
MIN
TYP†
One input at 3.4 V,
UNIT
V
0.5
0.5
VCC = 5.5 V,
VO = VCC or 0
VI = VCC – 0.2 V or 0
VCC = 5.5 V,
VI = 0,
MAX
2.4
Other inputs at VCC or GND
V
±5
µA
±5
µA
400
µA
1
mA
f = 1 MHz
4
pF
VO = 0,
f = 1 MHz
† All typical values are at VCC = 5 V, TA = 25°C.
‡ This is the supply current for each input that is at one of the specified TTL voltage levels rather than 0 V or VCC.
8
pF
Co
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9
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
timing requirements over recommended operating conditions (unless otherwise noted) (see
Figures 1 through 5)
’ACT7805-15
MIN
fclock
tw
Clock frequency
Pulse duration
tsu
Setup time
Setu
th
Hold time
MAX
’ACT7805-20
MIN
67
MAX
’ACT7805-25
MIN
50
MAX
’ACT7805-40
MIN
40
MAX
25
WRTCLK high or low
6
7
8
12
RDCLK high or low
6
7
8
12
PEN low
8
9
9
12
D0–D17 before WRTCLK↑
4
5
5
5
WRTEN1, WRTEN2
before WRTCLK↑
4
5
5
5
OE1, OE2 before RDCLK↑
5
5
6
6
RDEN before RDCLK↑
4
5
5
5
Reset: RESET low before first
WRTCLK↑ and RDCLK↑†
5
6
6
6
PEN before WRTCLK↑
5
6
6
6
Define AF/AE: PEN
before WRTCLK↑
5
6
6
6
D0–D17) after WRTCLK↑
0
0
0
0
WRTEN1, WRTEN2
after WRTCLK↑
0
0
0
0
OE1, OE2, RDEN after RDCLK↑
0
0
0
0
Reset: RESET low after fourth
WRTCLK↑ and RDCLK↑†
2
2
2
2
Define AF/AE: PEN
after WRTCLK↑
2
2
2
2
UNIT
MHz
ns
ns
ns
† To permit the clock pulse to be utilized for reset purposes
switching characteristics over recommended ranges of supply voltage and operating free-air
temperature, CL = 50 pF (unless otherwise noted) (see Figure 5)
PARAMETER
FROM
(INPUT)
fmax
WRTCLK or
RDCLK
tpd
tpd‡
tpd
d
TO
(OUTPUT)
RDCLK↑
Any Q
RDCLK↑
Any Q
’ACT7805-15
TYP†
MAX
’ACT7805-20
MIN
MIN
67
50
4
9.5
12
4
MAX
’ACT7805-25
MIN
MAX
40
13
4
’ACT7805-40
MIN
MAX
25
15
4
MHz
20
8.5
IR
3
8.5
3
11
3
13
3
15
RDCLK↑
OR
3
8.5
3
11
3
13
3
15
7
16.5
7
19
7
21
7
23
RDCLK↑
AF/AE
ns
ns
WRTCLK↑
WRTCLK↑
UNIT
ns
7
17
7
19
7
21
7
23
tPLH
tPHL
WRTCLK↑
HF
7
15
7
17
7
19
7
21
ns
RDCLK↑
HF
7
15.5
7
18
7
20
7
22
ns
tPLH
RESET low
AF/AE
2
9
2
11
2
13
2
15
ns
tPHL
RESET low
HF
2
10
2
12
2
14
2
16
ns
ten
OE1, OE2
Any Q
2
8.5
2
11
2
11
2
11
ns
tdis
Any Q
2
OE1, OE2
‡ This parameter is measured with a 30-pF load (see Figure 6).
9.5
2
11
2
14
2
14
ns
10
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• DALLAS, TEXAS 75265
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
operating characteristics, VCC = 5 V, TA = 25°C
PARAMETER
Cpd
TEST CONDITIONS
Power dissipation capacitance per FIFO channel
Outputs enabled
CL = 50 pF,
TYP
f = 5 MHz
53
UNIT
pF
PARAMETER MEASUREMENT INFORMATION
7V
PARAMETER
S1
ten
500 Ω
From Output
Under Test
Test
Point
CL = 50 pF
(see Note A)
tdis
500 Ω
S1
tPZH
tPZL
tPHZ
tPLZ
tPLH
tPHL
tpd
Open
Closed
Open
Closed
Open
Open
tw
LOAD CIRCUIT
3V
Input
0V
1.5 V
VOLTAGE WAVEFORMS
PULSE DURATION
0V
tsu
th
3V
Data
Input
1.5 V
1.5 V
0V
3V
Output
Control
VOLTAGE WAVEFORMS
SETUP AND HOLD TIMES
1.5 V
1.5 V
1.5 V
0V
tPZL
3V
1.5 V
0V
tPLH
1.5 V
1.5 V
tPZH
1.5 V
VOL
tPLZ
≈ 3.5 V
Output
Waveform 1
S1 at 7 V
tPHL
VOH
Output
1.5 V
3V
Timing
Input
Input
1.5 V
Output
Waveform 2
S1 at Open
VOL + 0.3 V
VOL
tPHZ
1.5 V
VOH
VOH – 0.3 V
≈0V
VOLTAGE WAVEFORMS
ENABLE AND DISABLE TIMES
VOLTAGE WAVEFORMS
PROPAGATION DELAY TIMES
NOTE A: CL includes probe and jig capacitance.
Figure 5. Load Circuit and Voltage Waveforms
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11
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
TYPICAL CHARACTERISTICS
PROPAGATION DELAY TIME
vs
LOAD CAPACITANCE
SUPPLY CURRENT
vs
CLOCK FREQUENCY
200
VCC = 5 V
TA = 25°C
RL = 500 Ω
TA = 75°C
CL = 0 pF
180
typ + 6
VCC = 5.5 V
160
I CC(f) – Supply Current – mA
t pd – Propagation Delay Time – ns
typ + 8
typ + 4
typ + 2
typ
VCC = 5 V
140
120
100
VCC = 4.5 V
80
60
40
20
0
typ – 2
0
50
100
150
200
250
300
0
20
30
Figure 6
Figure 7
POST OFFICE BOX 655303
40
50
fclock – Clock Frequency – MHz
CL – Load Capacitance – pF
12
10
• DALLAS, TEXAS 75265
60
70
SN74ACT7805
256 × 18 CLOCKED FIRST-IN, FIRST-OUT MEMORY
SCAS201B – MARCH 1991 – REVISED APRIL 1998
APPLICATION INFORMATION
SN74ACT7805
WRTCLK
RDCLK
CLOCK A
W/RA
WRTEN1
OE1
CSA
WRTEN2
RDEN
CLOCK B
W/RB
CSB
OE2
18
D0–D17
B0–B17
Q0–Q17
SN74ACT7805
RDCLK
WRTCLK
OE1
WRTEN1
RDEN
WRTEN2
OE2
18
A0–A17
Q0–Q17
D0–D17
Figure 8. Bidirectional Configuration
SN74ACT7805
WRTCLK
WRTCLK
RDCLK
WRTEN1
WRTEN1
RDEN
WRTEN2
WRTEN2
OE1
IR
RDCLK
OE1
OR
OE2
OE2
36
D0–D35
D0–D17
Q0–Q17
OR
IR
SN74ACT7805
WRTCLK
RDCLK
WRTEN1
RDEN
WRTEN2
OE1
IR
OR
OE2
36
D0–D17
Q0–Q17
Q0–Q35
Figure 9. Word-Width Expansion: 256 × 36 Bits
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13
PACKAGE OPTION ADDENDUM
www.ti.com
6-Dec-2006
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
1M7805-15DLG4
ACTIVE
SSOP
DL
56
20
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-15DL
ACTIVE
SSOP
DL
56
20
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-15DLR
ACTIVE
SSOP
DL
56
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-20DL
ACTIVE
SSOP
DL
56
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-20DLR
ACTIVE
SSOP
DL
56
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-25DL
ACTIVE
SSOP
DL
56
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-25DLR
ACTIVE
SSOP
DL
56
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-40DL
ACTIVE
SSOP
DL
56
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
SN74ACT7805-40DLR
ACTIVE
SSOP
DL
56
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
20
20
20
Lead/Ball Finish
MSL Peak Temp (3)
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 1
MECHANICAL DATA
MSSO001C – JANUARY 1995 – REVISED DECEMBER 2001
DL (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
48 PINS SHOWN
0.025 (0,635)
0.0135 (0,343)
0.008 (0,203)
48
0.005 (0,13) M
25
0.010 (0,25)
0.005 (0,13)
0.299 (7,59)
0.291 (7,39)
0.420 (10,67)
0.395 (10,03)
Gage Plane
0.010 (0,25)
1
0°–ā8°
24
0.040 (1,02)
A
0.020 (0,51)
Seating Plane
0.110 (2,79) MAX
0.004 (0,10)
0.008 (0,20) MIN
PINS **
28
48
56
A MAX
0.380
(9,65)
0.630
(16,00)
0.730
(18,54)
A MIN
0.370
(9,40)
0.620
(15,75)
0.720
(18,29)
DIM
4040048 / E 12/01
NOTES: A.
B.
C.
D.
All linear dimensions are in inches (millimeters).
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion not to exceed 0.006 (0,15).
Falls within JEDEC MO-118
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