3.3 VOLT HIGH-DENSITY SUPERSYNC™ II 36-BIT FIFO
1,024 x 36, 2,048 x 36
4,096 x 36, 8,192 x 36
16,384 x 36, 32,768 x 36
65,536 x36, 131,072 x 36
IDT72V3640, IDT72V3650
IDT72V3660, IDT72V3670
IDT72V3680, IDT72V3690
IDT72V36100, IDT72V36110
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
FEATURES:
•
•
•
•
•
•
Choose among the following memory organizations:
Commercial
IDT72V3640
1,024 x 36
IDT72V3650
2,048 x 36
IDT72V3660
4,096 x 36
IDT72V3670
8,192 x 36
IDT72V3680
16,384 x 36
IDT72V3690
32,768 x 36
IDT72V36100
65,536 x 36
IDT72V36110
131,072 x 36
133 MHz operation (7.5 ns read/write cycle time)
User selectable input and output port bus-sizing
- x36 in to x36 out
- x36 in to x18 out
- x36 in to x9 out
- x18 in to x36 out
- x9 in to x36 out
Big-Endian/Little-Endian user selectable byte representation
5V input tolerant
Fixed, low first word latency
Zero latency retransmit
Auto power down minimizes standby power consumption
Master Reset clears entire FIFO
Partial Reset clears data, but retains programmable settings
Empty, Full and Half-Full flags signal FIFO status
Programmable Almost-Empty and Almost-Full flags, each flag can
default to one of eight preselected offsets
Selectable synchronous/asynchronous timing modes for Almost-
Empty and Almost-Full flags
Program programmable flags by either serial or parallel means
Select IDT Standard timing (using
EF
and
FF
flags) or First Word
Fall Through timing (using
OR
and
IR
flags)
Output enable puts data outputs into high impedance state
Easily expandable in depth and width
Independent Read and Write Clocks (permit reading and writing
simultaneously)
Available in the 128-pin Thin Quad Flat Pack (TQFP)
High-performance submicron CMOS technology
Industrial temperature range (–40°C to +85°C) is available
°
°
FUNCTIONAL BLOCK DIAGRAM
D
0
-D
n
(x36, x18 or x9)
WEN
WCLK
LD SEN
INPUT REGISTER
OFFSET REGISTER
FF/IR
PAF
EF/OR
PAE
HF
FWFT/SI
PFM
FSEL0
FSEL1
WRITE CONTROL
LOGIC
FLAG
LOGIC
RAM ARRAY
1,024 x 36, 2,048 x 36
4,096 x 36, 8,192 x 36
16,384 x 36, 32,768 x 36
65,536 x 36, 131,072 x36
WRITE POINTER
READ POINTER
BE
IP
BM
IW
OW
MRS
PRS
CONTROL
LOGIC
BUS
CONFIGURATION
RESET
LOGIC
OUTPUT REGISTER
READ
CONTROL
LOGIC
RT
RM
RCLK
REN
OE
Q
0
-Q
n
(x36, x18 or x9)
4667 drw 01
The SuperSync II FIFO is a trademark and the IDT logo is a registered trademark of Integrated Device Technology, Inc.
COMMERCIAL AND INDUSTRIAL TEMPERATURE RANGES
1
©
2001 Integrated Device Technology, Inc.
APRIL 2001
DSC-4667/3
IDT72V3640/50/60/70/80/90/110 3.3V HIGH DENSITY SUPERSYNC II
TM
36-BIT FIFO
1,024 x 36, 2,048 x 36, 4,096 x 36, 8,192 x 36, 16,384 x 36, 32,768 x 36, 65,536 x 36, 131,072 x 36
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
DESCRIPTION:
The IDT72V3640/72V3650/72V3660/72V3670/72V3680/72V3690/
72V36100/72V36110 are exceptionally deep, high speed, CMOS First-In-
First-Out (FIFO) memories with clocked read and write controls and a flexible
Bus-Matching x36/x18/x9 data flow. These FIFOs offer several key user
benefits:
• Flexible x36/x18/x9 Bus-Matching on both read and write ports
• The period required by the retransmit operation is fixed and short.
• The first word data latency period, from the time the first word is written to an
empty FIFO to the time it can be read, is fixed and short.
• High density offerings up to 4 Mbit
Bus-Matching Sync FIFOs are particularly appropriate for network, video,
telecommunications, data communications and other applications that need to
buffer large amounts of data and match busses of unequal sizes.
Each FIFO has a data input port (D
n
) and a data output port (Q
n
), both of
which can assume either a 36-bit, 18-bit or a 9-bit width as determined by the
state of external control pins Input Width (IW), Output Width (OW), and Bus-
Matching (BM) pin during the Master Reset cycle.
The input port is controlled by a Write Clock (WCLK) input and a Write Enable
(WEN) input. Data is written into the FIFO on every rising edge of WCLK when
WEN
is asserted. The output port is controlled by a Read Clock (RCLK) input
and Read Enable (REN) input. Data is read from the FIFO on every rising edge
PIN CONFIGURATIONS
INDEX
128
127
126
125
124
123
122
121
120
119
118
117
116
115
114
113
112
111
110
109
108
107
106
105
104
103
WCLK
PRS
MRS
LD
FWFT/SI
FF/IR
V
CC
PAF
GND
OW
FS0
HF
GND
FS1
BE
IP
BM
V
CC
PAE
PFM
EF/OR
RM
GND
RCLK
REN
RT
WEN
SEN
DNC
(1)
V
CC
DNC
(1)
IW
D35
D34
D33
D32
V
CC
D31
D30
GND
D29
D28
D27
D26
D25
D24
D23
GND
D22
V
CC
D21
D20
D19
D18
GND
D17
D16
D15
D14
D13
V
CC
D12
GND
D11
D10
D9
D8
D7
D6
GND
D5
D4
D3
V
CC
D2
D1
D0
GND
Q0
Q1
Q2
Q3
Q4
Q5
GND
Q6
V
CC
Q7
Q8
Q9
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
39
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
33
34
35
36
37
38
102
101
100
99
98
97
96
95
94
93
92
91
90
89
88
87
86
85
84
83
82
81
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
OE
V
CC
V
CC
Q35
Q34
Q33
Q32
GND
GND
Q31
Q30
Q29
Q28
Q27
Q26
V
CC
Q25
Q24
GND
GND
Q23
Q22
Q21
Q20
Q19
Q18
GND
Q17
Q16
V
CC
V
CC
Q15
Q14
Q13
Q12
GND
Q11
Q10
4667 drw 02
NOTE:
1. DNC = Do Not Connect.
TQFP (PK128-1, order code: PF)
TOP VIEW
2
IDT72V3640/50/60/70/80/90/110 3.3V HIGH DENSITY SUPERSYNC II
TM
36-BIT FIFO
1,024 x 36, 2,048 x 36, 4,096 x 36, 8,192 x 36, 16,384 x 36, 32,768 x 36, 65,536 x 36, 131,072 x 36
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
DESCRIPTION (CONTINUED)
of RCLK when
REN
is asserted. An Output Enable (OE) input is provided for
three-state control of the outputs.
The frequencies of both the RCLK and the WCLK signals may vary from 0
to f
MAX
with complete independence. There are no restrictions on the frequency
of the one clock input with respect to the other.
There are two possible timing modes of operation with these devices: IDT
Standard mode and First Word Fall Through (FWFT) mode.
In
IDT Standard mode,
the first word written to an empty FIFO will not appear
on the data output lines unless a specific read operation is performed. A read
operation, which consists of activating
REN
and enabling a rising RCLK edge,
will shift the word from internal memory to the data output lines.
In
FWFT mode,
the first word written to an empty FIFO is clocked directly
to the data output lines after three transitions of the RCLK signal. A
REN
does
not have to be asserted for accessing the first word. However, subsequent
words written to the FIFO do require a LOW on
REN
for access. The state of
the FWFT/SI input during Master Reset determines the timing mode in use.
For applications requiring more data storage capacity than a single FIFO
can provide, the FWFT timing mode permits depth expansion by chaining FIFOs
in series (i.e. the data outputs of one FIFO are connected to the corresponding
data inputs of the next). No external logic is required.
These FIFOs have five flag pins,
EF/OR
(Empty Flag or Output Ready),
FF/IR
(Full Flag or Input Ready),
HF
(Half-full Flag),
PAE
(Programmable
Almost-Empty flag) and
PAF
(Programmable Almost-Full flag). The
EF
and
FF
functions are selected in IDT Standard mode. The
IR
and
OR
functions are
selected in FWFT mode.
HF, PAE
and
PAF
are always available for use,
irrespective of timing mode.
PAE
and
PAF
can be programmed independently to switch at any point in
memory. Programmable offsets determine the flag switching threshold and can
be loaded by two methods: parallel or serial. Eight default offset settings are also
provided, so that
PAE
can be set to switch at a predefined number of locations
from the empty boundary and the
PAF
threshold can also be set at similar
predefined values from the full boundary. The default offset values are set during
Master Reset by the state of the FSEL0, FSEL1, and
LD
pins.
For serial programming,
SEN
together with
LD
on each rising edge of
WCLK, are used to load the offset registers via the Serial Input (SI). For parallel
programming,
WEN
together with
LD
on each rising edge of WCLK, are used
to load the offset registers via D
n
.
REN
together with
LD
on each rising edge
of RCLK can be used to read the offsets in parallel from Q
n
regardless of whether
serial or parallel offset loading has been selected.
During Master Reset (MRS) the following events occur: the read and write
pointers are set to the first location of the FIFO. The FWFT pin selects IDT
Standard mode or FWFT mode.
The Partial Reset (PRS) also sets the read and write pointers to the first
location of the memory. However, the timing mode, programmable flag
programming method, and default or programmed offset settings existing before
Partial Reset remain unchanged. The flags are updated according to the timing
mode and offsets in effect.
PRS
is useful for resetting a device in mid-operation,
when reprogramming programmable flags would be undesirable.
It is also possible to select the timing mode of the
PAE
(Programmable Almost-
Empty flag) and
PAF
(Programmable Almost-Full flag) outputs. The timing
modes can be set to be either asynchronous or synchronous for the
PAE
and
PAF
flags.
If asynchronous
PAE/PAF
configuration is selected, the
PAE
is asserted
LOW on the LOW-to-HIGH transition of RCLK.
PAE
is reset to HIGH on the LOW-
to-HIGH transition of WCLK. Similarly, the
PAF
is asserted LOW on the LOW-
to-HIGH transition of WCLK and
PAF
is reset to HIGH on the LOW-to-HIGH
transition of RCLK.
If synchronous
PAE/PAF
configuration is selected , the
PAE
is asserted and
updated on the rising edge of RCLK only and not WCLK. Similarly,
PAF
is
PARTIAL RESET (PRS)
WRITE CLOCK (WCLK)
WRITE ENABLE (WEN)
LOAD (LD)
(x36, x18, x9) DATA IN (D
0
- D
n
)
SERIAL ENABLE(SEN)
FIRST WORD FALL THROUGH/SERIAL INPUT
(FWFT/SI)
FULL FLAG/INPUT READY (FF/IR)
PROGRAMMABLE ALMOST-FULL (PAF)
MASTER RESET (MRS)
READ CLOCK (RCLK)
READ ENABLE (REN)
IDT
72V3640
72V3650
72V3660
72V3670
72V3680
72V3690
72V36100
72V36110
OUTPUT ENABLE (OE)
(x36, x18, x9) DATA OUT (Q
0
- Q
n
)
RETRANSMIT (RT)
EMPTY FLAG/OUTPUT READY (EF/OR)
PROGRAMMABLE ALMOST-EMPTY (PAE)
HALF-FULL FLAG (HF)
BIG-ENDIAN/LITTLE-ENDIAN (BE)
INTERSPERSED/
NON-INTERSPERSED PARITY (IP)
4667 drw 03
INPUT WIDTH (IW)
OUTPUT WIDTH (OW)
BUS-
MATCHING
(BM)
Figure 1. Single Device Configuration Signal Flow Diagram
3
IDT72V3640/50/60/70/80/90/110 3.3V HIGH DENSITY SUPERSYNC II
TM
36-BIT FIFO
1,024 x 36, 2,048 x 36, 4,096 x 36, 8,192 x 36, 16,384 x 36, 32,768 x 36, 65,536 x 36, 131,072 x 36
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
asserted and updated on the rising edge of WCLK only and not RCLK. The mode
desired is configured during MasterReset by the state of the Programmable Flag
Mode (PFM) pin.
The Retransmit function allows data to be reread from the FIFO more than
once. A LOW on the
RT
input during a rising RCLK edge initiates a retransmit
operation by setting the read pointer to the first location of the memory array.
A zero-latency retransmit timing mode can be selected using the Retransmit
timing Mode pin (RM). During Master Reset, a LOW on RM will select zero
latency retransmit. A HIGH on RM during Master Reset will select normal
latency.
If zero latency retransmit operation is selected, the first data word to be
retransmitted will be placed on the output register with respect to the same RCLK
edge that initiated the retransmit based on RT being LOW.
Refer to Figure 11 and 12 for
Retransmit Timing
with normal latency. Refer
to Figure 13 and 14 for
Zero Latency Retransmit Timing.
The device can be configured with different input and output bus widths as
shown in Table 1.
A Big-Endian/Little-Endian data word format is provided. This function is
useful when data is written into the FIFO in long word format (x36/x18) and read
out of the FIFO in small word (x18/x9) format. If Big-Endian mode is selected,
then the most significant byte (word) of the long word written into the FIFO will
be read out of the FIFO first, followed by the least significant byte. If Little-Endian
format is selected, then the least significant byte of the long word written into the
FIFO will be read out first, followed by the most significant byte. The mode desired
is configured during master reset by the state of the Big-Endian (BE) pin. See
Figure 4 for
Bus-Matching Byte Arrangement.
The Interspersed/Non-Interspersed Parity (IP) bit function allows the user
to select the parity bit in the word loaded into the parallel port (D
0
-Dn) when
programming the flag offsets. If Interspersed Parity mode is selected, then the
FIFO will assume that the parity bit is located in bit positions D8, D17, D26 and
D35 during the parallel programming of the flag offsets. If Non-Interspersed
Parity mode is selected, then D8, D17 and D26 are assumed to be valid bits
and D32, D33, D34 and D35 are ignored. IP mode is selected during Master
Reset by the state of the IP input pin. Interspersed Parity control only has an
effect during parallel programming of the offset registers. It does not effect the data
written to and read from the FIFO.
If, at any time, the FIFO is not actively performing an operation, the chip will
automatically power down. Once in the power down state, the standby supply
current consumption is minimized. Initiating any operation (by activating control
inputs) will immediately take the device out of the power down state.
The IDT72V3640/72V3650/72V3660/72V3670/72V3680/72V3690/
72V36100/72V36110 are fabricated using IDT’s high speed submicron CMOS
technology.
TABLE 1
BUS-MATCHING CONFIGURATION MODES
BM
L
H
H
H
H
NOTE:
1. Pin status during Master Reset.
IW
L
L
L
H
H
OW
L
L
H
L
H
Write Port Width
x36
x36
x36
x18
x9
Read Port Width
x36
x18
x9
x36
x36
4
IDT72V3640/50/60/70/80/90/110 3.3V HIGH DENSITY SUPERSYNC II
TM
36-BIT FIFO
1,024 x 36, 2,048 x 36, 4,096 x 36, 8,192 x 36, 16,384 x 36, 32,768 x 36, 65,536 x 36, 131,072 x 36
COMMERCIAL AND INDUSTRIAL
TEMPERATURE RANGES
PIN DESCRIPTION
I/O
Description
I
Data inputs for a 36-, 18- or 9-bit bus. When in 18- or 9-bit mode, the unused input pins are in a don’t care state.
I
MRS
initializes the read and write pointers to zero and sets the output register to all zeroes. During Master Reset, the
FIFO is configured for either FWFT or IDT Standard mode, Bus-Matching configurations, one of eight programmable
flag default settings, serial or parallel programming of the offset settings, Big-Endian/Little-Endian format, zero
latency timing mode, interspersed parity, and synchronous versus asynchronous programmable flag timing modes.
PRS
Partial Reset
I
PRS
initializes the read and write pointers to zero and sets the output register to all zeroes. During Partial Reset, the
existing mode (IDT or FWFT), programming method (serial or parallel), and programmable flag settings are all retained.
RT
Retransmit
I
RT
asserted on the rising edge of RCLK initializes the READ pointer to zero, sets the
EF
flag to LOW (OR to HIGH
in FWFT mode) and does not disturb the write pointer, programming method, existing timing mode or programmable
flag settings.
RT
is useful to reread data from the first physical location of the FIFO.
FWFT/SI First Word Fall
I
During Master Reset, selects First Word Fall Through or IDT Standard mode. After Master Reset, this pin
Through/Serial In
functions as a serial input for loading offset registers.
OW
(1)
Output Width
I
This pin, along with IW and BM, selects the bus width of the read port. See Table 1 for bus size configuration.
(1)
IW
Input Width
I
This pin, along with OW and MB, selects the bus width of the write port. See Table 1 for bus size configuration.
(1)
Bus-Matching
I
BM works with IW and OW to select the bus sizes for both write and read ports. See Table 1 for bus size configuration.
BM
BE
(1)
Big-Endian/
I
During Master Reset, a LOW on
BE
will select Big-Endian operation. A HIGH on
BE
during Master Reset
Little-Endian
will select Little-Endian format.
(1)
RM
Retransmit Timing I
During Master Reset, a LOW on RM will select zero latency Retransmit timing Mode. A HIGH on RM will select
Mode
normal latency mode.
PFM
(1)
Programmable
I
During Master Reset, a LOW on PFM will select Asynchronous Programmable flag timing mode. A HIGH on PFM
Flag Mode
will select Synchronous Programmable flag timing mode.
IP
(1)
Interspersed Parity I
During Master Reset, a LOW on IP will select Non-Interspersed Parity mode. A HIGH will select Interspersed Parity
mode. Interspersed Parity control only has an effect during parallel programming of the offset registers. It does not effect
the data written to and read from the FIFO.
I
During Master Reset, this input along with FSEL1 and the
LD
pin, will select the default offset values for the programmable
FSEL0
(1)
Flag Select Bit 0
flags
PAE
and
PAF.
There are up to eight possible settings available.
(1)
Flag Select Bit 1
I
During Master Reset, this input along with FSEL0 and the
LD
pin will select the default offset values for the programmable
FSEL1
flags
PAE
and
PAF.
There are up to eight possible settings available.
WCLK
Write Clock
I
When enabled by
WEN,
the rising edge of WCLK writes data into the FIFO and offsets into the programmable registers
for parallel programming, and when enabled by
SEN,
the rising edge of WCLK writes one bit of data into the
programmable register for serial programming.
WEN
Write Enable
I
WEN
enables WCLK for writing data into the FIFO memory and offset registers.
RCLK
Read Clock
I
When enabled by
REN,
the rising edge of RCLK reads data from the FIFO memory and offsets from the programmable
registers.
REN
Read Enable
I
REN
enables RCLK for reading data from the FIFO memory and offset registers.
OE
Output Enable
I
OE
controls the output impedance of Q
n.
SEN
Serial Enable
I
SEN
enables serial loading of programmable flag offsets.
LD
Load
I
This is a dual purpose pin. During Master Reset, the state of the
LD
input along with FSEL0 and FSEL1, determines
one of eight default offset values for the
PAE
and
PAF
flags, along with the method by which these offset registers can
be programmed, parallel or serial (see Table 2). After Master Reset, this pin enables writing to and reading from the
offset registers.
FF/IR
Full Flag/
O In the IDT Standard mode, the
FF
function is selected.
FF
indicates whether or Input Ready not the FIFO memory
is full. In the FWFT mode, the
IR
function is selected.
IR
indicates whether or not there is space available for writing
to the FIFO memory.
EF/OR
Empty Flag/
O In the IDT Standard mode, the
EF
function is selected.
EF
indicates whether or not the FIFO memory is empty.
Output Ready
In FWFT mode, the
OR
function is selected.
OR
indicates whether or not there is valid data available at the outputs.
PAF
Programmable
O
PAF
goes HIGH if the number of free locations in the FIFO memory is more than offset m, which is stored in the
Almost-Full Flag
Full Offset register.
PAF
goes LOW if the number of free locations in the FIFO memory is less than or equal to m.
PAE
Programmable
O
PAE
goes LOW if the number of words in the FIFO memory is less than offset n, which is stored in the Empty Offset
Almost-Empty Flag
register.
PAE
goes HIGH if the number of words in the FIFO memory is greater than or equal to offset n.
HF
Half-Full Flag
O
HF
indicates whether the FIFO memory is more or less than half-full.
O Data outputs for an 36-, 18- or 9-bit bus. When in 18- or 9-bit mode, the unused output pins are in a don’t care
Q
0
–Q
35
Data Outputs
state. Outputs are not 5V tolerant regardless of the state of
OE.
NOTE:
1. Inputs should not change state after Master Reset.
Symbol
D
0
–D
35
MRS
Name
Data Inputs
Master Reset
5
京公网安备 11010802033920号
EEWORLD
