IDT IDT72104L35J

IDT72103
IDT72104
CMOS PARALLEL-SERIAL FIFO
2048 x 9, 4096 x 9
Integrated Device Technology, Inc.
FEATURES:
APPLICATIONS:
• 35ns parallel port access time, 45ns cycle time
• 50MHz serial input/output frequency
• Serial-to-parallel, parallel-to-serial, serial-to-serial, and
parallel-to-parallel operations
• Expandable in both depth and width with no external
components
• Flexishift — Sets programmable serial word width
from 4 bits to any width with no external components
• Multiple flags: Full, Almost-Full (Full-1/8),Full-MinusOne, Empty, Almost-Empty (Empty + 1/8), Empty-Plus
One, and Half-Full
• Asynchronous and simultaneous read or write
operations
• Dual-Port, zero fall-through time architecture
• Retransmit capability in single-device mode
• Packaged in 44-pin PLCC
• Industrial temperature range (-40oC to +85oC) is available, tested to military electrical specifications
•
•
•
•
•
•
•
•
•
High-speed data acquisition systems
Local area network (LAN) buffer
High-speed modem data buffer
Remote telemetry data buffer
FAX raster video data buffer
Laser printer engine data buffer
High-speed parallel bus-to-bus communications
Magnetic media controllers
Serial link buffer
DESCRIPTION:
The IDT72103/72104 are high-speed Parallel-Serial FlFOs
to be used with high-performance systems for functions such
as serial communications, laser printer engine control and
local area networks.
A serial input, a serial output and two 9-bit parallel ports
make four modes of data transfer possible: serial-to-parallel,
parallel-to-serial, serial-to-serial, and parallel-to-parallel. The
IDT72103/72104 are expandable in both depth and width for
all of these operational configurations.
FUNCTIONAL BLOCK DIAGRAM
SERIAL
INPUT
SI
SIX
SICP
DATA INPUTS (D 0 -D 8 )
SERIAL
INPUT
CIRCUITRY
FLAG
LOGIC
SI/PI
SO/PO
SERIAL/
PARALLEL
CONTROL
W
WRITE
POINTER
XI
XO
FL/RT
RAM ARRAY
2048 x 9
4096 x 9
READ
POINTER
RESET
LOGIC
DEPTH
EXPANSION
LOGIC
SERIAL
OUTPUT
CIRCUITRY
OE
DATA OUTPUTS (Q 0 -Q 8 )
FF
FF-1
EF+1
EF
AEF
HF
R
RS
SERIAL
OUTPUT
SO
SOX
SOCP
2753 drw 01
The IDT logo is a registered trademark of Integrated Device Technology,Inc.
COMMERCIAL TEMPERATURE RANGES
1996 Integrated Device Technology, Inc.
DECEMBER 1996
For latest information contact IDT's web site at www.idt.com or fax-on-demand at 408-492-8391.
5.37
DSC-2753/8
1
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
DESCRIPTION (CONTINUED)
The IDT72103/72104 may be configured to handle serial
word widths of four or greater using IDT’s unique Flexishift
feature. Flexishift allows serial width and depth expansion
without external components. For example, you may configure a 4K x 24 FIFO using three IDT72104s in a serial width
expansion configuration.
Seven flags are provided to signal memory status of the
FIFO. The flags are FF (Full), AF (7/8 full), FF–1 (Full-minusone), EF (Empty), AE (1/8 full), EF+1 (Empty-plus-one), and
HF (Half-full).
Read (R) and Write (W) control pins are provided for
asynchronous and simultaneous operations. An output enable (OE) control pin is available on the parallel output port for
high-impedance control. The depth expansion control pins XO
and Xl are provided to allow cascading for deeper FlFOs.
The IDT72103/72104 are manufactured using IDT’s CMOS
technology.
GND
D1
D2
D3
D4
W
VCC
D5
D6
D7
D8
PIN CONFIGURATIONS
INDEX
6
7
5
4
3
2
1
44 43 42 41 40
39
8
9
38
37
10
11
36
35
J44-1
12
13
34
33
14
32
15
31
16
30
17
29
18 19 20 21 22 23 24 25 26 27 28
Q1
Q2
Q3
Q4
GND
R
Q5
Q6
Q7
Q8
GND
D0
XI
SO/PO
SOX
SOCP
SO
AEF
FF-1
FF
Q0
GND
GND
FL/RT
RS
SI
SICP
SIX
SI/PI
OE
EF+1
EF
XO/HF
2753 drw 03
PLCC
TOP VIEW
5.37
2
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
ABSOLUTE MAXIMUM RATINGS(1)
CAPACITANCE (TA = +25°C, f = 1.0MHz)
Symbol
Rating
Commercial
Unit
VTERM
Terminal Voltage
with Respect to GND
Operating Temperature
Temperature Under Bias
Storage Temperature
DC Output Current
–0.5 to +7.0
V
0 to +70
–55 to +125
–55 to +125
50
°C
°C
°C
mA
TA
TBIAS
TSTG
IOUT
Symbol
Parameter(1)
Conditions
Max.
Unit
pF
CIN
Input Capacitance
VIN = 0V
10
COUT
Output Capacitance
VOUT = 0V
12
pF
NOTE:
1. This parameter is sampled and not 100% tested.
2753 tbl 01
2753 tbl 02
RECOMMENDED DC OPERATING CONDITIONS
Symbol
NOTE:
1. Stresses greater than those listed under ABSOLUTE MAXIMUM
RATINGS may cause permanent damage to the device. This is a stress
rating only and functional operation of the device at these or any other
conditions above those indicated in the operational sections of this
specification is not implied. Exposure to absolute maximum rating
conditions for extended periods may affect reliability.
Parameter
Min.
Typ.
Max. Unit
4.5
5.0
5.5
V
0
0
0
V
VCCC
Commercial Supply
Voltage
GND
Supply Voltage
VIH
Input High Voltage
Commercial
2.0
—
—
V
VIL(1)
Input Low Voltage
—
—
0.8
V
NOTE:
1. 1.5V undershoots are allowed for 10ns once per cycle.
2753 tbl 03
PIN DESCRIPTION
Symbol
D0-D8
Name
Data Inputs
Serial Input Word
Width Select
I/O
I/O
RS
Reset
I
W
Write
I
R
Read
I
First Load/
Retransmit
I
Xl
Expansion In
I
OE
Output Enable
I
O
FF
Data Outputs /
Serial Output
Word Width Select
Full Flag
O
FF-1
Full-1 Flag
O
FL/RT
Q0-Q8
Description
In a parallel input configuration – data inputs for 9-bit wide data.
In a serial input configuration – one of the nine output pins is used to select the serial input
word width.
When RS is set low, internal READ and WRITE pointers are set to the first location of the RAM
array. EF, EF+1, AEF are all LOW after a reset, while FF, FF-1, HF are HIGH after a reset.
A parallel word write cycle is initiated on the falling edge of W if the FF is high. When the FIFO
is full, FF will go low inhibiting further write operations to prevent data overflow. In a serial
input configuration, data bits are clocked into the input shift register and the write pointer does
not advance until a full parallel word is assembled. One of the pins, Di, is connected to W and
advances the write pointer every i-th serial input clock.
A read cycle is initiated on the falling edge of R if the EF is HIGH. After all the data from the
FIFO has been read EF will go LOW inhibiting further read operations. In a serial output
configuration, a data word is read from memory into the output shift register. One of the pins,
Qj, is connected to R and advances the read pointer every j-th serial output clock.
This is a dual-purpose pin. In multiple-device mode, FL/RT is grounded to indicate the first
device loaded. In single-device mode, FL/RT acts as the retransmit input. Single-device mode
is initiated by grounding the XI pin.
In single-device mode, XI is grounded.In depth expansion or daisy chain mode, XI is con
nected to the XO pin of the previous device.
When OE is LOW, both parallel and serial outputs are enabled. When OE is HIGH, the parallel
output buffers are placed in a high-impedance state.
In a parallel output configuration - data outputs for 9-bit wide data. In a serial output
configuration - one of nine output pins used to select the serial output word width.
FF is asserted LOW when the FIFO is full and further write operations are inhibited. When
the FF is HIGH, the FIFO is not full and data can be written into the FIFO.
FF-1 goes LOW when the FIFO memory array is one word away from being full. It will remain
LOW when every memory location is filled.
2753 tbl 04
5.37
3
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
PIN DESCRIPTION (Continued)
Symbol
XO/HF
Name
Expansion Out/
Half-Full Flag
I/O
O
Description
HF is LOW when the FIFO is more than half-full in the single device or width expansion
modes. The HF will remain LOW until the difference between the write and read pointers is
less than or equal to one-half of the FIFO memory.
In depth expansion mode, a pulse is written from XO to XI of the next device when the last
location in the FIFO is filled. Another pulse is sent from XO to Xl of the next device when the
last FIFO location is read.
AEF
When AEF is LOW, the FIFO is empty to 1/8 full or 7/8 full to completely full. If
then the FIFO is greater than 1/8 full, but less than 7/8 full.
AEF is HIGH,
Almost-Empty/
Almost-Full Flag
O
Empty+1 Flag
O
Empty Flag
O
EF+ 1 is LOW when there is zero or one word word in the FIFO memory array.
EF goes LOW when the FIFO is empty and further read operations are inhibited. FF is HIGH
Sl
Serial Input
I
Data input for serial data.
SO
Serial Output
O
Data output for serial data.
SICP
Serial Input Clock
I
This pin is the serial input clock. On the rising edge of the SICP signal, new serial data bits
are read into the serial input shift register.
SOCP
Serial Output
Clock
I
This pin is the serial output clock. On the rising edge of the SOCP signal, new serial data bits
are read from the serial output shift register.
SIX
Serial Input
Expansion
I
SIX controls the serial input expansion for word widths greater than 9 bits. In a serial input
configuration, the SIX pin of the least significant device is tied HIGH. The SIX pin of all other
devices is connected to the D8 pin of the previous device. In parallel input configurations or
serial input configurations of 9 bits or less, SIX is tied HIGH.
SOX
Serial Output
Expansion
I
SOX controls the serial output expansion for word widths greater than 9 bits. In a serial output
configuration, the SOX pin of the least significant device is tied HIGH. The SOX pin of all other
devices is connected to the Q8 pin of the previous device. In parallel output configurations
or serial output configurations of 9 bits or less, SOX is tied HIGH.
SI/PI
Serial/Parallel Input
I
When this pin is HIGH, the FIFO is in a parallel input configuration and accepts input data
through D0-D8. When SI/PI is LOW, the FIFO is in a serial input configuration and data is input
through Sl.
SO/PO
Serial/Parallel Output
I
When this pin is HIGH, the FIFO is in a parallel output configuration and sends output data
through Q0-Q8. When SO/PO is LOW the FIFO is in a serial output configuration and data
is input through SO.
GND
Ground
One ground pin for the DIP package and five ground pins for the LCC/PLCC packages.
VCC
Power
One + 5V power pin.
EF+1
EF
when the FIFO is not empty and data reads are permitted.
2753 tbl 05
5.37
4
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
DC ELECTRICAL CHARACTERISTICS
(Commercial: VCC = 5.0V ± 10%, TA = 0°C to +70°C)
IDT72103/72104
Commercial
tA = 35, 50ns
Symbol
Min.
Typ.
Max.
Unit
IIL(1)
Input Leakage Current
(Any Input)
–1
—
1
µA
IOL(2)
Output Leakage Current
–10
—
10
µA
VOH
Output Logic "1" Voltage,
IOUT = -2mA(4)
2.4
—
—
V
VOL
Output Logic "0" Voltage,
IOUT = 8mA(5)
—
—
0.4
V
ICC1(3)
Average VCC Power Supply Current
—
90
140
mA
I
Average Standby Current
(R = W = RS = FL/RT = VIH)
(SOCP = SICP = VIL)
—
8
12
mA
ICC3(L)(3,6)
Power Down Current
—
—
2
(3)
CC2
Parameter
mA
NOTES:
1. Measurements with 0.4 ≤ VIN ≤ VCC.
2. R ≥ VIH, SOCP ≤ VIL, 0.4 ≤ VOUT ≤ VCC.
3. ICC measurements are made with outputs open.
4. For SO, IOUT = -8mA.
5. For SO, IOUT =16mA.
6. SOCP = SICP ≤ 0.2V; other Inputs = VCC -0.2V.
2753 tbl 06
AC TEST CONDITIONS
Input Pulse Levels
Input Rise/Fall Times
3ns
Input Timing Reference Levels
1.5V
Output Reference Levels
1.5V
Output Load
5V
GND to 3.0V
1.1KΩ
See Figure 1
2753 tbl 07
D.U.T.
680Ω
30pF*
2753 drw 04
or equivalent circuit
Figure 1. Ouput Load
*Including jig and scope capacitances
5.37
5
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
AC ELECTRICAL CHARACTERISTICS
(Commercial: VCC = 5.0V ± 10%, TA = 0°C to +70°C)
Symbol
Parameter
fS
Parallel Shift Frequency
fSOCP
Serial-Out Shift Frequency
fSICP
Serial-In Shift Frequency
PARALLEL-OUTPUT MODE TIMINGS
tA
Access Time
tRR
Read Recovery Time
tRPW
Read Pulse Width
tRC
Read Cycle Time
tWLZ
Write Pulse LOW to Data Bus at Low-Z(1)
tRLZ
Read Pulse LOW to Data Bus at Low-Z(1)
tRHZ
Read Pulse HIGH to Data Bus at High-Z(1)
tDV
Data Valid from Read Pulse HIGH
PARALLEL-INPUT MODE TIMINGS
tDS
Data Set-up Time
tDH
Data Hold Time
tWC
Write Cycle Time
tWPW
Write Pulse Width
tWR
Write Recovery Time
RESET TIMINGS
tRSC
Reset Cycle Time
tRS
Reset Pulse Width
tRSS
Reset Set-up Time
tRSR
Reset Recovery Time
RESET TO FLAG TIMINGS
tRSF1
Reset to EF, AEF, and EF+1 LOW
tRSF2
Reset to HF, FF, and FF-1 LOW
RESET TO OUTPUT TIMINGS – SERIAL MODE ONLY
tRSQL
Reset Going LOW to Q0-8 LOW
tRSQH
Reset Going HIGH to Q0-8 HIGH
tRSDL
Reset Going LOW to D0-8 LOW
RETRANSMIT TIMINGS
tRTC
Retransmit Cycle Time
tRT
Retransmit Pulse Width
tRTS
Retransmit Set-up Time
tRTR
Retransmit Recovery Time
tRTF
Retransmit to Flags
PARALLEL MODE FLAG TIMINGS
tREF
Read LOW to EF LOW
tRFF
Read HIGH to FF HIGH
tRF
Read HIGH to Transitioning HF, AEF and FF-1
tRE
Read LOW to EF+1 LOW
tRPE
Read Pulse Width after EF HIGH
tWEF
Write HIGH to EF HIGH
tWFF
Write LOW to FF LOW
tWF
Write LOW to Transitioning HF, AEF and FF-1
tWE
Write HIGH to EF+1 HIGH
tWPF
Write Pulse Width after FF HIGH
Commercial
IDT72103L35
IDT72103L50
IDT72104L35
IDT72104L50
Min.
Max.
Min.
Max.
—
22.2
—
15
—
50
—
40
—
50
—
40
Unit
MHz
MHz
MHz
Timing
Figure
—
—
—
—
10
35
45
5
5
—
5
35
—
—
—
—
—
20
—
—
15
50
65
15
10
—
5
50
—
—
—
—
—
30
—
ns
ns
ns
ns
ns
ns
ns
ns
4
4
4
4
15
4
4
4
18
0
45
35
10
—
—
—
—
—
20
0
50
40
10
—
—
—
—
—
ns
ns
ns
ns
ns
3
3
3
3
3
45
35
35
10
—
—
—
—
50
40
40
10
—
—
—
—
ns
ns
ns
ns
2,18
2,18
2,18
2,17,18
—
—
45
45
—
—
65
65
ns
ns
2
2
20
20
20
—
—
—
20
20
20
—
—
—
ns
ns
ns
18
18
17
45
35
35
10
—
—
—
—
—
35
50
40
40
10
—
—
—
—
—
50
ns
ns
ns
ns
ns
5
5
5
5
5
—
—
—
—
35
—
—
—
—
35
30
30
45
45
—
30
30
45
45
—
—
—
—
—
40
—
—
—
—
40
45
45
65
65
—
45
45
65
65
—
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
6
7
8,9,10
11
15
6
7
8,9,10
11
16
NOTE:
1. Values guaranteed by design, not tested.
2753 tbl 08
5.37
6
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
AC ELECTRICAL CHARACTERISTICS
(Commercial: VCC = 5.0V ± 10%, TA = 0°C to +70°C)
Symbol
Parameter
DEPTH EXPANSION MODE TIMINGS
tXOL
Read/Write to XO LOW
tXOH
Read/Write to XO HIGH
tXI
XI Pulse Width
tXIR
XI Recovery Time
tXIS
XI Set-up Time
SERIAL-INPUT MODE TIMINGS
tS2
Serial Data In Set-up Time to SICP Rising Edge
tH2
Serial Data In Hold Time to SICP Rising Edge
tS3
SIX Set-up Time to SICP Rising Edge
tS4
W Set-up Time to SICP Rising Edge
tH4
W Hold Time to SICP Rising Edge
tSICW
Serial In Clock Width High/Low
tS5
SI/PI Set-up Time to SICP Rising Edge
SERIAL-OUTPUT MODE TIMINGS
tS6
SO/PO Set-up Time to SOCP Rising Edge
tS7
SOX Set-up Time to SOCP Rising Edge
tS8
R Set-up Time to SOCP Rising Edge
tH8
R Hold Time to SOCP Rising Edge
tSOCW
Serial Out Clock Width HIGH/LOW
SERIAL MODE RECOVERY TIMINGS
tREFSO
Recovery Time SOCP after EF Goes HIGH
tRFFSI
Recovery Time SICP after FF Goes HIGH
SERIAL MODE FLAG TIMINGS
tSOCEF
SOCP Rising Edge (Bit 0- Last Word) to EF LOW
tSOCFF
SOCP Rising Edge (Bit 0- First Word) to FF HIGH
tSOCF
SOCP Rising Edge to FF-1, HF, AEF HIGH
tSOCF
SOCP Rising Edge to AEF, EF, EF+1 LOW
tSICEF
SICP Rising Edge (Last Bit-First Word) to EF HIGH
tSICFF
SICP Rising Edge (Bit 1-Last Word) to FF LOW
tSICF
SICP Rising Edge to EF+1, AEF HIGH
tSICF
SICP Rising Edge to FF-1, HF, AEF HIGH
SERIAL-INPUT MODE TIMINGS
tPD1
SICP Rising Edge to D(1)
SERIAL-OUTPUT MODE TIMINGS
tPD2
SOCP Rising Edge to Q(1)
tSOHZ
SOCP Rising Edge to SO at High-Z(1)
tSOLZ
SOCP Rising Edge to SO at Low-Z(1)
tSOPD
SOCP Rising Edge to Valid Data on SO
OUTPUT ENABLE/DISABLE TIMINGS
tOEHZ
Output Enable to High-Z (Disable)(1)
tOELZ
Output Enable to Low-Z (Enable)(1)
tAOE
Output Enable to Data Valid (Q0-8)
Commercial
IDT72103L35
IDT72103L50
IDT72104L35
IDT72104L50
Min.
Max.
Min.
Max.
Unit
Timing
Figure
—
—
35
10
15
35
35
—
—
—
—
—
50
10
15
50
50
—
—
—
ns
ns
ns
ns
ns
13
13
14
14
14
12
0
5
5
7
8
35
—
—
—
—
—
—
—
15
0
5
5
7
10
50
—
—
—
—
—
—
—
ns
ns
ns
ns
ns
ns
ns
19
19
19
19
19
19
19
35
5
5
7
8
—
—
—
—
—
50
5
5
7
10
—
—
—
—
—
ns
ns
ns
ns
ns
20
20
20
20
20
35
15
—
—
80
15
—
—
ns
ns
22
23
—
—
—
—
—
—
—
—
20
30
30
30
45
30
45
45
—
—
—
—
—
—
—
—
25
40
40
40
65
40
65
65
ns
ns
ns
ns
ns
ns
ns
ns
22
24
24,26
22,26
21
23
21,25
23,25
5
17
5
20
ns
17,19
5
5
5
—
17
16
22
18
5
5
5
—
20
16
22
18
ns
ns
ns
ns
20
20
20
20
—
5
—
16
—
20
—
5
—
16
—
22
ns
ns
ns
12
12
12
NOTE:
1. Values guaranteed by design, not tested.
2753 tbl 09
5.37
7
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
GENERAL SIGNAL DESCRIPTION
INPUTS:
Data Inputs (D0-D8)
The parallel-in mode is selected by connecting the SI/PI pin
to VCC. D0-D8 are the data input lines.
The serial-input mode is selected by grounding the SI/PI
pin. The D0-D8 lines are control output pins used to program
the serial word width.
Reset (RS)
Reset is accomplished whenever the RS input is taken to
a low state. Both internal read and write pointers are set to the
first location during reset. A reset is required after power up
before a write operation can take place. Both Read (R) and
Write (W) inputs must be HIGH during reset.
Write (W)
A write cycle is initiated on the falling edge of W provided
the Full Flag (FF) is not asserted. Data set-up and hold times
must be met with respect to the rising edge of W. Data is
stored in the RAM array sequentially and independently of
any on going read operation.
When the FIFO is full, the FF will go LOW inhibiting further
write operations to prevent data overflow. After a valid read
operation is completed, the FF will go HIGH after tRFF allowing
a valid write to begin.
Read (R)
A read cycle is initiated on the falling edge of R, provided
the EF is not set. Data is accessed on a first-in/first out basis
independent of any on going write operations. After R goes
HIGH, the Data Outputs (Q0-Q8) go to a high-impedance
condition until the next read operation. When all the data has
been read from the FIFO, the EF will go LOW, and Q0-Q8 will
go to a high-impedance state inhibiting further read operations. After the completion of a valid write operation, the EF will
go HIGH after tWEF allowing a valid read to begin.
First Load/Retransmit (FL/RT)
In the depth-expansion mode, the FL/RT pin is grounded to
indicate that it is the first device loaded. In the single-device
mode, the FL/RT pin acts as the retransmit input. The singledevice mode is initiated by grounding the Expansion-ln (XI)
pin.
The IDT72103/72104 can be made to retransmit data
when the RT input is pulsed LOW. A retransmit operation will
set the internal read pointer to the first location and will not
affect the write pointer. During retransmit, R and W must be
set HIGH and the FF will be affected depending on the relative
locations of the read and write pointers. This feature is useful
when less than 2048/4096 writes are performed between
resets. The retransmit feature is not available in the depth
expansion mode.
Expansion In (XI)
The XI pin is grounded to indicate an operation in the the
single-device mode. In the depth expansion or daisy-chain
mode, the XI pin is connected to the XO pin of the previous
device.
Output Enable (OE)
When OE is HIGH, the parallel output buffers are tristated.
When OE is LOW, both parallel and serial outputs are enabled.
Serial Input (SI)
Serial data is read into the serial input register via the Sl pin.
In both depth and serial width expansion modes, the serialinput signals of the different FlFOs in the expansion array are
connected together.
Serial Input Clock (SICP)
Serial data is read into the serial input register on the rising
edge of the SICP signal. In both depth and serial width
expansion modes, the SICP signals of the different FlFOs in
the expansion array are connected together.
Serial Output Clock (SOCP)
New serial data bits are read from the serial output register
on the rising edge of the SOCP signal. In both depth and serial
width expansion modes, the SOCP signals of the different
FlFOs in the expansion array are connected together.
Serial Input Expansion (SIX)
The SlX pin is tied HIGH for single-device serial or parallel
input operation. In a serial input configuration, the SIX pin of
the least significant device is tied HIGH. The SIX pin of all other
devices is connected to the D8 pin of the previous device.
Serial Output Expansion (SOX)
The SOX pin is tied HIGH for single-device serial or parallel
output operation. In a serial output configuration, the SOX pin
of the least significant device is tied HIGH. The SOX pin of all
other devices is connected to the Q8 pin of the previous device.
Serial/Parallel Input (SI/PI)
The SI/PI pin programs whether the IDT72103/72104
accepts parallel or serial data as input. When this pin is LOW,
the FIFO expects serial data and the D0-D8 pins become
output pins used to program the write signal and the serial
input word width. For instance, connecting D8 to W will
program a serial word width of 9 bits; connecting D7 to W will
program a serial word width of 8 bits and so on.
Serial/Parallel Output (SO/PO)
The SO/PO pin programs whether the IDT72103/72104
outputs parallel or serial data. When this pin is LOW, the FIFO
expects serial data and the Q0-Q8 pins output signals used to
program the read signal and the serial output word width.
5.37
8
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
OUTPUTS:
Data Outputs (Q0–Q8)
Data outputs for 9-bit wide data. These output lines are in
a high-impedance condition whenever R is in a high state. The
serial output mode is selected by grounding the SO/PO pin.
The Q0-Q8 lines are control pins used to program the serial
word width.
Serial Output (SO)
Serial data is output on the SO pin. In both depth and serial
width expansion modes the serial output signals of the
different FlFOs in the expansion array are connected
together. Following reset, SO is tristated until the first rising
edge of the Serial Out Clock (SOCP) signal. Data is clocked
out least significant bit first. In the serial width expansion
mode, SO is tristated again after the ninth bit is output.
Full Flag (FF)
FF is asserted LOW when the FIFO is full. When the FIFO
is full, the internal write pointer will not be incremented by any
additional write pulses.
Full Flag — Serial In Mode
When the FIFO is loaded serially, the Serial In Clock (SICP)
asserts the FF. On the second rising edge of the SICP for the
last word in the FIFO, the FF will assert LOW, and it will remain
asserted until the next read operation. Note that when the FF
is asserted, the last SICP for that word will have to be stretched
as shown in Figure 23.
Full Flag — Parallel–ln Mode
When the FIFO is in the Parallel-ln mode, the falling edge
of W asserts the FF (LOW). The FF is then de-asserted (HIGH)
by subsequent read operations - either serial or parallel.
Full–Minus — One Flag (FF–1)
The FF–1 flag is asserted low when the FIFO is one word
away from being full. It will remain asserted when the FIFO is
full.
Expansion Out/Half–Full Flag (XO/HF)
In the single-device mode, the XO/HF pin operates as a HF
pin when the Xl pin is grounded. After half of the memory is
filled, the HF will be set to LOW at the falling edge of the next
write operation. It will remain set until the difference between
the write pointer and read pointer is less than or equal to onehalf of the FIFO total memory. The HF is then reset by the
rising edge of the read operation.
In the multiple-device mode, the XI pin is connected to the
XO pin of the previous device. The XO pin signals a pulse to
the next device when the previous device reaches the best
location of memory in the daisy chain configuration.
Almost–Empty or Almost–Full Flag (AEF)
The AEF asserts LOW if there are 0-255 or 1793-2048
bytes in the IDT72103, 2K x 9 FIFO. The AEF asserts LOW
if there are 0-511 or 3585-4096 bytes in the IDT72104, 4K x
9 FIFO.
Empty–Plus–One Flag (EF+1)
In the parallel-output mode, the EF+1 flag is asserted LOW
when there is one word or less in the FIFO. It will remain LOW
when the FIFO is empty.
In the serial-output mode, the EF+1 flag operates as an
EF+2 flag. It goes LOW when the second to the last word is
read from the RAM array and is ready to be shifted out.
Empty Flag (EF) — Parallel–Out Mode
When the FIFO is in the parallel out mode and there is only
one word in the FIFO, the falling edge of the R line will cause
the EF line to be asserted LOW. This is shown in Figure 6. The
EF is then de-asserted HIGH by either the rising edge of W or
the rising edge of SICP, as shown in Figure 6.
Empty Flag — Serial–Out Mode
The use of the EF is important for proper serial-out operation when the FIFO is almost empty. The EF flag is asserted
LOW after the first bit of the last word is shifted out. This is
shown in Figure 22.
TABLE 1 — STATUS FLAGS
Number of
Words in FIFO
IDT72103
IDT72104
'
(1)
FF FF-1 AEF HF EF+1 EF
0
0
H
H
L
H
L
L
1
1
H
H
L
H
L
H
2-255
2-511
H
H
L
H
H
H
256-1024
512-2048
H
H
H
H
H
H
1025-1792
2049-3584
H
H
H
L
H
H
1793-2046
3585-4094
H
H
L
L
H
H
2047
4095
H
L
L
L
H
H
2048
4096
L
L
L
L
H
NOTE:
1. EF+1 acts as EF+2 in the serial out mode.
5.37
H
2753 tbl 10
9
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
PARALLEL TIMINGS:
t RSC
t RS
RS
t RSS
t RSR
W
t RSS
R
t RSF1
AEF, EF+1, EF
t RSF2
FF-1, HF, FF
2753 drw 05
Figure 2. Reset
t RC
t WC
R
W
t RPW
t WPW
t WR
Q 0–8
VALID DATA
0–8
t RLZ
t DS
t DH
t RR
t DV
tA
2753 drw 06
t RHZ
2753 drw 07
Figure 3. Write Operation in Parallel Data In Mode
Figure 4. Read Operation in Parallel Data Out Mode
t RTC
t RT
RT
t RTS
t RTR
W, R
t RTF
FLAG
VALID
All Flags
2753 drw 08
Figure 5. Retransmit
5.37
10
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
(1)
R
EF
t REF (2)
(3)
W
t WEF
2753 drw 09
NOTES:
1. Data is valid on this edge.
2. The Empty Flag is asserted by R in the Parallel-Out mode and is specified by tREF. The EF flag is deasserted by the rising edge of W.
3. First rising edge of Write after EF is set.
Figure 6. Empty Flag Timings in Parallel Out Mode
W
FF
t RFF (1)
R
t WFF
2753 drw 10
NOTE:
1. For the assertion time, tWFF is used when data is written in the Parallel mode. The FF is de-asserted by the rising edge of R.
Figure 7. Full Flag Timings in Parallel-In Mode
t WF
t WF
W
W
t RF
t RF
R
AEF
R
Almost
Empty
Almost
Empty
AEF
Almost
Full
2753 drw 11
2753 drw 12
Figure 8. Almost-Empty Flag Region
Figure 9. Almost-Full Flag Region
5.37
11
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
W
t WF
HF, FF-1
t RF
R
2753 drw 13
Figure 10. Half-Full and Full-minus-1 Flag Timings
R
t RE
EF+1
t WE
W
2753 drw 14
Figure 11. Empty+1 Flag Timings
t RC
t RR
R
TERMINATE READ CYCLE
tA
OE
tRLZ
Q0-8
SECOND READ BY CONTROLLING OE
tAOE
tOELZ
tOEHZ
DATA 1
tDV
DATA 1
2753 drw 15
Figure 12. Output Enable Timings
W
WRITE TO
LAST PHYSICAL
LOCATION
READ FROM
LAST PHYSICAL
LOCATION
R
t XOL
t XOH
t XOL
t XOH
XO
2753 drw 16
Figure 13. Expansion-Out
5.37
12
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
t XI
t XIR
XI
t XIS
W
WRITE TO
FIRST PHYSICAL
LOCATION
t XIS
READ FROM
FIRST PHYSICAL
LOCATION
R
2573 drw 17
Figure 14. Expansion-In
Dn
W
t RPE
R
EF
t WEF
t REF
tA
t WLZ
Qn
DATA OUT VALID
2753 drw 18
Figure 15. Read Data Flow-Through Mode
R
t WPF
W
t RFF
t WFF
FF
t DH
t DS
DATA IN VALID
Dn
tA
Qn
DATA OUT VALID
2753 drw 19
Figure 16. Write Data Flow-Through Mode
5.37
13
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
SERIAL TIMINGS:
t RS
RS
t RSS
SICP
(1)
SICP
(1)
t RSR
0
0
i
i-1
i
t PD1
D0
t PD1
D 1-8
t RSDL
2753 drw 20
NOTE:
1. SICP should be in the steady LOW or HIGH during tRSS. The first LOW-HIGH (or HIGH-LOW) transition can begin after tRSR.
Figure 17. Reset Timings for Serial-In Mode
t RSC
t RS
RS
t RSS
SOCP
(1)
SOCP
(1)
t RSR
Q 0-8
t RSQH
t RSQL
2753 drw 21
NOTE:
1. SOCP should be in the steady LOW or HIGH during tRSS. The first LOW-HIGH (or HIGH-LOW) transition can begin after tRSR.
igure 18. Reset Timings for Serial-Out Mode
5.37
14
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
t SICW
0
t SICW
(1)
n–1
2
1
SICP
1/t SICP
SI/PI
(3)
t S5
SIX
t S3
SI
t S2
t H2
Di
t S4 (2)
t PD1
t H4 (2)
W
2753 drw 22
NOTES:
1. For the stand alone mode, n ≥ 4 and the input bits are numbered 0 to n-1.
2. For the recommended interconnections, Di is to be directly tied to W and the tS4 and tH4 requirements will be satisfied. For users that modify W
externally, tS4 and tH4 requirements have to be met.
3. After SI/PI has been set up, it cannot be dynamically changed; it can only be changed after a reset operation.
Figure 19. Write Operation In Serial-ln Mode
t SOCW
t SOCW
1
0
n–1
SOCP
1/t SOCP
SO/PO
(1)
t S6
SOX
t S7
Qi
t PD2
t S8
t H8
R
(2)
SO
t SOHZ
SO
(3)
t SOLZ
t SOPD
2753 drw 23
NOTES:
1. After SO/PO has been set up, it cannot be dynamically changed; it can only be changed after a reset operation.
2. For single device: Read out the last bit after EF is asserted.
For Serial Width Expansion mode: Read out the last bit of the current memory location from the active device.
3. For single device: The operation starts after Reset.
For Serial Width Expansion mode: Read the first bit of the current memory location from the active device.
Figure 20. Read Operation In Serial-Out Mode
5.37
15
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
FIRST
SERIAL-IN WORD
0
1
n–1
SECOND
SERIAL-IN WORD
0
1
n–1
THIRD
SERIAL-IN
WORD
0
SICP
D n-1 =W
t PD1
t SICEF
(2)
EF
tREF
(3)
t SICF
EF+1
t RE
R
(1)
2753 drw 24
NOTES:
1. Parallel Read shown for reference only. Can also use serial output mode.
2. The Empty Flag is de-asserted after the N–1 rising edge of SICP of the first serial-in word. In the Serial-Out mode, a new read operation can begin
tREFSO after EF goes HIGH. In the Parallel-Out mode, a new read operation can occur immedately after FF goes HIGH.
3. The EF+1 Flag is de-asserted after the N–1 rising edge of SICP of the second serial-in word.
Figure 21. Empty Flag and Empty+1 Flag De-assertion in the Serial-ln Mode
0
1
SERIAL
WORD A
n-2
n-1
0
1
SERIAL
WORD B
n-2
n-1
LAST SERIAL
WORD
1
n-2
0
n-1
0
1
SOCP
tSOCF
R=Q n-1
EF+1
t SOCEF
t REFSO
(2)
EF
t WEF
(1)
(3)
W
WORD
A
WORD THIRD
B
WORD
2753 drw 25
NOTES:
1. Parallel write shown for reference only. Can also use serial input mode.
2. The Empty Flag (EF) is asserted in Serial-Out mode by using the tSOCEF parameter. This parameter is measured in the worst case condition from the
rising edge of the SOCP used to clock data bit 0. Whenever EF goes LOW, there is only one word to be shifted out. In the Parallel-ln mode, the EF
flag is de-asserted by the rising edge of W. In the Serial-ln mode, the EF flag is de-asserted by the rising edge of W.
3. First Write rising edge after EF is set.
4. Once EF has gone LOW and the last bit of the final word has been shifted out, SOCP should not be clocked until EF goes HIGH.
Figure 22. Empty Flag and Empty+1 Flag Assertion in the Serial-Out Mode (FIFO Being Emptied)
5.37
16
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
0
NEXT TO LAST
SERIAL WORD
1
n-2
COMMERCIAL TEMPERATURE RANGES
n-1
LAST SERIAL
WORD
1
n-2
0
n-1
0
1
SICP
W=D n-1
t SICF
FF-1
t SICFF
t RFFSI
(1)
FF
t RFF
(2)
R
2753 drw 26
NOTES:
1. The Full Flag is asserted in the Serial-ln mode by using the tSICFF parameter. This parameter is measured in the worst case condition from the rising
edge of SICP following a (tPD1+tWFF) delay from the first SICP rising edge of the last word.
2. First Read rising edge after FF is set.
3. After FF goes LOW and the last bit of the final word has been clocked in, SICP should not be clocked until FF goes HIGH.
Figure 23. Full Flag and Full-1 Flag Assertlon in the Serial-ln Mode (FIFO Being Filled)
FIRST
SERIAL-OUT WORD
0
1
n–1
SECOND
SERIAL-OUT WORD
0
1
n–1
SOCP
Q n+1 =R
(1)
t PD2
(2)
FF
tWFF
t SOCFF
t SOCF
FF-1
t WF
W
2753 drw 27
NOTES:
1. The FIFO is full and a new read sequence is started.
2. On the first rising edge of SOCP, the FF is de-asserted. In the Serial-ln mode, a new write operation can begin following tRFFS1 after FF, goes HIGH.
In the Parallel-ln mode, a new write operation can occur immediately after FF goes HIGH.
3. The FF-1 flag is de-asserted after the first SOCP of the second serial word.
Figure 24. Full Flag and Full-1 Flag De-assertion in the Serial-Out Mode
5.37
17
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
R
HF
HALF-FULL (1/2)
HALF-FULL + 1
t RF
HALF-FULL + 1
t SICF
0
1
n–1
0
SICP
t SICF
AEF
ALMOST-FULL
(7/8 Full)
ALMOST-FULL + 1
(7/8 Full + 1)
ALMOST-EMPTY – 1
(1/8 Full–1)
ALMOST-EMPTY
(1/8 Full)
ALMOST-FULL + 1
(7/8 Full + 1)
t RF
AEF
ALMOST-EMPTY
(1/8 Full)
2753 drw 28
Figure 25. Half-Full, Almost-Full and Almost-Empty Timings for Serial-In Mode
W
HF
HALF-FULL +1
HALF-FULL (1/2)
tWF
t SOCF
HALF-FULL (1/2)
0
1
n–1
0
SOCP
t SOCF
AEF
ALMOST-FULL
(7/8 Full)
ALMOST-FULL + 1
(7/8 Full+1)
ALMOST-FULL
(7/8 Full)
ALMOST-EMPTY
(1/8 Full)
ALMOST-EMPTY – 1
(1/8 Full–1)
tWF
AEF
ALMOST-EMPTY – 1
(1/8 Full–1)
2753 drw 29
Figure 26. Half-Full, Almost-Full and Almost-Empty Timings for Serial-Out Mode
5.37
18
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
enable and disable timings for OE are shown in Figure 12.
OPERATING DESCRIPTION
PARALLEL OPERATING MODES:
Parallel Data Input
By setting SI/PI HIGH, data is written into the FIFO in
parallel through the D0-D8 input data lines.
Parallel Data Output
By setting SO/PO HIGH, the parallel-out mode is chosen.
In the parallel-out mode, as shown in Figure 4, data is
available tA after the falling edge of R and the output bus Q
goes into high-impedance after R goes HIGH.
Alternately, the user can access the FIFO by keeping R
LOW and enabling data on the bus by asserting OE. When R
is LOW, the OE is HIGH and the output bus is tri-stated. When
R is HIGH, the output bus is disabled irrespective of OE. The
Single Device Mode
A single IDT172103/72104 may be used when application
requirements are for 2048/4096 words or less. The IDT72103/
72104 is in the Single Device Configuration when the Expansion In (Xl) control input is grounded (See Figure 27). In this
mode, the HF/XO is used as a Half-Full flag.
Wldth Expanslon Mode
Word width may be increased simply by connecting the
corresponding input control signals of multiple devices. Status flags can be detected from any one of the connected
devices. Figure 28 demonstrates an 18-bit word width by
using two IDT72103/72104s. Any word width can be attained
by adding additional IDT72103/72104.
HALF-FULL FLAG
HF
VCC
(SI/PI)
WRITE
(W)
DATAIN
9
(D)
FULL FLAG
VCC
(SO/PO)
(R)
READ
9
IDT
72103/04
(Q)
(EF)
(FF)
DATA OUT
EMPTY FLAG
(EF+1) EMPTY-PLUS-ONE
FULL-MINUS-ONE (FF-1)
ALMOST FULL
(AEF)
(AEF)
RESET
(RS)
(RT)
RETRANSMIT
(OE)
OUPUT ENABLE
EXPANSION IN (XI)
ALMOST EMPTY
2573 drw 30
Figure 27. Block Diagram of Single 2048 x 9/4096 x 9 FIFO in Parallel Mode
5.37
19
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
INPUT CONFIGURATION TABLE
Serial Input
Width Expansion
Parallel
Input
HIGH
Single
Device
LOW
Least Significant
Device
LOW
All Other
Devices
LOW
Most Significant
Device
LOW
Sl
HIGH or LOW
Input Data
Input Data
Input Data
Input Data
SICP
HIGH or LOW
Input Clock
Input Clock
Input Clock
Input Clock
HIGH
HIGH
HIGH
D 8 of next least
significant device
D 8 of next least
significant device
Write Control
Di
Di of most
significant device
Di of most
significant device
Di of most
significant device
Input Data
No connect
except Di
No connect except D8
No connect except D8
No connect except Di
—
W
—
—
W of all devices
—
—
SIX of next most
significant device
SIX of next most
significant device
Pin
SI /PI
SIX
W
D0 -D 8
Di(1)
D8
—
NOTE:
2753 tbl 11
1. Di refers to the rnost significant bit of the serial word. If multiple devices are width cascaded, Di is the rnost significant bit from the most
significant device.
OUTPUT CONFIGURATION TABLE
Serial Output
Width Expansion
Pin
SO/PO
SO
Parallel
Output
Single
Device
Least Significant
Device
All Other
Devices
Most Significant
Device
HIGH
LOW
LOW
LOW
LOW
—
Output Data
Output Data
Output Data
Output Data
HIGH or LOW
Output Clock
Output Clock
Output Clock
Output Clock
HIGH
HIGH
HIGH
Q 8 of next least
significant device
Q 8 of next least
significant device
R
Read Control
Qi
Qi of most
significant device
Qi of most
significant device
Qi of most
significant device
Q0 -Q8
Output Data
No connect
except Di
No connect except Q 8
No connect except Q 8
No connect except Qi
—
—
R of all devices
SOX of next most
significant device
SOX of next most
significant device
SOCP
SOX
Qi(1)
Q8
—
R
—
—
—
NOTE:
2753 tb l 12
1. Qi refers to the most significant bit of the serial word. If multiple devices are width cascaded, Qi is the rnost significant bit from the most
significant device.
5.37
20
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
18
DATAIN
COMMERCIAL TEMPERATURE RANGES
HF
HF
9
9
(SO/PO)
(D)
(SO/PO)
WRITE
(W)
FULL FLAG (FF)
RESET
(RS)
(R)
IDT
72103/04
IDT
72103/04
9
VCC
(SI/PI)
VCC
OUTPUT
(OE) ENABLE
READ
(EF) EMPTY FLAG
(RT) RETRANSMIT
9
(SI/PI)
(XI)
(XI)
(Q) DATAOUT
18
2753 drw 31
NOTE:
1. Flag detection is accomplished by monitoring all the flag signals of either (any) device used in the width expansion configuration. Do not connect any
flag signals together.
Figure 28. Block Diagram of 2048 x 18/4096 x 18 FIFO Memory Used in Width Expansion in Parallel Mode
TRUTH TABLES
TABLE 2: RESET AND RETRANSMIT —
SINGLE DEVICE CONFIGURATION/WIDTH EXPANSION IN PARALLEL MODE
Inputs(2)
Internal Status(1)
RS
FL
XI
Read Pointer
Reset
0
X
0
Retransmit
1
0
0
Mode
Read/Write
1
1
0
NOTES:
1. Pointer will increment if appropriate flag is HIGH.
2. RS = Reset Input, FL/RT = First Load/Retransmit,
Outputs
Write Pointer
AEF , EF
FF
HF
Location Zero
Location Zero
0
1
1
Location Zero
Unchanged
X
X
X
(1)
X
X
(1)
Increment
Increment
X
2753 tbl 13
EF = Empty Flag Output, FF = Full Flag Output,
5.37
XI = Expansion Input.
21
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
DEPTH EXPANSION (DAISY CHAIN) MODE
The IDT72103/4 can be easily adapted to applications
where the requirements are for greater than 2048/4096 words.
Figure 29 demonstrates Depth Expansion using three
IDT72103/4s. Any memory depth can be attained by adding
additional IDT72103/4s. The IDT72103/4 operates in the
Depth Expansion configuration when the following conditions
are met:
1. The first device must be designated by grounding the
First Load (FL) control input pin.
2. All other devices must have the FL pin in the high state.
3. The Expansion Out (XO) pin of each device must be tied
to the Expansion In (Xl) pin of the next device. See
Figure 29.
4. External logic is needed to generate a composite
Full Flag (FF) and Empty Flag (EF). This requires the
OR-ing of all EFs and OR-ing of all FFs (i.e., all must be
set to generate the correct composite FF or EF). See
Figure 29.
5. The Retransmit (RT) function and Half-Full Flag (HF) are
not available in the Depth Expansion mode.
XO
W
R
9
FF
9
D
EF
9
IDT
72103/04
Q
FL
Vcc
XI
XO
FF
9
FULL
EF
IDT
72103/04
EMPTY
FL
XI
XO
FF
9
EF
IDT
72103/04
FL
RS
XI
2753 drw 32
NOTE:
1. SI/PI and SO/PO pins are tied to VCC.
Figure 29. Block Diagram of 6,144 x 9/12,288 x 9-FIFO Memory, Depth Expansion in Parallel Mode
5.37
22
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
BIDIRECTIONAL MODE
Applications requiring data buffering between two systems
(each system capable of Read and Write operations) can be
achieved by pairing IDT72103/4 as shown in Figure 30. Both
Depth Expansion and Width Expansion may be used in this
mode.
WA
FF A
IDT
72103/04
D A 0–8
RB
EF B
HF B
OE
Q B 0–8
SYSTEM A
SYSTEM B
Q A 0–8
OE
RA
HF A
EF A
D B 0–8
IDT
72103/04
WB
FF B
2573 drw 33
NOTE:
1. SI/PI and SO/PO pins are tied to VCC.
Figure 30. Bidirectional FIFO Mode
COMPOUND EXPANSION MODE
The two expansion techniques described above can be
applied together in a straightforward manner to achieve large
FIFO arrays (see Figure 31).
Q 0–Q 8
Q 0 –Q 8
R, W, RS
IDT72103/72104
DEPTH
EXPANSION
BLOCK
Q N–8 –Q N
Q 9 –Q 17
Q N–8 –Q N
IDT72103/72104
DEPTH
EXPANSION
BLOCK
D 0 –D 8
D 0 –D N
Q 9–Q 17
IDT72103/72104
DEPTH
EXPANSION
BLOCK
D 9 –D 17
D 9 –D N
D 18 –D N
D N–8 –D N
D N–8 –D N
2753 drw 34
NOTE:
1. SI/PI and SO/PO pins are tied to VCC.
2. For depth expansion block see DEPTH EXPANSION Section and Figure 29.
3. For Flag Detection see WIDTH EXPANSION SECTION and Figure 28.
Figure 31. Compound FIFO Expansion
5.37
23
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
TABLE 3: RESET AND FIRST LOAD TRUTH TABLE —
DEPTH EXPANSION/COMPOUND EXPANSION MODE
Inputs
(2)
Internal Status
RS
FL
XI
Read Pointer
Reset-First
Device
0
0
(1)
Retransmit all
Other Devices
0
1
Read/Write
1
X
Mode
NOTES:
1. XI is connected to
2. RS = Reset Input,
Outputs
Write Pointer
EF
FF
Location Zero
Location Zero
0
1
(1)
Location Zero
Location Zero
0
1
(1)
X
X
X
X
XO of previous device.
FL/RT = First Load/Retransmit, EF = Empty Flag Ouput,
SERIAL OPERATING MODES:
Serial Data Input
The Serial Input mode is selected by grounding the Sl/PI
line. The D0-8 lines are then outputs which are used to
program the width of the serial word. They are taps off a digital
delay line which are meant for connection to the W input. For
instance, connecting D6 to W will program a serial word width
of 7 bits, connecting D7 to W will program a serial word width
of 8 bits and so on.
By programming the serial word width, an economy of
clock cycles is achieved. As an example, if the word width is
6 bits, then on every 6th clock cycle the serial data register is
written in parallel into the FIFO RAM array. Thus, the possible
clock cycles for an extra 3 bits of width in the RAM array are
not required.
The SIX signal is used for Serial-ln Expansion. When the
serial word width is 9 or less, the SIX input must be tied HIGH.
When more than 9 bits of serial word width is required, more
than one device is required. The SIX input of the least
significant device must be tied HIGH. The D8 pin of the least
significant device must be tied to SIX of the next significant
device. In other words, the SIX input of the most significant
and intermediate devices must always be connected to the D8
of the next least significant device.
Figure 32 shows the relationship of the SIX, SICP and D08 lines. In the stand alone case (Figure 32), on the first LOWto-HlGH of SICP, the D1-8 lines go LOW and the D0 line
remains HIGH. On the next SICP clock edge, the D1 goes
HIGH, then D2 and so on. This continues until the D line, which
is connected to W, goes HIGH. On the next clock cycle, after
W is HIGH, all of the D lines go LOW again and a new serial
word input starts.
2753 tbl 14
FF = Full Flag Output,
XI = Expansion Input.
In the cascaded case, the first LOW-to-HlGH SICP clock
edge for a serial word will cause all timed outputs (D) to go
LOW except for D0 of the least significant device. The D
outputs of the least significant device will go high on consecutive clock cycles until D8. When D8 goes HlGH, the SlX of the
next device goes HlGH. On the next cycle after the SIX input
is brought HIGH, the D0 goes HIGH; then on the next cycle D1
and so on. A Di output from the most significant device is
issued to create the W for all cascaded devices.
The minimum serial word width is 4 bits and the maximum
is virtually unlimited.
When in the Serial mode, the Least Significant Bit of a serial
stream is shifted in first. If the FIFO output is in the Parallel
mode, the first serial bit will come out on Q0. The second bit
shifted in is on Q1 and so on.
In the Serial Cascade mode, the serial input (Sl) pins must
be connected together. Each of the devices then receives
serial information together and uses the SIX and D0-8 lines to
determine whether to store it or not.
The example shown in Figure 34 shows the interconnections for a serializing FIFO that transfers data to the internal
RAM in 16-bit quantities (i.e. every 16 SlCP cycles). This
corresponds to incrementing the write pointer every 16 SICP
cycles.
Once W goes HIGH With the last serial bit in, SICP should
not be clocked again until FF goes HIGH.
5.37
24
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
SINGLE DEVICE SERIAL INPUT CONFIGURATION
SICP
SERIAL-IN CLOCK
V CC
1
2
3
V CC
SI/PI
SO/PO
SI
SERIAL-IN DATA
0
GND
IDT72103/4
Q 0-7
8
SIX
W D0 D1 D2 D3 D4 D5 D6 D7 D8
4
5
6
7
0
1
2
3
4
5
6
7
0
SICP
D 0 =1
D1
D2
D3
D4
D5
D6
D7
W
2753 drw 35
Figure 32. Serial-In Mode Where 8-Bit Parallel Output Data is Read
SERIAL DATA IN
SERIAL-INPUT
CLOCK
DATA IN/TIMED
OUTPUTS D0-8
RGTR
9
9
MUX
W
DELAYED
TIMING
GENERATOR
SI/PI
DATA IN TO
FIFO RAM
Figure 33. Serial-Input Circuitry
5.37
25
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
SERIAL INPUT WIDTH EXPANSION
SERIAL-IN
DATA
SERIAL-IN
CLOCK
V CC
GND
V CC
SI/PI
SO/PO
SI
GND
V CC
SI/PI
SO/PO
SI
SICP
SIX
Q 0-8
IDT72103/104
FIFO #1
SICP
IDT72103/104
FIFO #2
SIX
D8
W
W
D 6 Q 0-6
7
9
9
16-BIT
PARALLEL
OUTPUT
0
1
7
8
9
10
14
15
0
SICP
D 8 OF FIFO #1
AND SIX OF
FIFO #2
D 6 OF FIFO #2
AND W OF
FIFO #1 AND
FIFO #2
2753 drw 37
Figure 34. Serial-In Configuration for Serial-In to Parallel-Out Data of 16 bits
SERIAL INPUT WITH DEPTH EXPANSION
Q 0-7
VCC
GND
VCC
SI/PI SO/PO
SIX
IDT72104
FL/RT
SOX
SI
SICP
XO XI
Q 0-7
R
D7
R
W
VCC
SICP
GND
VCC
VCC
XI XO
SI/PI SO/PO
SIX
IDT72104
FL/RT
SOX
SI
SICP
Q 0-7
R
D7
W
VCC
2753 drw 38
SI
NOTE:
1. All SI/PI pins are tied to GND and SO/PO pins are tied to VCC.
OE
is tied LOW. For FF and EF connections see Figure 29.
Figure 35. An 8K x 8 Serial-In, Parallel-Out FIFO
5.37
26
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
SERIAL INPUT WITH WIDTH AND DEPTH EXPANSION
SERIAL
DATA IN
VCC
SI
SIX
SICP
D8
IDT72104
SI
SIX
SIX
SI
SICP
IDT72104
W
SICP
IDT72104
R
Q 0-8
D8
W
Q 0-8
XI XO
D5
R
W
R
Q 0-5
XI XO
XI XO
VCC
SERIAL
INPUT
CLOCK
SIX SI D 8 XO XI
SIX SI D 8 XO XI
W
SICP
IDT72104
SIX SI D 5 XO XI
W
SICP
R
IDT72104
W
SICP
R
IDT72104
Q 0-8
Q 0-8
Q 0-5
P 0-8
P 9-17
P 18-23
R
READ
2753 drw 39
PARALLEL DATA OUT
NOTE:
1. All SI/PI pins are tied to GND.
SO/PO pins are tied to VCC.
For FL/RT, FF and EF connections see Figure 29.
Figure 36. An 8K x 24 Serial-In, Parallel-Out FIFO Using Six IDT72104s
SERIAL DATA OUTPUT
The Serial Output mode is selected by setting the SO/PO
line LOW. When in the Serial-Out mode, one of the Q1-8 lines
should be used to control the R signal. In the Serial-Out mode,
the Q0-8 are taps off a digital delay line. By selecting one of
these taps and connecting it to R, the width of the serial word
to be read and shifted is programmed. For instance, if the Q5
line is connected to the R input, on every sixth clock cycle a
new word is read from the FIFO RAM array and begins to be
shifted out. The serial word is shifted out Least Significant Bit
first. If the input mode of the FIFO is parallel, the information
that was written into the D0 bit will come out as the first bit of
the serial word. The second bit of the serial stream will be the
D1 bit and so on.
In the stand alone case, the SOX line is tied HIGH and not
used. On the first LOW-to-HIGH of the SOCP clock, all of the
Q outputs except for Q0 go LOW and a new serial word is
started. On the next clock cycle, Q1 will go HIGH, Q2 on the
next clock cycle and so on, as shown in Figure 37. This
continues until the Q line, which is connected to R, goes HIGH
at which point all of the Q lines go LOW on the next clock and
a new word is started.
In the cascaded case, word width of more than 9 bits can
be achieved by using more than one device. By tying the SOX
line of the least significant device HIGH and the SOX of the
subsequent devices to Q8 of the previous device, a cascaded
serial word is achieved. On the first LOW-to-HIGH clock edge
of SOCP, all the Q lines go low except for Q0. Just as in the
stand alone case, on each consecutive clock cycle, each Q
line goes HIGH in the order of least to most significant. When
Q8 (which is connected to the SOX input of the next device)
goes HIGH, the D0 of that device goes HIGH, thus cascading
from one device to the next. The Q line of the most significant
device, which programs the serial word width, is connected to
all R inputs.
The Serial Data Output (SO) of each device in the serial
word must be tied together. Since the SO pin is tri-stated, only
the device which is currently shifting out is enabled and driving
the 1-bit bus.
Figure 39 shows an example of the interconnections for a
16-bit serialized FIFO.
Once R goes HIGH with the last serial bit out, SOCP should
not be clocked again until EF goes HIGH.
5.37
27
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
V CC
SOCP SI/PI
SERIAL-OUT CLOCK
IDT72103/4
OE
SOX
R Q0 Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8
V CC
1
2
3
D 0-7
SO/PO
SO
SERIAL-OUT DATA
0
GND PARALLEL DATA IN
4
5
6
7
0
1
2
GND
3
4
5
6
7
0
SOCP
Q 0 =1
Q1
Q2
Q3
Q4
Q5
Q6
Q7
R
2753 drw 40
NOTE:
1. Input data is loaded in 8-bit quantities and read out serially.
Figure 37. Serial-Out Configuration
5.37
28
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
OUTPUT FROM
RAM ARRAY
SOCP-SERIAL
OUTPUT CLOCK
SO/PO
9
DELAYED
TIMING
GENERATOR
R
SO/PO
CONTROL
CIRCUIT
SERIALOUTPUT
DATA
(SO)
SERIAL-OUT
REGISTER
MUX
9
PARALLEL-OUT DATA/
TIMED OUTPUT Q 0-8
2753 drw 41
Figure 38. Serial-Output Circuitry
PARALLEL DATA IN
16-BITS WIDE
9
V CC
D 0-8
SO
SERIAL-OUTPUT
CLOCK
V CC
GND
SI/PI
SERIAL-OUT
DATA
SO/PO
D 0-6
SO
FIFO #1
SOCP
GND
SI/PI
SO/PO
SOX
Q8
R
1
V CC
FIFO #2
SOCP
SOX
0
7
7
R
8
9
10
14
Q6
15
0
SOCP
Q 8OF FIFO #1
AND SOX OF
FIFO #2
Q 6 OF FIFO #2
AND R OF FIFO
#1 AND FIFO #2
2753 drw 42
NOTE:
1. The parallel Data In is tied to D0-8 of FIFO #1 and D0-6 of FIFO #2.
Figure 39. Serial-Output for 16-Bit Parallel Data In
5.37
29
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9, 4096 x 9
COMMERCIAL TEMPERATURE RANGES
D 0-7
SERIAL OUTPUT WITH DEPTH EXPANSION
D 0-7
W
IDT72104
FL/RT
W
R
SOX
SO SOCP
XO XI
Q7
XI XO
D 0-7
VCC
SOCP
VCC
W
IDT72104
FL/RT
SOX
SOCP
SO
Q7
R
VCC
2753 drw 43
SO
NOTE:
1. All SI/PI pins are tied to VCC and SO/PO pins are tied to GND. OE is tied LOW. For FF and EF connections see Figure 17.
Figure 40. An 8K x 8 Parallel-In Serial-Out FIFO
SERIAL IN AND SERIAL OUT WITH WIDTH AND DEPTH EXPANSION
SICP
SI
V CC
V CC
SIX
SI SICP
D8
FL/RT
W
IDT72104
FF
R
EF
SOX SO SOCP XO XI Q 8
SIX
FL/RT
SI
SICP
D6
W
IDT72104
R
SOX SO
SOCP XO XI Q 6
FULL
FLAG
EMPTY
FLAG
V CC
V CC
V CC
SIX
SI SICP XI XO D 8
W
IDT72104
R
FL/RT
FF
EF
SOX SO
SOCP
V CC
Q8
SIX
SI
SICP XI XO D 6
FL/RT
W
IDT72104
R
SOX SO
SOCP
Q6
SOCP
SO
2753 drw 44
NOTE:
1. All RS pins are connected together. All OE pins are connected LOW. All SI/PI and SO/PO pins are grounded.
Figure 41. 128K x 1 Serial-In Serial-Out FIFO
5.37
30
IDT72103, IDT72104
CMOS PARALLEL-SERIAL FIFO 2048 x 9 AND 4096 x 9
COMMERCIAL TEMPERATURE RANGES
ORDERING INFORMATION
IDT XXXXX
Device
Type
X
Power
XXX
Speed
X
Package
X
Process/
Temperature
Range
5.37
Blank
Commercial (0°C to +70°C)
J
40-pin Plastic Leaded Chip Carrier
35
50
Commerical (50MHz serial shift rate)
Commercial (40MHz serial shift rate)
L
Low Power
72103
72104
2048 x 9-Bit Configurable Parallel-Serial FIFO
4096 x 9-Bit Configurable Parallel-Serial FIFO
2753 drw 45
31