Electronic Components Datasheet Search
  English  ▼
ALLDATASHEET.NET

X  

IDT70125L45J Datasheet(PDF) 11 Page - Integrated Device Technology

Part # IDT70125L45J
Description  HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
Download  12 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
Manufacturer  IDT [Integrated Device Technology]
Direct Link  http://www.idt.com
Logo IDT - Integrated Device Technology

IDT70125L45J Datasheet(HTML) 11 Page - Integrated Device Technology

Back Button IDT70125L45J Datasheet HTML 4Page - Integrated Device Technology IDT70125L45J Datasheet HTML 5Page - Integrated Device Technology IDT70125L45J Datasheet HTML 6Page - Integrated Device Technology IDT70125L45J Datasheet HTML 7Page - Integrated Device Technology IDT70125L45J Datasheet HTML 8Page - Integrated Device Technology IDT70125L45J Datasheet HTML 9Page - Integrated Device Technology IDT70125L45J Datasheet HTML 10Page - Integrated Device Technology IDT70125L45J Datasheet HTML 11Page - Integrated Device Technology IDT70125L45J Datasheet HTML 12Page - Integrated Device Technology  
Zoom Inzoom in Zoom Outzoom out
 11 / 12 page
background image
6.10
11
IDT 70121/70125S/L
HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
COMMERCIAL TEMPERATURE RANGE
FUNCTIONAL DESCRIPTION
The IDT70121/125 provides two ports with separate control,
address and I/O pins that permit independent access for reads
or writes to any location in memory. The IDT70121/125 has an
automatic power down feature controlled by
CE. The CE
controls on-chip power down circuitry that permits the
respective port to go into a standby mode when not selected
(
CE high). When a port is enabled, access to the entire
memory array is permitted.
INTERRUPTS
If the user chooses to use the interrupt function, a memory
location (mail box or message center) is assigned to each port.
The left port interrupt flag (
INTL) is asserted when the right port
writes to memory location 7FE (HEX), where a write is defined
as the
CE = R/W = VIL per the Truth Table. The left port clears
the interrupt by access address location 7FE access when
CER = OER= VIL,R/W is a "Don't Care". Likewise, the right port
interrupt flag (
INTR) is asserted when the left port writes to
memory location 7FF (HEX) and to clear the interrupt flag
(
INTR), the right port must access the memory location 7FF.
The message (9 bits) at 7FE or 7FF is user-defined, since it is
an addressable SRAM location. If the interrupt function is not
used, address locations 7FE and 7FF are not used as mail
boxes, but as part of the random access memory. Refer to
Table I for the interrupt operation.
BUSY LOGIC
Busy Logic provides a hardware indication that both ports of
the RAM have accessed the same location at the same time.
It also allows one of the two accesses to proceed and signals
the other side that the RAM is “Busy”. The busy pin can then
be used to stall the access until the operation on the other side
is completed. If a write operation has been attempted from the
side that receives a busy indication, the write signal is gated
internally to prevent the write from proceeding.
The use of busy logic is not required or desirable for all
applications. In some cases it may be useful to logically OR
the busy outputs together and use any busy indication as an
interrupt source to flag the event of an illegal or illogical
operation. If the write inhibit function of busy logic is not
desirable, the busy logic can be disabled by using the IDT70125
(SLAVE). In the IDT70125, the busy pin operates solely as a
write inhibit input pin. Normal operation can be programmed
by tying the
BUSY pins high. Once in slave mode the BUSY pin
operates solely as a write inhibit input pin. Normal operation
can be programmed by tying the
BUSY pins high. If desired,
unintended write operations can be prevented to a port by
tying the busy pin for that port low.
The busy outputs on the IDT70121/125 RAM in master mode,
are push-pull type outputs and do not require pull up resistors
to operate. If these RAMs are being expanded in depth, then
the busy indication for the resulting array requires the use of
an external AND gate.
WIDTH EXPANSION WITH BUSY LOGIC
MASTER/SLAVE ARRAYS
When expanding an IDT70121/125 RAM array in width while
using busy logic, one master part is used to decide which side
of the RAM array will receive a busy indication, and to output
that indication. Any number of slaves to be addressed in the
same address range as the master, use the busy signal as a
write inhibit signal. Thus on the IDT70121 RAM the busy pin
is an output of the part, and the busy pin is an input of the
IDT70125 as shown in Figure 3.
If two or more master parts were used when expanding in
width, a split decision could result with one master indicating
busy on one side of the array and another master indicating
busy on one other side of the array. This would inhibit the write
operations from one port for part of a word and inhibit the write
2654 drw 15
MASTER
Dual Port
RAM
BUSYL
BUSYR
CE
MASTER
Dual Port
RAM
BUSYL
BUSYR
CE
SLAVE
Dual Port
RAM
BUSYL
BUSYR
CE
SLAVE
Dual Port
RAM
BUSYL
BUSYR
CE
BUSYL
BUSYR
IDT70121
IDT70121
IDT70125
IDT70125
Figure 3. Busy and chip enable routing for both width and depth
expansion with IDT70121 (Master) and IDT70125 (Slave) RAMs.
operations from the other port for the other part of the word.
The busy arbitration, on a master, is based on the chip enable
and address signals only. It ignores whether an access is a
read or write. In a master/slave array, both address and chip
enable must be valid long enough for a busy flag to be output
from the master before the actual write pulse can be initiated
with either the R/
W signal or the byte enables. Failure to
observe this timing can result in a glitched internal write inhibit
signal and corrupted data in the slave.


Similar Part No. - IDT70125L45J

ManufacturerPart #DatasheetDescription
logo
Integrated Device Techn...
IDT70125L45JG IDT-IDT70125L45JG Datasheet
127Kb / 15P
   HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
IDT70125L45JGI IDT-IDT70125L45JGI Datasheet
127Kb / 15P
   HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
More results

Similar Description - IDT70125L45J

ManufacturerPart #DatasheetDescription
logo
Integrated Device Techn...
IDT70121S IDT-IDT70121S_14 Datasheet
199Kb / 16P
   HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
IDT70121S IDT-IDT70121S_06 Datasheet
127Kb / 15P
   HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
logo
Renesas Technology Corp
70121L RENESAS-70121L Datasheet
416Kb / 17P
   HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT
SEPTEMBER 2019
logo
Integrated Device Techn...
IDT70121S IDT-IDT70121S_17 Datasheet
170Kb / 16P
   HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM
IDT71V321S IDT-IDT71V321S Datasheet
129Kb / 14P
   HIGH-SPEED 3.3V 2K x 8 DUAL-PORT STATIC RAM WITH INTERRUPT
IDT7132SA IDT-IDT7132SA_15 Datasheet
203Kb / 16P
   HIGH SPEED 2K x 8 DUAL PORT STATIC RAM
IDT71321SA IDT-IDT71321SA_08 Datasheet
143Kb / 17P
   HIGH SPEED 2K X 8 DUAL-PORT STATIC RAM
IDT7132SA IDT-IDT7132SA_18 Datasheet
169Kb / 16P
   HIGH SPEED 2K x 8 DUAL PORT STATIC RAM
IDT71321SA IDT-IDT71321SA_18 Datasheet
184Kb / 18P
   HIGH SPEED 2K X 8 DUAL-PORT STATIC RAM
7132SA100J IDT-7132SA100J Datasheet
292Kb / 16P
   HIGH SPEED 2K x 8 DUAL PORT STATIC RAM
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12


Datasheet Download

Go To PDF Page


Link URL




Privacy Policy
ALLDATASHEET.NET
Does ALLDATASHEET help your business so far?  [ DONATE ] 

About Alldatasheet   |   Advertisement   |   Contact us   |   Privacy Policy   |   Link Exchange   |   Manufacturer List
All Rights Reserved©Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com