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IDT70121S Datasheet, PDF (1/12 Pages) Integrated Device Technology – HIGH-SPEED 2K x 9 DUAL-PORT STATIC RAM WITH BUSY & INTERRUPT | |||
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Integrated Device Technology, Inc.
HIGH-SPEED
2K x 9 DUAL-PORT
STATIC RAM WITH BUSY & INTERRUPT
IDT70121S/L
IDT70125S/L
FEATURES:
⢠High-speed access
â Commercial: 25/35/45/55ns (max.)
⢠Low-power operation
â IDT70121/70125S
Active: 500mW (typ.)
Standby: 5mW (typ.)
â IDT70121/70125L
Active: 500mW (typ.)
Standby: 1mW (typ.)
⢠Fully asychronous operation from either port
⢠MASTER IDT70121 easily expands data bus width to 18
bits or more using SLAVE IDT70125 chip
⢠On-chip port arbitration logic (IDT70121 only)
⢠BUSY output flag on Master; BUSY input on Slave
⢠INT flag for port-to-port communication
⢠Battery backup operationâ2V data retention
⢠TTL-compatible, signal 5V (±10%) power supply
⢠Available in 52-pin PLCC
⢠Industrial temperature range (â40°C to +85°C) is avail-
able, tested to military electrical specifications
DESCRIPTION:
The IDT70121/IDT70125 are high-speed 2K x 9 Dual-Port
Static RAMs. The IDT70121 is designed to be used as a
stand-alone 9-bit Dual-Port RAM or as a âMASTERâ Dual-Port
RAM together with the IDT70125 âSLAVEâ Dual-Port in 18-
bit-or-more word width systems. Using the IDT MASTER/
SLAVE Dual-Port RAM approach in 18-bit-or-wider memory
system applications results in full-speed, error-free operation
without the need for additional discrete logic.
Both devices provide two independent ports with separate
control, address, and I/O pins that permit independent, asyn-
chronous access for reads or writes to any location in memory.
An automatic power-down feature, controlled by CE, permits
the on-chip circuitry of each port to enter a very low standby
power mode.
The IDT70121/IDT70125 utilizes a 9-bit wide data path to
allow for Data/Control and parity bits at the userâs option. This
feature is especially useful in data communications
applications where it is necessary to use a parity bit for
transmission/reception error checking.
FUNCTIONAL BLOCK DIAGRAM
OEL
CEL
R/ WL
OER
CER
R/WR
I/O0L- I/O8L
I/O
Control
I/O
Control
BUSYL(1,2)
A10L
A0L
Address
Decoder
MEMORY
ARRAY
Address
Decoder
11
NOTES:
1. 70121 (MASTER):
BUSY is non-tri-
stated push-pull
output.
70125 (SLAVE):
BUSY is input.
2. INT is totem-pole
output.
INTL(2)
CEL
OEL
R/ WL
The IDT logo is a registered trademark of Integrated Device Technology, Inc.
COMMERCIAL TEMPERATURE RANGE
ARBITRATION
INTERRUPT
SEMAPHORE
LOGIC
11
CER
OER
R/WR
©1996 Integrated Device Technology, Inc.
For latest information contact IDTâs web site at www.idt.com or fax-on-demand at 408-492-8391.
6.10
I/O0R-I/O 8R
BUSYR (1,2)
A11R
A0R
INTR (2)
2654 drw 01
OCTOBER 1996
DSC-2654/4
1
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