Preliminary
GS8161EV18B(T/D)/GS8161EV32B(D)/GS8161EV36B(T/D)
100-Pin TQFP & 165-Bump BGA
Commercial Temp
Industrial Temp
Features
• FT pin for user-configurable flow through or pipeline
operation
• Dual Cycle Deselect (DCD) operation
• IEEE 1149.1 JTAG-compatible Boundary Scan
• 1.8 V +10%/–10% core power supply
• 1.8 V I/O supply
• LBO pin for Linear or Interleaved Burst mode
• Internal input resistors on mode pins allow floating mode pins
• Default to Interleaved Pipeline mode
• Byte Write (BW) and/or Global Write (GW) operation
• Internal self-timed write cycle
• Automatic power-down for portable applications
• JEDEC-standard 100-lead TQFP package
• Pb-Free 100-lead TQFP package available
1M x 18, 512K x 36, 512K x 36
18Mb Sync Burst SRAMs
250 MHz–150 MHz
1.8 V V
DD
1.8 V I/O
either linear or interleave order with the Linear Burst Order (LBO)
input. The Burst function need not be used. New addresses can be
loaded on every cycle with no degradation of chip performance.
Flow Through/Pipeline Reads
The function of the Data Output register can be controlled by the
user via the FT mode pin (Pin 14). Holding the FT mode pin low
places the RAM in Flow Through mode, causing output data to
bypass the Data Output Register. Holding FT high places the
RAM in Pipeline mode, activating the rising-edge-triggered Data
Output Register.
DCD Pipelined Reads
The
GS8161EV18B(T/D)/GS8161EV32B(D)/GS8161EV36B(T/D)
is a DCD (Dual Cycle Deselect) pipelined synchronous SRAM.
SCD (Single Cycle Deselect) versions are also available. DCD
SRAMs pipeline disable commands to the same degree as read
commands. DCD RAMs hold the deselect command for one full
cycle and then begin turning off their outputs just after the second
rising edge of clock.
Byte Write and Global Write
Byte write operation is performed by using Byte Write enable
(BW) input combined with one or more individual byte write
signals (Bx). In addition, Global Write (GW) is available for
writing all bytes at one time, regardless of the Byte Write control
inputs.
Sleep Mode
Low power (Sleep mode) is attained through the assertion (High)
of the ZZ signal, or by stopping the clock (CK). Memory data is
retained during Sleep mode.
Core and Interface Voltages
The
GS8161EV18B(T/D)/GS8161EV32B(D)/GS8161EV36B(T/D)
operates on a 1.8 V power supply. All input are 1.8 V compatible.
Separate output power (V
DDQ
) pins are used to decouple output
noise from the internal circuits and are 1..8 V compatible.
Functional Description
Applications
The
GS8161EV18B(T/D)/GS8161EV32B(D)/GS8161EV36B(T/D)
is a 18,874,368-bit high performance synchronous SRAM with a
2-bit burst address counter. Although of a type originally
developed for Level 2 Cache applications supporting high
performance CPUs, the device now finds application in
synchronous SRAM applications, ranging from DSP main store to
networking chip set support.
Controls
Addresses, data I/Os, chip enable (E1), address burst control
inputs (ADSP, ADSC, ADV) and write control inputs (Bx, BW,
GW) are synchronous and are controlled by a positive-edge-
triggered clock input (CK). Output enable (G) and power down
control (ZZ) are asynchronous inputs. Burst cycles can be initiated
with either ADSP or ADSC inputs. In Burst mode, subsequent
burst addresses are generated internally and are controlled by
ADV. The burst address counter may be configured to count in
Parameter Synopsis
-250
Pipeline
3-1-1-1
t
KQ
tCycle
Curr
(x18)
Curr
(x32/x36)
t
KQ
tCycle
Curr
(x18)
Curr
(x32/x36)
2.5
4.0
280
330
5.5
5.5
210
240
-200
3.0
5.0
230
270
6.5
6.5
185
205
-150
3.8
6.7
185
210
7.5
7.5
170
190
Unit
ns
ns
mA
mA
ns
ns
mA
mA
Flow Through
2-1-1-1
Rev: 1.00 9/2004
1/34
© 2004, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
Preliminary
GS8161EV18B(T/D)/GS8161EV32B(D)/GS8161EV36B(T/D)
TQFP Pin Description
Symbol
A
0
, A
1
A
DQ
A
DQ
B
DQ
C
DQ
D
NC
BW
B
A
, B
B,
B
C
, B
D
CK
GW
E
1
G
ADV
ADSP, ADSC
ZZ
LBO
TMS
TDI
TDO
TCK
V
DD
V
SS
V
DDQ
Type
I
I
I/O
—
I
I
I
I
I
I
I
I
I
I
I
I
O
I
I
I
I
Description
Address field LSBs and Address Counter preset Inputs
Address Inputs
Data Input and Output pins
No Connect
Byte Write—Writes all enabled bytes; active low
Byte Write Enable for DQ
A
, DQ
B
Data I/Os; active low
Clock Input Signal; active high
Global Write Enable—Writes all bytes; active low
Chip Enable; active low
Output Enable; active low
Burst address counter advance enable; active low
Address Strobe (Processor, Cache Controller); active low
Sleep Mode control; active high
Linear Burst Order mode; active low
Scan Test Mode Select
Scan Test Data In
Scan Test Data Out
Scan Test Clock
Core power supply
I/O and Core Ground
Output driver power supply
Rev: 1.00 9/2004
4/34
© 2004, GSI Technology
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.