Features: • FT pin for user-configurable flow through or pipeline operation
• Single Cycle Deselect (SCD) operation
• 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 availableApplicationThe GS8640V18/32/36T is a 75,497,472-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.
Pinout
Specifications
| Symbol |
Description |
Value |
Unit |
| VDD |
Voltage on VDD Pins |
0.5 to 3.6 |
V |
| VDDQ |
Voltage in VDDQ Pins |
0.5 to 3.6 |
V |
| VI/O |
Voltage on I/O Pins |
0.5 to VDDQ +0.5 ( 3.6 V max.) |
V |
| VIN |
Voltage on Other Input Pins |
0.5 to VDD +0.5 ( 3.6 V max.) |
V |
| IIN |
Input Current on Any Pin |
+/20 |
mA |
| IOUT |
Output Current on Any I/O Pin |
+/20 |
mA |
| PD |
Package Power Dissipation |
1.5 |
W |
| TSTG |
Storage Temperature |
55 to 125 |
|
| TBIAS |
Temperature Under Bias |
55 to 125 |
|
Note:
Permanent damage to the device may occur if the Absolute Maximum Ratings are exceeded. Operation should be restricted to Recommended Operating Conditions. Exposure to conditions exceeding the Absolute Maximum Ratings, for an extended period of time, may affect reliability of this component.
DescriptionApplications
The GS8640V18/32/36T is a 75,497,472-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 GS8640V18/32/36T now finds application in synchronous SRAM applications, ranging from DSP main store to networking chip set support.
Controls
Addresses, data I/Os, chip enables (E1, E2, E3), 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 of GS8640V18/32/36T 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 either linear or interleave order with the Linear Burst Order (LBO) input. The Burst function of GS8640V18/32/36T 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 GS8640V18/32/36T 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 risingedge- triggered Data Output Register.
Byte Write and Global Write
Byte write operation of GS8640V18/32/36T 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) of GS8640V18/32/36T 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 GS8640V18/32/36T operates on a 1.8 V power supply. All input are 1.8 V compatible. Separate output power (VDDQ) pins are used to decouple output noise from the internal circuits and are 1.8 V compatible.
GS8640V18 Data Sheet
