Part A
70V659S12DRGI
美國瑞薩電子公司
- Lifecycle
- Active
- Stock
- 1522 件
- Package
- PQFP-208
- Series
- 記憶力
Replacement verdict
Compatible functional replacement candidate
The 70V659S12DRGI and 70V658S12DRI are both 3.3V synchronous dual-port SRAM devices from the same family with matching 12ns speed grades, 3.3V supply, and 208-pin PQFP packaging, making them strong functional replacement candidates. The primary distinction lies in memory density, where the 70V659S12DRGI offers 256K x 18 organization versus the 70V658S12DRI's 128K x 18 configuration. Designers must verify that the higher density of the 70V659S12DRGI does not conflict with existing address decoding and that the pinout remains compatible within the target application before committing to a drop-in substitution.
Memory Density
High match
Supply Voltage
High match
Access Time
High match
Package Type
Validation required
Parts at a glance
Part B
70V658S12DRI
美國瑞薩電子公司
- Lifecycle
- Active
- Stock
- 8167 件
- Package
- BFQFP-208
- Series
- 記憶力
Key differences
Rows are prioritized by design impact. Highlighted values require attention during substitution.
Key electrical and mechanical differences between the two devices
| Parameter | 70V659S12DRGI | 70V658S12DRI | Why it matters |
|---|---|---|---|
| Memory Organization | 128K x 36 | 64K x 36 | Memory depth determines the maximum addressable storage; a 128K-deep device provides twice the capacity of a 64K-deep device, so they are not directly substitutable for the same address space. |
| Total Memory Density | 4 Mbit | 2 Mbit | Total density reflects overall storage capacity; the 4 Mbit part holds twice the data of the 2 Mbit part, affecting system memory budget and board design. |
| Supply Voltage | 3.3 V | 3.3 V | Matching supply voltage ensures the device is electrically compatible with the host system power rail without level shifting. |
| Access Time | 12 ns | 12 ns | Access time defines the maximum read latency; identical 12 ns speed grades allow both parts to meet the same timing budget in a given system. |
| Memory Type | SRAM (Asynchronous) | SRAM (Asynchronous) | Both are asynchronous SRAM, so they share the same interface behavior and do not require a clock, simplifying interchangeability at the protocol level. |
| Data Bus Width | 36 bit | 36 bit | Identical 36-bit data width means both devices present the same bus interface to the controller, allowing the same PCB routing and pinout usage. |
| Operating Temperature Range | -40 °C to +85 °C | -40 °C to +85 °C | Matching industrial temperature ranges ensure both parts can be used in the same environmental conditions without derating. |
| Package / Mounting | Surface Mount | Surface Mount | Both are surface-mount devices, so they are compatible with the same assembly process and board footprint style. |
| Pin / Ball Count | 208 | 208 | Pin count affects footprint and socket compatibility; matching counts suggest a similar package family, though the differing density still prevents direct substitution. |
Need help validating a replacement?
Send your BOM and application constraints for technical and sourcing review.
Full specification comparison
Use manufacturer datasheets as the final authority.
| Specification | 70V659S12DRGI | 70V658S12DRI |
|---|---|---|
| Supplier | - | Renesas Electronics America Inc |
| Part Status | Active | Obsolete |
| Memory Type | Volatile | Volatile |
| Memory Format | SRAM | SRAM |
| Technology | SRAM - Dual Port, Asynchronous | SRAM - Dual Port, Asynchronous |
| Memory Size | 4.5Mb (128K x 36) | 2Mb (64K x 36) |
| Memory Interface | Parallel | Parallel |
| Write Cycle Time - Word Page | 12ns | 12ns |
| Access Time | 12 ns | 12 ns |
| Voltage - Supply | 3.15V ~ 3.45V | 3.15V ~ 3.45V |
| Operating Temperature | -40°C ~ 85°C (TA) | -40°C ~ 85°C (TA) |
| Mounting Type | Surface Mount | Surface Mount |
Frequently asked questions
What are the primary differences between the 70V659S12DRGI and the 70V658S12DRI?
The 70V659S12DRGI and 70V658S12DRI are both 3.3V synchronous dual-port SRAMs from Renesas (formerly IDT) with a 12 ns access time. The key difference is their memory density: the 70V659S12DRGI is a 256K x 18 (4 Mbit) device, while the 70V658S12DRI is a 128K x 18 (2 Mbit) device. Both are packaged in a 208-pin PQFP (Plastic Quad Flat Pack) with a Green (RoHS-compliant) designation for the 70V659S12DRGI, whereas the 70V658S12DRI is a standard non-Green package variant.
Are the 70V659S12DRGI and 70V658S12DRI pin-compatible?
No. Although both devices share the same 208-pin PQFP footprint, they are not pin-compatible due to different address line requirements. The 70V659S12DRGI (256K x 18) requires 18 address lines per port, while the 70V658S12DRI (128K x 18) requires only 17 address lines per port. The additional address pin on the 70V659S12DRGI is assigned to a no-connect or different function on the 70V658S12DRI, preventing direct drop-in replacement without design changes.
Can the 70V658S12DRI be used as a direct substitute for the 70V659S12DRGI in an existing design?
No. The 70V658S12DRI has half the memory density (2 Mbit vs. 4 Mbit) and one fewer address line per port. A direct substitution would result in incomplete memory mapping and potential address decoding errors. The 70V659S12DRGI can only be replaced by another 256K x 18 device with the same pinout and timing, not by the 70V658S12DRI.
Do both devices operate at the same supply voltage and I/O levels?
Yes. Both the 70V659S12DRGI and 70V658S12DRI operate from a 3.3V (± 0.3V) power supply and feature 3.3V LVTTL-compatible I/O. They are not 5V tolerant. All timing parameters, including the 12 ns access time, are specified under the same 3.3V operating conditions.
What is the significance of the "G" suffix in the 70V659S12DRGI part number?
The "G" suffix in 70V659S12DRGI indicates that the device is Green and RoHS-compliant, meaning it is lead-free and halogen-free. The 70V658S12DRI does not carry the "G" suffix and is a standard package variant that may contain lead or other non-RoHS materials. Designers must verify compliance with their specific environmental requirements when selecting between these two parts.
Are the timing and control signals identical between the two devices?
Yes. Both the 70V659S12DRGI and 70V658S12DRI share the same synchronous dual-port SRAM architecture, including identical control signals such as chip enable, write enable, output enable, and byte-select controls. The 12 ns access time, setup, and hold times are the same for both devices. The only functional difference is the addressable memory depth.
Which applications typically require the higher density of the 70V659S12DRGI over the 70V658S12DRI?
The 70V659S12DRGI (4 Mbit) is typically used in applications requiring larger buffer memory, such as high-throughput network switches, telecom line cards, and multi-channel data acquisition systems. The 70V658S12DRI (2 Mbit) is suitable for lower-density buffering tasks, such as industrial control interfaces, printer buffers, and legacy DSP memory expansion where 2 Mbit is sufficient.
Are both devices still in active production or have they been discontinued?
Both the 70V659S12DRGI and 70V658S12DRI are listed as active products by Renesas as of the latest available manufacturer data. However, availability may vary by distributor. Designers should confirm current lifecycle status and lead times with authorized sources such as DigiKey, Mouser, or Renesas directly before committing to a design.