Renesas 709279L15PF8

Overview

709279L15PF8 from IDT is a high-speed 32K × 16-bit synchronous dual-port static RAM with true dual-ported memory cells enabling simultaneous access to the same address from left and right ports, 15ns pipelined clock-to-data access, 25ns flow-through access, and industrial temperature support (–40°C to +85°C) in a 100-pin TQFP package. It serves as shared memory buffer in real-time DSP co-processing systems.

For engineers reviewing the 709279L15PF8 datasheet, 709279L15PF8 pinout, 709279L15PF8 application, or 709279L15PF8 equivalent, key selection criteria include pipelined vs. flow-through output mode configuration via FT/PIPE pin, dual chip enable for depth expansion without external logic, and TTL-compatible 5V ±10% operation with separate upper/lower byte controls.

Technical Context

The 709279L15PF8 implements fully synchronous operation on both ports with 4ns setup and 1ns hold times on all control, address, and data inputs. Its internal architecture includes dual address/data/control registers per port, self-timed write logic, and independent address counters with CNTEN/CNTRST control.

It supports two distinct output modes: pipelined (9ns tCD2, 15ns tCYC2, 67MHz max) and flow-through (30ns tCD1, 35ns tCYC1), selected per port by the FT/PIPE pin. The device uses CMOS high-performance fabrication and features automatic power-down via CE0/CE1 to achieve 1mW standby current in low-power (L) variant.

Key Specifications

Pinout & Package

100-pin TQFP (PN100) package, 14mm × 14mm × 1.4mm body, with 4×25 pin grid; all VCC pins must be decoupled locally, all GND pins tied to solid ground plane.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous dual-port SRAM applications.

Compared with CY7C028V-15AXC and IDT70V9279L15PF, the 709279L15PF8 offers native 5V TTL compatibility, industrial temperature rating, and direct support for legacy 5V controller interfaces-making it optimal for retrofit and high-reliability 5V systems where voltage translation adds risk.

Availability

709279L15PF8 is available at Aetrix Electronics and suitable for telecom infrastructure, industrial motion control, avionics data acquisition, and real-time DSP co-processing applications requiring stable component supply and long-term lifecycle assurance.

Supply support for 709279L15PF8 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

IDT (Integrated Device Technology) is a fabless semiconductor company specializing in high-performance memory, timing, and interface solutions, acquired by Renesas Electronics in 2019.

The IDT709279 family was designed specifically for deterministic, low-latency inter-processor communication in real-time embedded systems-emphasizing simultaneous dual-port access, configurable output timing, and industrial-grade reliability.

FAQ

What is the maximum operating frequency of the 709279L15PF8 in pipelined mode?

The 709279L15PF8 achieves a maximum operating frequency of 67MHz in pipelined output mode, derived from its 15ns clock cycle time (tCYC2). This specification is guaranteed over the full industrial temperature range (–40°C to +85°C) and 5.0V ±10% supply, with timing validated under AC test conditions including 30pF load and 3ns max clock rise/fall times. The 709279L15PF8 maintains this performance without derating in compliant PCB layouts.

Does the 709279L15PF8 support independent address counters on both ports?

Yes, the 709279L15PF8 provides fully independent address counters for left and right ports, each controlled by dedicated CNTENL/CNTRSTL and CNTENR/CNTRSTR pins. When CNTENX is asserted low on the rising clock edge, the corresponding port's internal address increments automatically-enabling burst transfers without external address generation. The 709279L15PF8 resets both counters to address 0 upon assertion of CNTRSTX, ensuring deterministic initialization.

How does the FT/PIPE pin affect timing behavior of the 709279L15PF8?

The FT/PIPE pin configures output timing mode per port: when driven LOW, the 709279L15PF8 operates in flow-through mode (tCD1 = 30ns max), delivering data coincident with clock edge; when HIGH, it enters pipelined mode (tCD2 = 15ns max), introducing one-cycle latency for higher throughput. Critically, the 709279L15PF8 treats FT/PIPE as a DC signal-mode changes require stable assertion before clocking begins, and mixing modes across ports is fully supported.

Can the 709279L15PF8 be used in depth-expanded memory configurations without external logic?

Yes, the 709279L15PF8 supports depth expansion without external logic using its dual chip enables (CE0X and CE1X per port). By tying CE0L=LOW/CE1L=HIGH for Bank 1 and CE0R=LOW/CE1R=HIGH for Bank 2 while sharing address/data buses, the 709279L15PF8 enables seamless 64K×16 expansion. Truth Table I in the datasheet confirms this configuration yields independent port selection, and the 709279L15PF8's identical pinout across variants ensures mechanical compatibility.

What is the standby power consumption of the 709279L15PF8, and how is it achieved?

The 709279L15PF8 consumes 1mW typical standby power (ISB3), achieved when both CE0 and CE1 are driven HIGH on a given port-disabling internal circuitry including registers and memory array drivers. This low-power state is maintained across the full industrial temperature range and requires no additional control signals. The 709279L15PF8's CMOS process and optimized gating logic ensure this 1mW figure remains stable even with TTL-level inputs held static.