Renesas 70V27S20PF

Overview

70V27S20PF from Integrated Device Technology is a high-speed 3.3V 32K × 16 dual-ported static RAM with true simultaneous access to the same memory location, 20 ns maximum access time (commercial grade), 500 mW typical active power, and 100-pin TQFP package. It enables full-speed error-free 32-bit memory expansion via Master/Slave cascading in real-time control and communication subsystems.

For engineers reviewing the 70V27S20PF datasheet, 70V27S20PF pinout, 70V27S20PF application, or 70V27S20PF equivalent, key selection criteria include port arbitration timing (tAPS = 5 ns), BUSY flag behavior under address-match arbitration, semaphore support for inter-processor synchronization, and LVTTL-compatible 3.3V ±0.3V single-supply operation.

Technical Context

The 70V27S20PF implements fully asynchronous dual-port architecture with independent left/right address, control, and I/O buses. Each port features separate CE0/CE1, R/W, OE, UB/LB, SEM, INT, and BUSY signals, enabling concurrent read/write operations without external arbitration logic.

On-chip hardware supports semaphore signaling across ports using A0–A2 addressing of eight shared flags, and automatic power-down is triggered by TTL- or CMOS-level chip enable states. BUSY arbitration operates in two modes: address-match (tBAA ≤ 20 ns) or chip-enable-driven (tBAC ≤ 20 ns), with priority resolution set by tAPS = 5 ns.

Key Specifications

Pinout & Package

70V27S20PF is housed in a 100-pin TQFP (PN100-1) with 0.5 mm pitch, 14 mm × 14 mm body, and 1.4 mm height. All VDD pins require local decoupling; all VSS pins must be connected to ground plane.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-20AXC and R1EX24032AS0C-20#U0, the 70V27S20PF uniquely delivers integrated semaphore logic and address-match BUSY arbitration in a 100-pin TQFP, reducing BOM count and eliminating timing-critical software synchronization in real-time embedded systems.

Availability

70V27S20PF is available at Aetrix Electronics and suitable for industrial PLC memory buffers, telecom line card packet buffers, avionics display frame buffers, and medical imaging data pipelines requiring stable component supply and long-term production continuity.

Supply support for 70V27S20PF 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

Integrated Device Technology (IDT), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, and RF solutions for communications, computing, and industrial markets.

The IDT70V27 family was designed specifically for high-reliability dual-processor and FPGA-CPU co-processing systems requiring deterministic memory access, hardware interlock, and low-latency inter-core communication.

FAQ

What is the operating temperature range for the 70V27S20PF?

The 70V27S20PF is rated for commercial temperature operation from 0°C to +70°C. It is not qualified for industrial (-40°C to +85°C) use - that capability applies only to the 'L' variant (e.g., 70V27L20PF) and select speed grades. The 'S' suffix denotes standard power consumption and commercial temperature grade.

How does the BUSY arbitration work when both ports access the same address simultaneously on the 70V27S20PF?

When both ports attempt access to the same memory location, the 70V27S20PF uses address-match arbitration: the port whose address and control signals stabilize first asserts BUSY on the opposing port. The tAPS parameter (5 ns minimum setup) determines priority resolution; if violated, arbitration outcome is undefined. BUSY is push-pull, not open-drain.

Can the 70V27S20PF be used in a 32-bit data path configuration?

Yes - the 70V27S20PF supports 32-bit expansion via Master/Slave cascading. One device is configured as Master (M/S = VIH) providing BUSY output, another as Slave (M/S = VIL) accepting BUSY input. This enables synchronous 32-bit access without external glue logic, as documented in the functional description and truth tables.

What is the purpose of the SEM pin on the 70V27S20PF, and how is it used?

The SEM (Semaphore Enable) pin on the 70V27S20PF activates hardware semaphore register access. When SEM = VIL and CE = VIH, the device enters semaphore mode: A0–A2 select one of eight flags, and I/O0 writes the flag value while all I/O lines (I/O0–I/O15) read it back. This provides atomic inter-processor signaling without software intervention.

Does the 70V27S20PF support partial-byte writes, and how is this implemented?

Yes - the 70V27S20PF supports independent upper- and lower-byte writes using UBL/UBR and LBL/LBR pins. When UB = LOW and LB = HIGH, only I/O8–I/O15 are written; when UB = HIGH and LB = LOW, only I/O0–I/O7 are written. This enables precise data alignment in mixed-width bus systems without read-modify-write cycles.