Renesas 7027S15PF

Overview

7027S15PF from IDT is a high-speed 32K × 16 dual-port static RAM with true simultaneous access to the same memory location from independent left and right ports, 15 ns maximum read cycle time (commercial grade), TTL-compatible 5 V ±10% supply, and integrated hardware semaphore and BUSY arbitration logic - used in real-time inter-processor communication systems requiring deterministic data exchange.

For engineers reviewing the 7027S15PF datasheet, 7027S15PF pinout, 7027S15PF application, or 7027S15PF equivalent, key selection criteria include port-to-port contention resolution timing (tBDD ≤15 ns), dual-chip-enable power-down control, M/S-selectable master/slave configuration for 32-bit bus expansion, and industrial-grade availability of compatible speed grades.

Technical Context

The 7027S15PF implements fully asynchronous dual-port architecture with separate address, control, and I/O buses per port, enabling concurrent read/write operations without external arbitration logic. Its on-chip arbitration uses address-match detection and CE timing to assert BUSY flags, with tAPS = 5 ns priority setup time ensuring deterministic resolution.

Hardware semaphore signaling operates via dedicated SEM pins and A0–A2 addressing of eight shared flags, accessible only when CE = VIH and SEM = VIL - distinct from main memory access (CE = VIL, SEM = VIH). Interrupt flags (INTL/INTR) are triggered by writes to fixed mailbox addresses (7FFE_H/7FFF_H) and cleared by subsequent reads or writes per Truth Table IV.

Key Specifications

Pinout & Package

7027S15PF is housed in a 100-pin Thin Quad Flatpack (TQFP) with 0.5 mm pitch, body size 14 mm × 14 mm × 1.4 mm. All VCC and GND pins require local decoupling; NC pins must remain unconnected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-15AXC and IDT70V27L15PF, the 7027S15PF uniquely integrates master/slave cascading and hardware semaphore - reducing BOM count and firmware complexity in tightly coupled multi-processor designs.

Availability

7027S15PF is available at Aetrix Electronics and suitable for real-time inter-processor communication, digital signal processing subsystems, and industrial PLC backplane interfaces requiring stable component supply and long-term obsolescence management.

Supply support for 7027S15PF 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 for communications, computing, and industrial markets.

The IDT7027 family was designed specifically for deterministic, low-latency inter-processor communication in multi-CPU systems - emphasizing hardware arbitration, semaphore support, and seamless bus expansion.

FAQ

What is the maximum operating frequency supported by the 7027S15PF?

The 7027S15PF has a 15 ns maximum read cycle time (tRC), supporting up to 66.7 MHz effective memory access rate. This is measured under commercial conditions (0°C to +70°C, VCC = 5.0 V ±10%) with all control signals meeting AC test conditions. The 7027S15PF does not specify a clock input; its operation is fully asynchronous, so timing depends on signal edge alignment rather than a system clock frequency.

How does the BUSY arbitration logic work in the 7027S15PF?

The 7027S15PF asserts BUSY when address or chip-enable signals match between ports, preventing simultaneous writes to the same location. With M/S = VIH (master mode), BUSYL/BUSYR are outputs that block the opposing port's write cycle until the current operation completes. The tBDD parameter (≤15 ns) defines the delay from BUSY deassertion to valid read data - ensuring deterministic resolution without software intervention. This logic is implemented entirely in hardware.

Can the 7027S15PF be used in a 32-bit data bus configuration?

Yes - the 7027S15PF supports 32-bit bus expansion via its Master/Slave (M/S) configuration. When cascading two devices, one is configured as master (M/S = VIH) and the other as slave (M/S = VIL); the master's BUSY output connects to the slave's BUSY input. This enables synchronized 32-bit word access without external logic, maintaining full 15 ns access speed across both devices as specified in the IDT7027 functional description.

What are the voltage levels required for the 7027S15PF control inputs?

The 7027S15PF requires TTL-compatible input thresholds: VIH ≥ 2.2 V (min), VIL ≤ 0.8 V (max) for all control pins (CE, R/W, OE, SEM, etc.), with VCC = 5.0 V ±10%. Input leakage is ≤10 µA over temperature. These levels ensure direct interfacing with 5 V microcontrollers and FPGAs without level-shifting. The 7027S15PF does not support 3.3 V logic inputs - applying voltages outside the specified range may cause undefined behavior or damage.

Does the 7027S15PF support byte-wide write operations?

Yes - the 7027S15PF provides independent upper-byte (UB/UBR) and lower-byte (LB/LBR) select controls per port. Asserting UBL = LBL = VIH disables both bytes; setting UBL = VIH and LBL = VIL enables write to lower byte only (I/O0–I/O7), and vice versa. This allows precise 8-bit updates without read-modify-write sequences - critical for peripheral register mapping and mixed-data-width systems using the 7027S15PF.