Renesas 7028L15PFG8

Overview

7028L15PFG8 from IDT (Integrated Device Technology) is a high-speed 64K × 16 true dual-ported static RAM with independent left/right ports, 15 ns max access time (commercial grade), TTL-compatible 5V ±10% supply, and integrated hardware semaphore/arbiter logic for inter-processor communication in real-time embedded systems.

For engineers reviewing the 7028L15PFG8 datasheet, 7028L15PFG8 pinout, 7028L15PFG8 application, or 7028L15PFG8 equivalent, this device supports simultaneous asynchronous reads/writes across ports, BUSY-flag arbitration, interrupt signaling via FFFE/FFFF mailbox addresses, and byte-selectable I/O control - critical for deterministic multi-CPU memory sharing.

Technical Context

The 7028L15PFG8 implements fully asynchronous dual-port operation with separate address, data, and control buses per port (A0L–A15L/I/O0L–I/O15L vs A0R–A15R/I/O0R–I/O15R), enabling concurrent access without internal clocking. Its on-chip arbitration logic uses push-pull BUSYL/BUSYR flags (not open-drain) to signal address contention, with tBDD ≤15 ns propagation delay from write completion to valid read data under master mode (M/S = VIH).

Hardware semaphore functionality operates independently of the main memory array using eight dedicated latches addressed by A0–A2, accessible only when CE = VIH and SEM = VIL; semaphore writes occur via I/O0, while reads return the flag value across all 16 I/O lines. Interrupt generation is triggered by writes to fixed mailbox addresses FFFE_H (left port sets INTR) and FFFF_H (right port sets INTL), with tINS ≤15 ns setup time.

Key Specifications

Pinout & Package

7028L15PFG8 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 pins require connection to 5V supply; all GND pins must be grounded.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C028V-15ZXI and IS61WV6416BLL-15TLI, the 7028L15PFG8 uniquely delivers hardware semaphore arbitration, 5V compatibility, and push-pull BUSY signaling - eliminating external logic and reducing system-level latency in real-time multi-processor architectures.

Availability

7028L15PFG8 is available at Aetrix Electronics and suitable for industrial PLC communication hubs, real-time radar signal processors, automotive ADAS domain controllers, and telecom baseband modems requiring stable component supply and long-term production continuity.

Supply support for 7028L15PFG8 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 timing, memory, and interface solutions for communications, computing, and industrial markets before its acquisition by Renesas Electronics in 2019.

The 7028L15PFG8 belongs to IDT's legacy high-speed dual-port SRAM product line, engineered specifically for deterministic inter-processor communication in real-time embedded systems requiring hardware-enforced resource arbitration.

FAQ

What is the maximum operating frequency supported by the 7028L15PFG8?

The 7028L15PFG8 supports a maximum read cycle time (tRC) of 15 ns, enabling reliable operation at up to 67 MHz per port under commercial temperature conditions (0°C to +70°C). This frequency applies independently to left and right ports due to fully asynchronous design - no shared clock limits throughput. The 7028L15PFG8 does not specify a minimum cycle time for sustained operation, and timing parameters assume proper signal integrity and load conditions per AC Test Conditions (Figure 1/2).

How does the BUSY arbitration logic function in master versus slave configuration?

In master mode (M/S = VIH), BUSYL and BUSYR are push-pull outputs that assert low when address contention occurs, internally gating write signals to prevent corruption. In slave mode (M/S = VIL), BUSYL and BUSYR become inputs that must be held high for normal operation or pulled low to disable writes unconditionally. The 7028L15PFG8's BUSY logic requires no external pull-ups in master mode and supports depth expansion via external AND gates for array-level arbitration.

Can the 7028L15PFG8 be used in systems requiring both 5V and 3.3V interfaces?

No - the 7028L15PFG8 is strictly a 5V ±10% device (VCC = 4.5 V to 5.5 V) with TTL-compatible input thresholds (VIH ≥ 2.2 V, VIL ≤ 0.8 V). It lacks 3.3V I/O tolerance or level-shifting capability. Interfacing with 3.3V processors requires external voltage translators or bus buffers; direct connection risks overvoltage damage to downstream 3.3V components and violates absolute maximum ratings (VTERM ≤ 7.0 V).

What memory addresses are reserved for interrupt and semaphore functionality in the 7028L15PFG8?

The 7028L15PFG8 reserves address FFFE_H to set the right-port interrupt flag (INTR) and FFFF_H to set the left-port flag (INTL); clearing occurs via read access to those same locations. Semaphores occupy eight dedicated locations addressed by A0–A2 (000₂ to 111₂) and are accessed only when CE = VIH and SEM = VIL - separate from the main 64K × 16 memory map. These reserved functions are hardwired and cannot be relocated.

Does the 7028L15PFG8 support byte-wide writes without affecting adjacent bytes?

Yes - the 7028L15PFG8 provides independent upper-byte (UB/UBR) and lower-byte (LB/LBR) select controls per port. When UB = L and LB = H, only I/O8–I/O15 are written; when UB = H and LB = L, only I/O0–I/O7 are written; when both are low, all 16 bits update atomically. This enables precise 8-bit peripheral register updates without read-modify-write cycles or data corruption risk.