Renesas 70T633S12BCI

Overview

70T633S12BCI from IDT (now Renesas) is a high-speed 512K × 18-bit asynchronous dual-port static RAM with independent left/right ports, 12 ns max access time, 2.5 V core supply, and selectable 2.5 V/3.3 V I/O interface per port-used in real-time inter-processor communication, FPGA co-processing, and telecom packet buffering.

For engineers reviewing the 70T633S12BCI datasheet, 70T633S12BCI pinout, 70T633S12BCI application, or 70T633S12BCI equivalent, key selection criteria include true simultaneous dual-port access, on-chip semaphore arbitration, RapidWrite Mode for back-to-back writes, industrial temperature support (–40°C to +85°C), and BGA-256 package compatibility with JTAG IEEE 1149.1 testability.

Technical Context

This device implements fully asynchronous operation: each port has independent address, control (CE0/CE1, R/W, OE, UB/LB), and 18-bit bidirectional I/O buses. Port arbitration is handled internally via hardware semaphore logic supporting eight shared flags accessed via A0–A2.

It supports three power states: active (IDD ≤ 445 mA), standby (ISB2 ≤ 290 mA), and sleep mode (IZZ ≤ 20 mA) activated by ZZL/ZZR inputs. Core voltage is fixed at 2.5 V ±100 mV; I/O voltage per port is selected independently via OPTL/OPTR pins (2.5 V or 3.3 V).

Key Specifications

Pinout & Package

70T633S12BCI is housed in a 256-ball fine-pitch Ball Grid Array (BC256/BCG256) with 17 mm × 17 mm body and 1.0 mm ball pitch. All VDD pins require 2.5 V; VDDQ pins must match OPT pin configuration (2.5 V if OPT = VSS, 3.3 V if OPT = VDD).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-12BGXI, 70T633S12BCI delivers lower power via sleep mode and eliminates external logic with integrated semaphore and arbitration. Against AS7C35128P-12JIN, it provides true dual-port concurrency essential for real-time inter-processor communication.

Availability

70T633S12BCI is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, and medical imaging systems requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature performance.

Supply support for 70T633S12BCI 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), now part of Renesas Electronics, is a fabless semiconductor company specializing in high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.

The 70T633S12BCI belongs to IDT's high-speed asynchronous dual-port SRAM product line, designed specifically for deterministic, low-latency inter-processor communication in real-time embedded systems where concurrent access and hardware synchronization are critical.

FAQ

What is the maximum operating temperature range for the 70T633S12BCI?

The 70T633S12BCI is rated for industrial temperature operation from –40°C to +85°C. This specification applies across all DC and AC electrical parameters-including 12 ns access time, sleep mode current (≤20 mA), and JTAG functionality-ensuring reliable performance in harsh environments like base stations and factory controllers.

Does the 70T633S12BCI support both 2.5 V and 3.3 V I/O interfaces simultaneously?

Yes, the 70T633S12BCI supports mixed-voltage operation: OPTL and OPTR pins configure I/O voltage independently per port. Setting OPTL = VSS and OPTR = VDD configures left port for 2.5 V I/O and right port for 3.3 V I/O-enabling direct interfacing with heterogeneous SoCs without level shifters.

How does the RapidWrite Mode function in the 70T633S12BCI?

RapidWrite Mode in the 70T633S12BCI allows consecutive write cycles without toggling R/W or CE between addresses. The write cycle ends on the address transition-not R/W deassertion-reducing controller timing burden. It requires meeting tAAS ≤ 1 ns and tARF ≥ 1.5 V/ns to prevent spurious writes.

What is the role of the BUSY pin in master/slave configurations of the 70T633S12BCI?

In the 70T633S12BCI, the BUSY pin functions as an output when M/S = VIH (Master mode), signaling contention during concurrent access. When M/S = VIL (Slave mode), BUSY becomes an input-allowing daisy-chained arbitration where the Master asserts BUSY to stall Slave writes until completion.

Is JTAG boundary scan supported on the 70T633S12BCI, and what standard does it comply with?

Yes, the 70T633S12BCI supports full IEEE 1149.1-compliant JTAG boundary scan in its BGA-256 package. Pins TCK, TMS, TDI, TDO, and TRST are dedicated for test access; functionality remains active even during sleep mode (though not recommended for boundary scan execution in that state).