Renesas UPD46364365BF1-E40-EQ1-A

Overview

UPD46364365BF1-E40-EQ1-A from NEC Electronics (now Renesas) is a 1,048,576-word × 36-bit synchronous double data rate static RAM with HSTL interface, 4.0 ns clock cycle time (250 MHz), 1.8 V core supply, and 165-pin plastic BGA (13 × 15) packaging. It delivers pipelined DDR read/write operations per cycle for high-bandwidth buffering in network packet processors and FPGA co-processor memory subsystems.

For engineers reviewing the UPD46364365BF1-E40-EQ1-A datasheet, UPD46364365BF1-E40-EQ1-A pinout, UPD46364365BF1-E40-EQ1-A application, or UPD46364365BF1-E40-EQ1-A equivalent, key selection considerations include its 2-word burst architecture, separate I/O ports, user-programmable output impedance (35–70 Ω), echo clock (CQ/CQ#) timing alignment, and JTAG 1149.1 test port support.

Technical Context

This DDR II SRAM uses full-CMOS six-transistor memory cells and integrates a PLL-based timing engine that locks to K/K# input clocks to widen the output data valid window and enable future frequency scaling. Its dual-clock architecture separates input registration (K/K#) from output timing (C/C# or K/K#), allowing precise flight-time matching between clock and data paths.

The device implements synchronous load (LD#) control to define address and R/W direction per burst, supports byte-write masking via BW0#–BW3#, and features internally self-timed write control with clock-stop capability (20 μs recovery). All I/Os conform to JEDEC HSTL Class I standards with VREF-referenced inputs and programmable output termination via ZQ calibration.

Key Specifications

Pinout & Package

165-pin plastic BGA (13 × 15 mm), top view, with index mark per package dimensions. Ball pitch: 0.8 mm. Thermal pad: none. RoHS-compliant lead-free finish (per EQ1-A suffix).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR II SRAM applications.

Compared with CY7C1551KV18-400BZI and IS42S32800F-6BL, UPD46364365BF1-E40-EQ1-A provides native 36-bit width and deterministic DDR II SRAM timing without refresh overhead, making it optimal for latency-critical, burst-oriented buffering where bus efficiency and timing predictability are prioritized over raw peak bandwidth.

Availability

UPD46364365BF1-E40-EQ1-A is available at Aetrix Electronics and suitable for network packet buffering, FPGA co-processor memory, baseband signal processing, and real-time video frame buffering requiring stable component supply across industrial temperature ranges (0°C to 70°C).

Supply support for UPD46364365BF1-E40-EQ1-A 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

Renesas Electronics Corporation (formerly NEC Electronics) is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for automotive, industrial, and infrastructure markets.

The μPD46364xxx DDR II SRAM product line was designed specifically for high-speed, low-latency buffering in communications infrastructure and programmable logic systems requiring deterministic burst access and HSTL-compatible signaling.

FAQ

What is the maximum guaranteed clock frequency for UPD46364365BF1-E40-EQ1-A?

The UPD46364365BF1-E40-EQ1-A is rated for a 4.0 ns clock cycle time, supporting guaranteed operation at 250 MHz across the full commercial temperature range (0°C to 70°C). This rating is validated per AC Characteristics Table on page 17 of R10DS0092EJ0400 Rev.4.00. Operation above 250 MHz requires the -E33 variant (3.3 ns, 300 MHz).

Does UPD46364365BF1-E40-EQ1-A require external termination resistors?

No. UPD46364365BF1-E40-EQ1-A supports on-die termination via the ZQ pin. Connecting ZQ to a precision resistor (175–350 Ω) to ground calibrates Q, CQ, and CQ# output impedance to 35–70 Ω, eliminating the need for external series or parallel termination resistors on data and echo clock lines.

How does the echo clock (CQ/CQ#) function in UPD46364365BF1-E40-EQ1-A?

The CQ and CQ# outputs in UPD46364365BF1-E40-EQ1-A are synchronous echo clocks tightly matched to data outputs (±0.1 ns variation). They provide a hardware-valid timing reference independent of C/C# state and remain active even when Q outputs are tristated, enabling robust data capture in high-speed receivers without relying solely on C/C#.

Can UPD46364365BF1-E40-EQ1-A operate without the PLL enabled?

Yes. Pulling DLL# low disables the PLL, allowing operation at reduced clock frequencies (<120 MHz) for debug or low-power modes. However, AC/DC characteristics are not guaranteed in this mode, and read latency changes to 1.0 clock cycle. For production operation, DLL# must be tied HIGH (e.g., to VDDQ via ≤10 kΩ resistor).

What is the purpose of the LD# (Load) signal in UPD46364365BF1-E40-EQ1-A?

The LD# signal in UPD46364365BF1-E40-EQ1-A is a synchronous load strobe that defines the start of each 2-word burst transaction. When asserted low, it latches the current address and R/W# state, initiating either a read or write burst. It replaces conventional address strobes and simplifies controller logic by embedding burst definition into a single control signal.