Renesas UPD44646363AF5-E22-FQ1

Overview

UPD44646363AF5-E22-FQ1 from Renesas Electronics is a 2,097,152-word × 36-bit synchronous double data rate (DDR II+) SRAM with 2.5 clock cycles read latency, HSTL interface, and 165-pin plastic BGA (15 × 17 mm) packaging. It operates at 1.8 V core supply, supports 450 MHz clock frequency (2.2 ns cycle time), and integrates DLL/PLL, on-die termination (ODT), QVLD, and echo clocks (CQ/CQ#) for high-speed memory subsystems in networking and test equipment.

For engineers reviewing the UPD44646363AF5-E22-FQ1 datasheet, UPD44646363AF5-E22-FQ1 pinout, UPD44646363AF5-E22-FQ1 application, or UPD44646363AF5-E22-FQ1 equivalent, this page delivers verified specifications, validated pin functions, confirmed DDR II+ timing behavior (2.5-cycle latency, burst-2 operation), ODT configuration constraints, and real-world use context - all extracted from Renesas' official M19960EJ2V0DS datasheet (2nd ed., March 2010).

Technical Context

This device implements pipelined DDR operation using dual-edge-triggered input clocks (K/K#) and edge-aligned echo clocks (CQ/CQ#) to deliver deterministic 2.5-cycle read latency. Its internal architecture includes a synchronous address register, burst counter, write driver, sense amplifiers, and output registers synchronized to K/K# rising edges.

The UPD44646363AF5-E22-FQ1 uses HSTL I/O with programmable output impedance (35–70 Ω) and user-selectable ODT (ON/OFF at power-on only). It supports clock-stop mode with 20 μs recovery and requires strict power sequencing (VSS → VDD → VDDQ → VREF) to initialize DLL/PLL and ODT correctly.

Key Specifications

Pinout & Package

UPD44646363AF5-E22-FQ1 is housed in a 165-pin plastic BGA (15 × 17 mm, 0.8 mm pitch), compatible with JEDEC MO-251AC. Pin assignment follows the x36 organization variant per Renesas datasheet Figure 3 (page 6), with dedicated DQ0–DQ35, BW0#–BW3#, and echo clock outputs CQ/CQ#.

Key Features

Applications

Equivalent & Alternatives

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

Compared with UPD44646363AF5-E22-FQ1, the Cypress alternative offers lower speed and no QVLD/ODT, increasing system design complexity; the ISSI part is asynchronous and incompatible with DDR timing requirements - neither provides the same combination of 450 MHz DDR II+, echo clocks, and integrated signal integrity features.

Availability

UPD44646363AF5-E22-FQ1 is available at Aetrix Electronics and suitable for networking line cards, high-speed test equipment, and medical imaging systems requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for UPD44646363AF5-E22-FQ1 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 is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for industrial, automotive, and communications markets.

The UPD44646363AF5-E22-FQ1 belongs to Renesas' DDR II+ SRAM product line, designed specifically for high-speed, low-latency memory buffering in synchronous systems demanding precise timing, signal integrity, and robust power sequencing.

FAQ

What is the exact read latency of UPD44646363AF5-E22-FQ1, and is it configurable?

The UPD44646363AF5-E22-FQ1 has a fixed 2.5 clock cycles read latency - not user-configurable. This value is hardwired per the DDR II+ specification and confirmed in Renesas' M19960EJ2V0DS datasheet (page 11, Truth Table). Attempting to operate with 2.0-cycle timing violates AC specifications and risks data corruption. The UPD44646363AF5-E22-FQ1 is part of the "AF5-E22" speed grade, explicitly rated for 2.5-cycle latency at 450 MHz.

Does UPD44646363AF5-E22-FQ1 support on-die termination (ODT), and how is it enabled?

Yes, UPD44646363AF5-E22-FQ1 supports ODT, but it is enabled only at power-on via the ODT pin. If ODT is HIGH before stable clock application, ODT activates with RTT = 0.6 × RQ (RQ = external ZQ resistor). Once initialized, ODT state cannot be changed. The UPD44646363AF5-E22-FQ1 requires RQ between 175 Ω and 350 Ω to guarantee ±20% impedance tolerance, as specified in the On-Die Termination DC Parameters table (page 10).

What are the power sequencing requirements for UPD44646363AF5-E22-FQ1?

UPD44646363AF5-E22-FQ1 requires strict power sequencing: apply VSS first, then VDD, then VDDQ (simultaneously with or after VREF), and finally VIN. VDD must be stable before VDDQ, and |VDDQ − VDD| must not exceed 0.5 V during ramp-up. Failure to follow this sequence risks undefined DLL/PLL lock or ODT initialization. The UPD44646363AF5-E22-FQ1 datasheet (page 9) specifies ≥20 μs of stable clock post-power-up for full initialization.

Can UPD44646363AF5-E22-FQ1 operate with a 1.5 V VDDQ supply?

Yes, UPD44646363AF5-E22-FQ1 supports VDDQ = 1.5 ± 0.1 V or 1.8 ± 0.1 V, as stated in the Feature Differences table (page 3) and DC Characteristics section. When using 1.5 V VDDQ, VREF must be set to 0.75 V (VDDQ/2), and all HSTL I/O thresholds scale accordingly. The UPD44646363AF5-E22-FQ1 maintains full 450 MHz operation and 2.5-cycle latency under either VDDQ condition, provided VDD remains at 1.8 ± 0.1 V.

What is the function of the QVLD pin on UPD44646363AF5-E22-FQ1, and how is it timed?

The QVLD pin on UPD44646363AF5-E22-FQ1 is a synchronous output that asserts high on the same rising edge of CQ/CQ# that coincides with valid DQ data. As defined in the Pin Identification table (page 7), QVLD is edge-aligned with CQ/CQ# - not with K/K#. This eliminates system-level timing uncertainty when latching DDR output data. The UPD44646363AF5-E22-FQ1 guarantees QVLD assertion within ±50 ps of CQ/CQ# edges under all operating conditions.