Renesas UPD44644182AF5-E40-FQ1-A

Overview

UPD44644182AF5-E40-FQ1-A from Renesas Electronics is a 4,194,304-word × 18-bit synchronous double data rate (DDR II) SRAM with HSTL interface, 4.0 ns clock cycle time (250 MHz), 1.8 V core supply, and 165-pin plastic BGA (15 × 17 mm) packaging. It supports pipelined DDR operation, two-tick burst, DLL/PLL timing control, and user-programmable output impedance (35–70 Ω), targeting high-speed memory buffering in telecom and networking equipment.

For engineers reviewing the UPD44644182AF5-E40-FQ1-A datasheet, UPD44644182AF5-E40-FQ1-A pinout, UPD44644182AF5-E40-FQ1-A application, or UPD44644182AF5-E40-FQ1-A equivalent, key selection criteria include its 4M×18 organization, HSTL I/O compatibility, 250 MHz DDR timing, burst-2 synchronous access, and JTAG 1149.1 test port support for system-level validation.

Technical Context

This DDR II SRAM uses full-CMOS six-transistor memory cells and integrates synchronous peripheral circuitry including a burst counter, DLL/PLL for wide output data valid window, and echo clocks (CQ/CQ#) tightly matched to data outputs. All inputs are registered on the rising edges of complementary input clocks K/K#, while outputs are synchronized to C/C# or fall back to K/K# when C/C# are held high.

The device implements internally self-timed write control, clock-stop capability (20 μs recovery), and programmable output impedance via ZQ calibration. Its 18-bit bidirectional data bus (DQ0–DQ17) supports byte-write control via BW0#/BW1#, and address A0 enables random burst-start alignment - all operating under strict HSTL Class I DC/AC specifications and JEDEC-compliant timing constraints.

Key Specifications

Pinout & Package

UPD44644182AF5-E40-FQ1-A is housed in a 165-pin plastic BGA (15 × 17 mm, 0.8 mm pitch) with standard top-side marking and index corner. Pin functions follow JEDEC-compliant HSTL signaling conventions and include dedicated echo clocks (CQ/CQ#), dual input/output clocks (K/K#, C/C#), and byte-write controls (BW0#, BW1#).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C2665KV18 and IS42S16400F, UPD44644182AF5-E40-FQ1-A uniquely combines HSTL I/O, echo-clock timing, and on-die impedance tuning - making it optimal for high-reliability, low-jitter DDR II buffering where signal integrity and deterministic timing dominate cost or density considerations.

Availability

UPD44644182AF5-E40-FQ1-A is available at Aetrix Electronics and suitable for telecom infrastructure, network packet processing, and high-speed test equipment requiring stable component supply, long-lifecycle support, and guaranteed traceable sourcing.

Supply support for UPD44644182AF5-E40-FQ1-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 is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for automotive, industrial, and communications markets.

UPD44644182AF5-E40-FQ1-A belongs to Renesas' DDR II SRAM product line, engineered specifically for high-speed, low-latency synchronous buffering in telecom and networking systems demanding HSTL compatibility and precise timing control.

FAQ

What is the maximum operating frequency supported by UPD44644182AF5-E40-FQ1-A?

UPD44644182AF5-E40-FQ1-A supports a maximum clock cycle time of 4.0 ns, corresponding to 250 MHz DDR operation (500 MT/s effective data rate). While the device family also offers 3.3 ns (300 MHz) and 5.0 ns (200 MHz) variants, this specific part is rated for 250 MHz under standard operating conditions (TA = 0–70°C, VDD = 1.8 ± 0.1 V).

Does UPD44644182AF5-E40-FQ1-A require external termination resistors?

No - UPD44644182AF5-E40-FQ1-A features user-programmable output impedance (35–70 Ω) calibrated via the ZQ pin and an external resistor to ground. This eliminates the need for discrete series termination resistors on DQ, CQ, and CQ# lines, simplifying PCB layout and improving signal integrity across voltage and temperature variations.

How does the burst-2 operation work in UPD44644182AF5-E40-FQ1-A?

UPD44644182AF5-E40-FQ1-A performs fixed 2-word linear bursts. When LD# goes low and R,W# is sampled, the internal burst counter advances A0 to generate the second address. Data appears on DQ0–DQ17 in two consecutive cycles aligned to C#/C rising edges - reducing command overhead and enabling predictable latency for streaming applications.

Can UPD44644182AF5-E40-FQ1-A operate without the DLL/PLL enabled?

Yes - pulling DLL# low disables the DLL/PLL, allowing operation at frequencies below 120 MHz using basic clock-edge registration. However, AC/DC characteristics are not guaranteed in this mode. For full specification compliance at 250 MHz, DLL# must be tied HIGH (e.g., to VDDQ via ≤10 kΩ resistor) to engage the timing circuitry.

What is the role of the CQ and CQ# pins on UPD44644182AF5-E40-FQ1-A?

CQ and CQ# are synchronous echo clock outputs on UPD44644182AF5-E40-FQ1-A, whose rising edges are tightly matched (<100 ps skew) to the corresponding DQ data outputs. They provide a hardware-valid timing reference for the receiving device - enabling precise capture without requiring complex deskew algorithms or external delay elements.