NXP Semiconductors NE57814DD,518

Overview

NE57814DD,518 from NXP Semiconductors (formerly Philips) is a DDR memory termination regulator with integrated VTT and RefOut outputs, designed for precise ½×VDD termination voltage generation in DDR SDRAM systems. It delivers ±15 mV output voltage accuracy, supports ±3.5 A peak current, operates from 1.6 V to 3.6 V VDD, and features active-low STANDBY control for <1.35 mA quiescent current - enabling energy-efficient laptop and server memory subsystems.

For engineers reviewing the NE57814DD,518 datasheet, NE57814DD,518 pinout, NE57814DD,518 application, or NE57814DD,518 equivalent, key selection criteria include VTT accuracy under dynamic load (±6 mV load regulation at ±1 A), thermal resistance (38.5 °C/W on JEDEC 4-layer PCB), VD pin headroom optimization for efficiency, and cascading capability via RefOut/ExtRefIn for multi-DIMM systems.

Technical Context

The NE57814DD,518 implements a high-bandwidth linear regulator architecture with internal 100 kΩ resistor divider to maintain VTT = VDD/2, while supporting external reference override via ExtRefIn (0.8 V to VDD–0.8 V). Its power stage uses a low-Rds(on) (0.18 Ω typ.) MOSFET sourced from VD, enabling up to 82.5% sourcing efficiency when VD is only +0.25 V above VTT.

It integrates over-temperature shutdown (+150 °C trip, 20 °C hysteresis) and over-current protection (4.5 A typ. limit), and provides remote sensing via VTT SENSE pin connected directly to VTT output. The STANDBY pin (active-low) 3-states VTT while keeping RefOut active - critical for DDR self-refresh and low-power states.

Key Specifications

Pinout & Package

NE57814DD,518 is housed in an HSO8 (SOT786-2) thermally enhanced plastic small-outline package with 8 leads, 3.9 mm body width, and exposed die pad electrically tied to VSS - requiring dedicated thermal pad layout per JEDEC JESD51-7 for rated 38.5 °C/W performance.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar DDR memory termination regulator applications.

Compared with TPS51100PWP and ISL6537CRZ, the NE57814DD,518 uniquely combines VD-based efficiency optimization, RefOut-driven cascading, and JEDEC-compliant ±15 mV VTT accuracy - making it optimal for cost- and thermal-constrained DDR266/333 systems where VTT matching across DIMMs is critical.

Availability

NE57814DD,518 is available at Aetrix Electronics and suitable for laptop computers, desktop microcomputer systems, servers, and networking routers and switches requiring stable component supply, long-lifecycle support, and guaranteed thermal performance in DDR memory termination roles.

Supply support for NE57814DD,518 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

NXP Semiconductors (originally Philips Semiconductors) is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and consumer applications.

The NE57814DD,518 belongs to NXP's legacy DDR power management portfolio, engineered specifically for high-efficiency, low-noise termination of DDR SDRAM buses in space- and power-constrained computing platforms.

FAQ

What is the maximum output current capability of the NE57814DD,518?

The NE57814DD,518 supports ±3.5 A output current when VD = VDD = 2.5 V to 3.6 V, and ±2.5 A when VD = VDD = 1.6 V. This is verified per the Electrical Characteristics table (page 4), where ITT is specified across those conditions. The device includes over-current protection with a 4.5 A typical current limit to prevent damage during bus contention events. Peak sourcing capability depends on VD headroom - e.g., at VD = VTT + 0.25 V, full ±3.5 A is maintained.

How does the VD pin improve efficiency in the NE57814DD,518?

The VD pin allows the NE57814DD,518 to source VTT current from a voltage only ~0.25 V above VTT, rather than from VDD. This reduces power dissipation in the pass element: for example, at 3.5 A sourcing, dropping from 2.5 V to 1.25 V (VDD-only) wastes 4.375 W, whereas dropping from 1.5 V to 1.25 V (VD-optimized) wastes only 0.875 W - yielding up to 65% efficiency gain. This is documented in the High Efficiency Operating Mode section (page 9) and confirmed by the efficiency equations provided.

Can multiple NE57814DD,518 devices be connected in parallel for higher current?

No - the NE57814DD,518 output stage is not designed for parallel operation. Its VTT output is a low-impedance voltage source, and connecting outputs together would cause devices to "fight" due to millivolt-level VTT mismatches, risking instability or damage. Instead, the datasheet explicitly recommends cascading via RefOut→ExtRefIn for multi-DIMM systems (page 11), which maintains tight VTT matching (<12 mV) without paralleling outputs.

What is the purpose of the VTT SENSE pin on the NE57814DD,518?

The VTT SENSE pin (Pin 2) provides remote sensing of the actual VTT voltage at the DDR bus termination point, compensating for IR drop across PCB traces between the NE57814DD,518 output and the DIMM. It must be connected directly to Pin 3 (VTT) per the Pin Description (page 3) and Figure 1. This closed-loop feedback ensures VTT regulation accuracy remains within ±15 mV at the load, not just at the IC pin - critical for meeting DDR signal integrity specifications.

Does the NE57814DD,518 support DDR2 or DDR3 memory standards?

The NE57814DD,518 was designed and characterized for DDR SDRAM (DDR1) systems operating at 200–333 MHz, as confirmed by its 2003 datasheet release, application examples (laptops, desktops, servers), and electrical specs (e.g., ±3.5 A peak current matches DDR266/333 bus loading models). It does not meet DDR2/DDR3 timing, voltage (1.8 V/1.5 V), or feature requirements (e.g., ODT control), and no documentation supports DDR2/DDR3 compatibility.