NXP Semiconductors NE1618DS,118

Overview

NE1618DS,118 from NXP Semiconductors (formerly Philips) is a dual-channel SMBus-compatible temperature monitor IC for microprocessor systems, measuring local on-chip temperature with ±2 °C accuracy and remote diode temperature with ±1.5 °C (1 °C resolution) or ±1.0 °C (0.125 °C resolution), operating from 3.0–3.6 V, consuming 80 µA active / 3 µA standby current, in a 16-lead QSOP package.

For engineers reviewing the NE1618DS,118 datasheet, NE1618DS,118 pinout, NE1618DS,118 application, or NE1618DS,118 equivalent, key selection considerations include remote sensor interface compatibility (NPN/PNP diode-connected transistors), programmable SMBus address (9 options via ADD0/ADD1), extended-mode 0.125 °C remote resolution, hardware/software standby control (STBY pin & RUN/STOP bit), and alarm threshold programmability for thermal management in space-constrained embedded platforms.

Technical Context

The NE1618DS,118 implements a sigma-delta A-to-D converter for local sensing and a two-current-source (10 µA / 100 µA) diode V_BE delta measurement architecture for remote sensing. It supports automatic periodic conversion at user-programmable rates (0.06–8 Hz) and immediate one-shot triggering via SMBus command 0Fh.

Its SMBus 2-wire interface uses open-drain SDATA/SCLK with external 10 kΩ pull-ups, complies with SMBus timing (f_SCLK ≤ 100 kHz, t_LOW/t_HIGH ≥ 4.7/4.0 µs), and lacks SMBus timeout capability. Device addressing uses ADD0/ADD1 pins to select one of nine 7-bit slave addresses (e.g., 0011000b to 1001110b).

Key Specifications

Pinout & Package

NE1618DS,118 is housed in a 16-lead QSOP (SOT519-1) package, 3.9 mm × 4.9 mm body, 0.65 mm pitch, with exposed pad not electrically connected. Pin 1 is TEST1 (factory use only); pins 7 and 8 are GND; pin 15 is STBY (hardware standby control); pins 11, 12, and 14 serve ALERT, SDATA, and SCLK respectively for SMBus communication.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar temperature monitor applications.

Compared with LM94022QDCSQ/NOPB and MAX6642AESA+, the NE1618DS,118 uniquely delivers both local and remote sensing with selectable 0.125 °C extended resolution in a compact QSOP, making it optimal for space-constrained, dual-point thermal monitoring where fine-grained remote die tracking is essential.

Availability

NE1618DS,118 is available at Aetrix Electronics and suitable for desktop computers, notebook computers, and smart battery packs requiring stable component supply throughout product lifecycles.

Supply support for NE1618DS,118 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 is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The NE1618DS,118 belongs to NXP's legacy temperature sensor portfolio originally developed by Philips Semiconductors, designed specifically for SMBus-based thermal management in microprocessor-centric systems with strict power and space constraints.

FAQ

What is the remote sensor compatibility for the NE1618DS,118?

The NE1618DS,118 supports diode-connected NPN transistors (e.g., 2N3904) or PNP transistors (e.g., 2N3906) as remote sensors, and is explicitly validated for use with on-die PNP diodes found in Intel Pentium-series microprocessors. The D+ and D– pins require proper polarity (anode to D+, cathode to D–) and operate within 0.25–0.95 V sensing range. Discrete diodes are not recommended due to mismatched current-source characteristics.

How does the NE1618DS,118 enter and exit extended resolution mode?

The NE1618DS,118 automatically enters extended resolution mode (0.125 °C remote) when the conversion rate register value is ≤ 04h (i.e., ≤ 0.7 Hz). It exits to basic mode (1 °C) when the rate is ≥ 05h (≥ 2 Hz). This transition is fully automatic and requires no firmware intervention - the device reads the conversion rate register at each conversion start to determine mode.

Can the NE1618DS,118 generate interrupts for both over-temperature and under-temperature conditions?

Yes, the NE1618DS,118 supports independent programmable high and low temperature thresholds for both local and remote channels. When either measured temperature equals or exceeds its corresponding high limit, or falls to or below its low limit, the ALERT pin asserts low and the relevant flag bit (bit 0–3) in the status register (RS) is set. All four thresholds are writable via dedicated registers (WIHL/WILL/WEHL/WELL).

What is the function of the STBY pin on the NE1618DS,118?

The STBY pin (Pin 15) provides hardware-controlled entry into low-power standby mode: driving STBY LOW disables the A-to-D converter and reduces supply current to ≤10 µA, while retaining register contents and SMBus responsiveness. Driving STBY HIGH restores full operation. Unlike software standby (RUN/STOP bit), hardware standby prevents any conversion - including one-shot - until STBY returns HIGH.

Does the NE1618DS,118 require external components for basic operation?

Yes, the NE1618DS,118 requires a 0.1 µF decoupling capacitor on VDD (Pin 2), 10 kΩ pull-up resistors on SDATA (Pin 12) and SCLK (Pin 14), and optionally a 2200 pF capacitor on the remote sensor lines (D+/D–) in noisy environments. The ALERT (Pin 11) output also requires an external pull-up resistor to generate a valid interrupt signal.