NXP Semiconductors N74F138D,602

Overview

N74F138D,602 from NXP Semiconductors (formerly Philips) is a 1-of-8 decoder/demultiplexer IC with active-low outputs, three binary address inputs (A0–A2), and three enable inputs (E0, E1 low-active; E2 high-active). It delivers 5.8 ns typical propagation delay, 13 mA typical supply current, and operates across industrial temperature range (–40°C to +85°C) at VCC = 5V ±10%. It is used for memory chip select decoding in embedded control systems.

For engineers reviewing the N74F138D,602 datasheet, N74F138D,602 pinout, N74F138D,602 application, or N74F138D,602 equivalent, key selection criteria include enable input logic polarity, output drive capability (20 mA sink), fan-out loading (50/33 U.L.), propagation delay symmetry across address vs. enable paths, and SO16 package compatibility with surface-mount production.

Technical Context

The N74F138D,602 implements a fully decoded 3-to-8 logic function with mutually exclusive active-low outputs. Its triple-enable architecture (two low-active, one high-active) enables cascading up to 1-of-32 decoding using four devices and one inverter - no external logic beyond inversion is required for expansion.

It functions as an 8-output demultiplexer when one active-low enable (e.g., E0) serves as data input and the remaining enables act as strobes. All outputs remain high unless E0 = L, E1 = L, and E2 = H - this strict enable condition prevents spurious decoding during power-up or bus contention.

Key Specifications

Pinout & Package

Package: 16-pin plastic small outline (SO16), SOT109-1 footprint, 1.27 mm pitch, 3.9 mm body width, gull-wing lead form.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 1-of-8 decoder/demultiplexer applications.

Compared with SN74F138N and 74ACT138SCX, the N74F138D,602 offers SO16 surface-mount compatibility and guaranteed industrial temperature operation - critical for automated production and harsh-environment deployments where DIP sockets or CMOS input thresholds introduce risk.

Availability

N74F138D,602 is available at Aetrix Electronics and suitable for memory decoding, address demultiplexing, LED array control, and priority interrupt encoding requiring stable component supply and long-term industrial-grade availability.

Supply support for N74F138D,602 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, delivering high-performance analog, logic, and interface solutions for automotive, industrial, and communication markets.

The 74F logic family - including the N74F138D,602 - was designed for high-speed, low-power 5 V TTL-compatible digital systems requiring robust timing margins and industrial reliability.

FAQ

What is the maximum clock frequency supported by the N74F138D,602?

The N74F138D,602 is a combinational logic device without a clock input. Its maximum usable switching rate is determined by propagation delay: with 5.8 ns typical tPD, it supports reliable operation in systems with address/data setup times ≥8 ns. For 50 MHz bus systems, it meets timing when paired with appropriate latch enable sequencing. The N74F138D,602 does not specify a clock frequency but guarantees functional correctness up to its AC limits.

Can the N74F138D,602 be used as a demultiplexer, and how is that configured?

Yes, the N74F138D,602 can operate as an 8-output demultiplexer. Configure one active-low enable input (e.g., E0) as the data input, tie E1 low and E2 high to permanently enable, then use A0–A2 as the 3-bit channel select. When E0 is low, the selected output goes low; when E0 is high, all outputs remain high. This configuration is explicitly validated in the Philips datasheet Figure 1 and Function Table. The N74F138D,602 requires no additional components for basic DMUX operation.

What are the absolute maximum ratings for VCC and input voltage on the N74F138D,602?

The N74F138D,602 has an absolute maximum VCC rating of –0.5 V to +7.0 V and absolute maximum input voltage (VIN) of –0.5 V to +7.0 V. Exceeding these values may cause permanent damage. Recommended operating VCC is 4.5 V to 5.5 V. Input clamp voltage is specified at –1.2 V (min), confirming robustness against negative transients. These ratings are defined in the Philips datasheet Section "Absolute Maximum Ratings" and apply to the N74F138D,602 in SO16 package.

Is the N74F138D,602 pin-compatible with the SN74F138N?

No, the N74F138D,602 and SN74F138N share identical pin functions but differ in package: N74F138D,602 uses SO16 (SOT109-1), while SN74F138N uses DIP16 (SOT38-4). Pin numbering and signal mapping match exactly (e.g., Pin 1 = E0, Pin 16 = VCC), but physical layout, solder footprint, and thermal characteristics differ. The N74F138D,602 is not a drop-in replacement without PCB redesign - it requires SO16 land pattern and reflow process.

Does the N74F138D,602 support operation at 3.3 V supply?

No, the N74F138D,602 is specified only for 5 V ±10% operation (4.5 V to 5.5 V). Its input thresholds (VIH = 2.0 V min, VIL = 0.8 V max) and output drive (VOH ≥ 2.7 V at IOH = –1 mA) are optimized for 5 V TTL compatibility. At 3.3 V, it fails to meet VIH specification and risks incorrect logic interpretation. For 3.3 V systems, consider 74ACT138 or 74LVC138 instead. This limitation applies strictly to the N74F138D,602.