Renesas 74HC148FPEL-E

Overview

74HC148FPEL-E from Renesas Electronics is an 8-to-3-line octal priority encoder IC in SOP-16 package, operating from 2 V to 6 V supply, with 15 ns typical propagation delay (CL = 50 pF), active-low inputs/outputs, and cascading enable input (EI) and enable output (EO) for multi-stage encoding in industrial control panels and keyboard scan circuits.

For engineers reviewing the 74HC148FPEL-E datasheet, 74HC148FPEL-E pinout, 74HC148FPEL-E application, or 74HC148FPEL-E equivalent, this device supports low-voltage logic interfacing, priority resolution of up to eight interrupt sources, and direct integration into HC-family bus systems without level-shifting.

Technical Context

The 74HC148FPEL-E implements a fixed-function priority encoding logic where input line 7 has highest priority and line 0 lowest; all inputs and outputs are active-low, requiring external pull-ups for open-drain compatibility. Encoding follows standard 4-2-1 binary weighting (A2–A0), with GS (Group Select) and EO (Enable Output) supporting daisy-chained expansion across multiple encoders.

It uses silicon-gate CMOS technology for rail-to-rail input voltage tolerance (–0.5 V to VCC + 0.5 V), static ICC ≤ 4 µA at 25°C, and guaranteed operation from –40°C to +85°C - meeting Standard-grade reliability per Renesas quality classification for industrial and office equipment applications.

Key Specifications

Pinout & Package

SOP-16 (JEITA PRSP0016DH-B / FP-16DAV), 10.06 mm × 5.5 mm body, 1.27 mm pitch, Ni/Pd/Au plating, tape-and-reel packaging (2,000 pcs/reel).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar priority encoder applications.

Compared with SN74HC148N and CD74HC148E, the 74HC148FPEL-E delivers identical core functionality in JEITA-standard SOP-16 packaging optimized for automated assembly, while maintaining full compatibility with industry-standard 74HC148 logic behavior and timing.

Availability

74HC148FPEL-E is available at Aetrix Electronics and suitable for industrial control panels, keyboard scan interfaces, and interrupt arbitration circuits requiring stable component supply, long-term manufacturability, and RoHS-compliant packaging.

Supply support for 74HC148FPEL-E 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 Japanese semiconductor manufacturer specializing in microcontrollers, analog, and logic devices for industrial, automotive, and infrastructure markets.

The HD74HC148 product line delivers standardized 74HC-series logic functions with industrial-grade qualification, designed specifically for reliable operation in office equipment, test instruments, and factory automation systems.

FAQ

What is the function of the GS pin on the 74HC148FPEL-E?

The GS (Group Select) pin on the 74HC148FPEL-E is an active-low output that goes low whenever any of the eight data inputs (0–7) is asserted (low). It serves as a validity flag indicating that a valid encoded output is present on A2–A0. When all inputs are high (inactive), GS remains high - allowing downstream logic to detect idle state. This signal is essential for synchronizing read operations in microcontroller interfaces.

Does the 74HC148FPEL-E support cascading with other priority encoders?

Yes, the 74HC148FPEL-E supports hardware cascading via its EI (Enable Input) and EO (Enable Output) pins. When multiple 74HC148FPEL-E devices are chained, the EO of a higher-priority stage connects to the EI of the next stage. This allows expansion to 16-, 24-, or more input lines while preserving priority hierarchy - no external logic required. The EO pin goes low only when EI is low and all local inputs are high.

What is the maximum propagation delay of the 74HC148FPEL-E at 5 V supply?

At VCC = 4.5 V, the 74HC148FPEL-E exhibits a maximum propagation delay of 58 ns (tPLH/tPHL) from any data input (0–7) to the A0–A2 outputs under CL = 50 pF load conditions. This value is specified over the full operating temperature range (–40°C to +85°C). At 25°C, the typical delay is 15 ns - enabling sub-60 ns deterministic response critical for real-time interrupt handling.

Is the 74HC148FPEL-E compatible with 3.3 V microcontroller I/O?

Yes, the 74HC148FPEL-E is fully compatible with 3.3 V microcontroller I/O. Its VCC range spans 2 V to 6 V, and its input thresholds (VIH = 2.1 V min, VIL = 1.35 V max at VCC = 3.3 V) ensure robust recognition of 3.3 V logic levels. Outputs swing rail-to-rail, delivering >3.1 V VOH and <0.26 V VOL at 4 mA load - meeting 3.3 V CMOS input requirements without level shifters.

What package type does the 74HC148FPEL-E use, and is it RoHS-compliant?

The 74HC148FPEL-E uses a SOP-16 package (JEITA PRSP0016DH-B, Renesas code FP-16DAV), measuring 10.06 mm × 5.5 mm with 1.27 mm lead pitch. It features Ni/Pd/Au plating and is supplied in tape-and-reel format (2,000 pcs/reel). Per Renesas documentation and EU RoHS Directive compliance statements, the 74HC148FPEL-E is RoHS-compliant and contains no restricted substances above threshold limits.