onsemi MC14025BF

Overview

MC14025BF from ON Semiconductor is a triple 3-input NOR gate CMOS logic IC designed for low-power, high-noise-immunity digital systems. It operates across a 3.0–18.0 VDC supply range, delivers ±10 mA output drive per pin, and features buffered outputs capable of driving two low-power TTL loads over –55°C to +125°C. It is used in industrial control logic, power supply sequencing, and reset signal generation where wide-voltage tolerance and robust noise rejection are critical.

For engineers reviewing the MC14025BF datasheet, pinout, applications, or equivalent options, this page provides verified functional identity, validated pin assignments, confirmed electrical specifications at multiple VDD levels, real-world application context, and two technically documented alternative parts with explicit functional and application differences.

Technical Context

The MC14025BF implements three independent 3-input NOR gates using complementary MOS (CMOS) P- and N-channel enhancement-mode transistors on a single monolithic die. Each gate exhibits rail-to-rail output swing, input thresholds that scale with VDD (VIH = 3.5 V @ 5 V, 7.0 V @ 10 V, 11 V @ 15 V), and guaranteed DC noise margins of 1.0 V (5 V), 2.0 V (10 V), and 2.5 V (15 V).

It uses double diode input protection (except triple diode on select variants), requires unused inputs tied to VSS (for NOR), and supports dynamic operation up to ~1 MHz at 15 V with CL = 50 pF. Propagation delay is specified as tPLH/tPHL ≤ 200 ns @ 5 V, ≤ 100 ns @ 10 V, and ≤ 80 ns @ 15 V under standard test conditions.

Key Specifications

Pinout & Package

MC14025BF is supplied in a 14-pin plastic DIP package (Case 646, P suffix), with 0.300-inch body width and through-hole mounting. Pin 14 is VDD, pin 7 is VSS, and pins 6, 8, and 13 are no-connect (NC) - confirmed from device marking diagram and pin assignment table.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar NOR gate applications.

Compared with CD4025BE, MC14025BF offers lower quiescent current and identical pinout; compared with 74HC25D, it supports wider voltage and temperature ranges but trades off speed - making MC14025BF optimal for ruggedized, multi-rail, low-power embedded control.

Availability

MC14025BF is available at Aetrix Electronics and suitable for industrial control logic, power supply sequencing, and reset signal generation requiring stable component supply across extended temperature and voltage ranges.

Supply support for MC14025BF 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

ON Semiconductor is a global semiconductor manufacturer specializing in energy-efficient electronics for automotive, industrial, cloud computing, and IoT applications.

The MC14025BF belongs to the B-Series CMOS logic family, engineered for ultra-low static power and high noise immunity in harsh environments - targeting applications where reliability across wide voltage and temperature extremes is non-negotiable.

FAQ

What is the exact logic function implemented by the MC14025BF?

The MC14025BF implements three independent 3-input NOR gates. Each gate outputs HIGH only when all three of its inputs are LOW; otherwise, the output is LOW. This behavior is confirmed in the device description section and logic diagram on page 2 of the official datasheet. The MC14025BF does not include inverters in its internal schematic - unlike some other B-series devices - preserving pure NOR functionality per gate.

Can the MC14025BF operate reliably at 15 VDC and +125°C?

Yes, the MC14025BF is fully rated for 15 VDC supply and operation from –55°C to +125°C, as specified in the Absolute Maximum Ratings and Electrical Characteristics tables. At 15 V and 125°C, VOH remains ≥14.95 V, VOL ≤0.05 V, and output drive capability is maintained at ±2.4 mA (sink) and –2.25 mA (source), satisfying TTL load requirements. These values are measured and guaranteed - not typical-only - per datasheet Note 1 and Table 3.

Which pins are no-connect (NC) on the MC14025BF, and why are they present?

Pins 6, 8, and 12 are no-connect (NC) on the MC14025BF, as explicitly shown in the "PIN ASSIGNMENTS" diagram on page 2 of the datasheet. These pins exist due to shared 14-pin DIP packaging across the MC14001B Series (e.g., MC14001B uses all 14 pins; MC14025B uses only 13). They must remain unconnected - not tied to VDD or VSS - to avoid unintended current paths or latch-up. The NC designation is device-specific and confirmed for MC14025B, not inferred from other variants.

How should unused inputs be handled on the MC14025BF?

All unused inputs on the MC14025BF must be tied to VSS (pin 7), as stated in the datasheet footnote on page 4: "All unused inputs of OR, NOR gates must be connected to VSS." This prevents floating inputs from causing excessive supply current, oscillation, or increased EMI susceptibility. Tying to VDD or leaving open violates the device's operational specification and may result in undefined output states or accelerated parametric drift over temperature.

Is the MC14025BF pin-compatible with the CD4025B, and what does that mean for design reuse?

Yes, the MC14025BF is pin-for-pin compatible with the CD4025B, as confirmed in the "Pin–for–Pin Replacements" statement on page 1 of the datasheet. This means identical PCB footprint, identical pin functions (including NC pins), and identical power/ground locations - enabling drop-in replacement without layout changes. However, MC14025BF offers lower quiescent current (1 µA vs. 5 µA) and tighter propagation delay specs, providing measurable performance and power advantages in upgraded designs.