NXP Semiconductors 1N4448,143

Overview

1N4448,143 from Nexperia is a high-speed switching diode in a hermetically sealed glass SOD27 (DO-35) package, rated for 100 V repetitive peak reverse voltage, 450 mA repetitive peak forward current, and 4 ns maximum reverse recovery time. It serves as a fast signal-level clamp or logic-level switching element in digital timing circuits, pulse shaping networks, and protection paths.

For engineers reviewing the 1N4448,143 datasheet, 1N4448,143 pinout, 1N4448,143 application, or 1N4448,143 equivalent, key selection criteria include its low 0.62–0.72 V forward voltage at 5 mA, sub-4 pF capacitance at 0 V, 3 µA max reverse leakage at 100 °C, and compatibility with high-frequency (>10 MHz) small-signal switching where thermal robustness to 200 °C junction temperature is required.

Technical Context

The 1N4448,143 employs planar silicon technology optimized for rapid carrier recombination, enabling nanosecond-scale reverse recovery. Its electrical behavior is characterized by tightly controlled VF (0.62–0.72 V @ 5 mA), low Cd (<4 pF @ 1 MHz, VR = 0 V), and stable IR (<3 µA @ VR = 20 V, Tj = 100 °C).

Designed for discrete signal routing-not power rectification-it operates within a 25–200 °C junction range and delivers consistent trr ≤ 4 ns under standardized IF = 10 mA → IR = 60 mA switching conditions with RL = 100 Ω load and IR = 1 mA measurement threshold.

Key Specifications

Pinout & Package

Package: Hermetically sealed axial-leaded glass SOD27 (DO-35); cathode indicated by black band on body; lead spacing 25.4 mm; body diameter 1.85 mm; length 4.25 mm.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar high-speed switching diode applications.

Compared with 1N4448,143, the 1N4148,113 trades lower forward voltage for slightly higher conduction loss, while the BAS16,215 offers superior RF performance and footprint reduction at the expense of through-hole compatibility and thermal mass.

Availability

1N4448,143 is available at Aetrix Electronics and suitable for high-speed signal routing, logic-level clamping, and RF detector biasing requiring stable component supply across automotive, industrial control, and test equipment programs.

Supply support for 1N4448,143 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

Nexperia is a global leader in discrete, logic, and PowerMOS semiconductors, formed in 2017 from the former NXP Standard Products division.

The 1N4448,143 belongs to Nexperia's high-speed diode product line, engineered specifically for nanosecond-scale signal integrity preservation in digital, RF, and precision analog subsystems.

FAQ

What is the maximum reverse recovery time specified for the 1N4448,143?

The 1N4448,143 has a maximum reverse recovery time (t_rr) of 4 ns when switched from I_F = 10 mA to I_R = 60 mA with R_L = 100 Ω and measured at I_R = 1 mA. This value is guaranteed across the full operating temperature range and defines its suitability for >100 MHz edge-sensitive applications. The 1N4448,143 achieves this performance via optimized planar junction design and low-carrier-lifetime silicon processing.

Does the 1N4448,143 have a specified forward voltage at 100 mA?

Yes-the 1N4448,143 has a maximum forward voltage of 1.0 V at I_F = 100 mA and T_j = 25 °C. This parameter appears in the Electrical Characteristics table and reflects conduction behavior under moderate-current switching loads. While the diode is typically used at lower currents (e.g., 5 mA for logic clamping), the 1.0 V rating confirms headroom for brief surge conditions without thermal runaway. The 1N4448,143 maintains this specification across its qualified temperature range.

Is the 1N4448,143 compatible with lead-free reflow soldering processes?

Yes-the 1N4448,143's SOD27 (DO-35) glass package is rated for standard lead-free reflow profiles, including peak temperatures up to 260 °C for 10 seconds. Nexperia qualifies this part for JEDEC J-STD-020 moisture sensitivity level 1 (MSL-1), meaning it may be stored indefinitely at ≤30 °C/85% RH without baking. The 1N4448,143's hermetic seal prevents internal moisture ingress, eliminating popcorning risk during reflow.

What is the cathode identification method on the 1N4448,143 package?

The cathode of the 1N4448,143 is marked by a distinct black band on the glass body, positioned adjacent to the cathode lead. This marking complies with IEC 60747-2 and is visible under standard AOI systems. The anode is the unmarked lead. The 1N4448,143 uses this industry-standard polarity indicator to prevent reverse installation during manual or automated placement-critical for maintaining reverse-blocking functionality in signal-path protection circuits.

Can the 1N4448,143 replace the 1N4148 in existing designs?

The 1N4448,143 can replace the 1N4148 in most applications but with important distinctions: its lower forward voltage (0.62–0.72 V @ 5 mA vs. ≤1.0 V for 1N4148) improves efficiency in low-current logic interfaces, while identical t_rr, V_RRM, and package ensure mechanical and dynamic compatibility. However, the 1N4448,143's tighter VF spec may affect bias point stability in some analog circuits. Reviewing the specific 1N4448,143 datasheet is recommended before substitution.