Nexperia USA Inc. PDZ3.9B-QF

Overview

PDZ3.9B-QF from Nexperia is a single Zener diode in SOD323 (SC-76) package, designed for low-power voltage regulation at nominal 3.9 V with ±2 % tolerance, 500 Ω dynamic impedance at 1 mA, and 3 μA reverse leakage at 1 V. It delivers stable reference voltage in automotive power supply rails, ECU bias networks, and sensor interface protection circuits.

For engineers reviewing the PDZ3.9B-QF datasheet, PDZ3.9B-QF pinout, PDZ3.9B-QF application, or PDZ3.9B-QF equivalent, this device supports AEC-Q101-compliant designs requiring precise low-current Zener regulation, thermal stability up to +150 °C junction temperature, and surface-mount compatibility on FR4 PCBs with standard reflow footprints.

Technical Context

This Zener diode operates in reverse breakdown mode with a nominal working voltage of 3.89 V to 4.16 V at I_Z = 5 mA, exhibiting a negative temperature coefficient of −2.5 mV/K - enabling predictable drift compensation in analog reference chains. Its hard breakdown knee ensures sharp regulation onset below 100 μA current.

Thermal resistance from junction to solder point is 130 K/W in free air, and total power dissipation is rated at 400 mW at T_amb ≤ 25 °C on standard FR4 PCB. Forward voltage remains ≤ 0.9 V at 10 mA, supporting dual-use as clamp and regulator in bidirectional protection schemes.

Key Specifications

Pinout & Package

SOD323 (SC-76) surface-mount plastic package with 2 leads; cathode marked by bar on top surface; body dimensions: 1.35 mm × 1.75 mm × 0.95 mm height; recommended reflow solder land pattern per Figure 9 (0.6 mm × 0.5 mm pads, 0.95 mm center-to-center).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener regulation applications.

Compared with BZX384-B3V9 and MMSZ4685, PDZ3.9B-QF provides tighter tolerance, lower leakage, full AEC-Q101 qualification, and guaranteed +150 °C operation - making it the sole choice for automotive power management and high-reliability sensor biasing.

Availability

PDZ3.9B-QF is available at Aetrix Electronics and suitable for automotive ECU design, industrial sensor calibration, and IoT battery monitoring systems requiring stable component supply with traceable sourcing and lifecycle continuity.

Supply support for PDZ3.9B-QF 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 semiconductor expert focused on essential efficiency technologies, delivering high-performance logic, discrete, and MOSFET devices with emphasis on automotive and industrial reliability.

PDZ3.9B-QF belongs to the PDZ-B-Q series of AEC-Q101-qualified Zener diodes engineered specifically for precision voltage regulation in harsh-environment automotive subsystems and high-stability industrial instrumentation.

FAQ

What is the maximum continuous reverse current the PDZ3.9B-QF can handle without degradation?

The PDZ3.9B-QF is rated for non-repetitive peak reverse current (I_ZSM) of 8.0 A at t_p = 100 μs, but its continuous Zener current is limited by thermal dissipation. At 25 °C ambient on standard FR4, sustained I_Z must remain ≤ 102 mA to stay within 400 mW P_tot, assuming V_Z ≈ 4.0 V. Derating applies above 25 °C per Fig. 1's power curve.

How does the −2.5 mV/K temperature coefficient affect long-term voltage reference stability?

The negative temperature coefficient means V_Z decreases by 2.5 mV per Kelvin rise in junction temperature. At 125 °C junction (100 K above 25 °C), V_Z shifts down ~250 mV - from 4.0 V to ~3.75 V. This predictable drift enables compensation in multi-Zener or resistor-network references, unlike uncharacterized or zero-tempco alternatives.

Can PDZ3.9B-QF be used in forward-bias applications such as LED current limiting?

Yes - its forward voltage is ≤ 0.9 V at 10 mA and ≤ 1.1 V at 100 mA, making it usable as a low-drop series element. However, its 200 mA absolute maximum continuous forward current and lack of forward SOA characterization mean it should only be used in low-power indicator or bias applications, not primary current regulation.

Is the SOD323 package compatible with standard automated optical inspection (AOI) systems?

Yes - the SOD323 package features a visible cathode bar marking and consistent 1.35 mm × 1.75 mm body geometry, fully supported by industry-standard AOI algorithms for polarity verification and solder joint integrity. The 0.95 mm height also avoids shadowing issues common with taller packages during top-down inspection.