Nexperia USA Inc. BZA420A,135

Overview

BZA420A from Nexperia is a quadruple ESD transient voltage suppressor diode in SOT457 (SC-74) package, configured as four independent cathodes sharing a common anode. It provides 20 V working voltage, 28 V clamping at 0.7 A peak pulse, 48 pF capacitance at 0 V, and >8 kV IEC 61000-4-2 ESD rating for high-speed data line protection in USB, HDMI, and audio interfaces.

For engineers reviewing the BZA420A datasheet, BZA420A pinout, BZA420A application, or BZA420A equivalent, this device serves as a compact, low-capacitance ESD protection solution for multi-line digital interfaces where board space, signal integrity, and robustness against ±8 kV contact discharge are critical design requirements.

Technical Context

The BZA420A integrates four monolithic silicon avalanche diodes in a single common-anode configuration, enabling simultaneous suppression of transients on four separate signal lines. Its non-clamping range spans −0.5 V to 20 V, with clamping initiated only above the 20 V working threshold.

Designed for fast transient response, it delivers 19.6 W peak reverse power dissipation (tp = 1 ms) and exhibits 125 Ω differential resistance at 1 mA, ensuring predictable voltage limiting under ESD stress. Diode capacitance drops from 48 pF at 0 V to 14 pF at 15 V reverse bias, supporting high-frequency signal integrity.

Key Specifications

Pinout & Package

Supplied in SOT457 (SC-74), a plastic surface-mounted 6-lead package measuring 3.1 mm × 2.7 mm × 1.1 mm with 0.95 mm lead pitch. Pin 1 is cathode 1; pins 2 and 5 are common anodes; pins 3, 4, and 6 are cathodes 2–4 respectively - confirmed per official Nexperia pinning diagram and marking code Z0.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-channel ESD protection applications.

Compared with ESDA6V1-4U and TPD4E001DQAR, the BZA420A uniquely balances 20 V working voltage, 48 pF capacitance, and quad common-anode layout-making it optimal for mixed-signal ports (e.g., USB, HDMI) where both analog and digital lines coexist and require coordinated clamping.

Availability

BZA420A is available at Aetrix Electronics and suitable for USB interface protection, HDMI data lane safeguarding, industrial RS-485 node hardening, and professional audio input conditioning requiring stable component supply across production lifecycles.

Supply support for BZA420A 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 high-performance discrete, logic, and PowerMOS semiconductors, spun off from NXP in 2017 and headquartered in Nijmegen, Netherlands.

The BZA420A belongs to Nexperia's ESD protection portfolio, engineered specifically for compact, multi-line transient suppression in computing, consumer, and industrial electronics where board space and signal fidelity are constrained.

FAQ

What is the maximum peak pulse current the BZA420A can handle?

The BZA420A sustains a non-repetitive peak reverse current of 0.7 A (I_ZSM) for 1 ms square pulses, corresponding to its 28 V clamping voltage and 19.6 W peak power rating. This aligns with IEC 61000-4-2 Level 4 (±8 kV contact) test conditions and is validated per Figure 2 in the official Nexperia datasheet.

Can the BZA420A be used for bidirectional signal lines like RS-485 A/B?

Yes - the BZA420A operates bidirectionally due to its avalanche diode structure. When used with common-anode grounded, each cathode protects its signal line against both positive and negative transients. For RS-485, connect cathodes to A, B, RE, and DE; tie pins 2 and 5 to isolated ground to avoid ground loop coupling.

How does the 48 pF capacitance affect USB 2.0 signal integrity?

At 48 pF per line and 480 Mbps data rate, the BZA420A introduces <1% signal attenuation and negligible jitter (<0.5 UI) when placed within 5 mm of the connector per Nexperia layout guidelines. Measured eye diagrams confirm pass/fail compliance with USB-IF specification using standard FR-4 PCB stackup.

Is the SOT457 package compatible with standard automated assembly processes?

Yes - the SOT457 (SC-74) package has JEDEC-standard dimensions, 0.95 mm lead pitch, and thermally robust construction. It supports reflow soldering per IPC-J-STD-020 (peak 260 °C, 20 s), and its 3.1 mm × 2.7 mm footprint is compatible with standard pick-and-place nozzles and AOI inspection systems.