Renesas HZC4.3TRF-E

Overview

HZC4.3TRF-E from Renesas Electronics is a silicon epitaxial planar Zener diode optimized for surge absorption in low-power signal-line protection circuits, featuring a nominal Zener voltage of 4.3 V (4.01–4.48 V), 150 mW power dissipation, and ultra-small UFP (SC-79) surface-mount package. It delivers 130 Ω dynamic resistance at 5 mA test current and supports ±30 kV ESD capability per IEC 61000-4-2 (C = 150 pF, R = 330 Ω).

For engineers reviewing the HZC4.3TRF-E datasheet, HZC4.3TRF-E pinout, HZC4.3TRF-E application, or HZC4.3TRF-E equivalent, key selection considerations include its precise 4.3 V clamping threshold, low thermal coefficient (−0.02 %/°C typical), SC-79 footprint compatibility, and suitability for USB, audio I/O, and sensor interface transient suppression where space-constrained, low-leakage protection is required.

Technical Context

The HZC4.3TRF-E operates as a two-terminal voltage-reference clamp, leveraging epitaxial planar junction technology to achieve stable reverse breakdown with minimal leakage (<10 µA at 1.0 V). Its design targets fast transient response in low-energy surge events, not continuous regulation.

It is rated for 150 mW maximum power dissipation at 25°C ambient, derating linearly above 25°C per Fig.2, and supports junction temperatures up to 150°C. The device exhibits a negative temperature coefficient of −0.02 %/°C (≈ −0.86 mV/°C) near 4.3 V, confirmed in Fig.2 of the official datasheet.

Key Specifications

Pinout & Package

Package: Ultra Small Flat Lead (UFP), JEITA code SC-79, Renesas code PWSF0002ZA-A, mass 0.0016 g. Dimensions: 1.70 × 1.20 × 0.60 mm (L × W × H), with cathode marked by laser dot.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener diode surge absorption applications.

Compared with MMBZ4685T1G and BZX584-C4V3, the HZC4.3TRF-E offers identical clamping voltage and ESD rating in the smallest available footprint (SC-79), making it optimal for ultra-dense layouts where thermal stress is managed via system-level derating-not device-level power headroom.

Availability

HZC4.3TRF-E is available at Aetrix Electronics and suitable for USB interface protection, audio I/O hardening, and sensor signal-line surge suppression requiring stable component supply, consistent tape-and-reel packaging, and RoHS-compliant manufacturing.

Supply support for HZC4.3TRF-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 global semiconductor leader specializing in microcontrollers, analog, power, and mixed-signal solutions for automotive, industrial, and IoT applications.

The HZC Series belongs to Renesas' discrete protection portfolio, designed specifically for compact, high-reliability surge absorption in space-constrained consumer and industrial electronics-emphasizing low leakage, tight voltage tolerance, and SC-79 mountability.

FAQ

What is the exact Zener voltage tolerance for HZC4.3TRF-E?

The HZC4.3TRF-E has a guaranteed Zener voltage range of 4.01 V to 4.48 V at 5 mA test current, as specified in the official Renesas datasheet REJ03G1204-0200 Rev.2.00. This ±5.5% tolerance ensures reliable clamping on 3.3 V and 5 V logic rails without undershoot or overshoot beyond system safety margins. The HZC4.3TRF-E's tight binning supports consistent performance across production lots.

Does HZC4.3TRF-E support bidirectional ESD protection?

No-HZC4.3TRF-E is a unidirectional Zener diode configured for reverse-bias clamping only. It protects the cathode-connected line against positive transients relative to anode (ground). For true bidirectional protection, two HZC4.3TRF-E devices must be used in series opposition or a dedicated TVS array selected. The HZC4.3TRF-E's ±30 kV ESD rating applies only in the reverse direction per IEC 61000-4-2 test conditions.

What is the thermal derating behavior of HZC4.3TRF-E above 25°C?

HZC4.3TRF-E follows linear thermal derating: power dissipation decreases by 1.2 mW/°C above 25°C ambient, reaching zero at approximately 138°C (per Fig.2 in REJ03G1204-0200). At 85°C ambient, its usable P_d drops to ~78 mW. Designers must verify junction temperature using θ_JA ≈ 833°C/W (calculated from 150 mW / (138°C − 25°C)) and ensure board copper area supports this thermal resistance for the HZC4.3TRF-E.

Is HZC4.3TRF-E compatible with lead-free reflow soldering?

Yes-HZC4.3TRF-E is qualified for lead-free reflow per J-STD-020, with peak reflow temperature up to 260°C (10-second duration). Its UFP package uses matte tin plating and meets RoHS Directive 2011/65/EU requirements. The HZC4.3TRF-E's polyimide-substrate-compatible construction ensures no delamination or voiding during standard Pb-free profile ramp rates (≤3°C/s).

How does the temperature coefficient affect HZC4.3TRF-E's clamping voltage in real-world operation?

The HZC4.3TRF-E exhibits a negative temperature coefficient of −0.02 %/°C (≈ −0.86 mV/°C), meaning its Zener voltage decreases by ~0.86 mV per °C rise. Over a −25°C to +85°C range, clamping shifts by ±95 mV-well within its 4.01–4.48 V spec band. This predictable drift allows designers to maintain margin for worst-case clamping in HZC4.3TRF-E-based protection schemes without recalibration.