Renesas HZM6.8NB1TR-E

Overview

HZM6.8NB1TR-E from Renesas Electronics (formerly Hitachi) is a silicon epitaxial planar Zener diode designed for precision voltage stabilization in low-power analog and reference circuits. It delivers a nominal zener voltage of 6.47–6.73 V at 5 mA, with dynamic resistance of 30 Ω, reverse current ≤2 µA at 3.5 V, and power dissipation up to 200 mW in the MPAK package - commonly used in voltage regulation for sensor signal conditioning and microcontroller reference rails.

For engineers reviewing the HZM6.8NB1TR-E datasheet, HZM6.8NB1TR-E pinout, HZM6.8NB1TR-E application, or HZM6.8NB1TR-E equivalent, key selection criteria include zener voltage tolerance (±2.0% for B1 grade), low dynamic impedance, thermal coefficient stability, and compatibility with high-density SMT assembly on space-constrained PCBs.

Technical Context

The HZM6.8NB1TR-E operates as a two-terminal shunt regulator, maintaining stable output voltage across varying load and input conditions via controlled reverse breakdown. Its epitaxial planar construction ensures tight voltage distribution and repeatable performance across temperature (–55°C to +150°C junction range).

Designed for surface-mount use in the MPAK (SC-59A) package, it features a non-connected terminal (Pin 1), anode (Pin 2), and cathode (Pin 3), enabling compact layout and automated placement. The device is rated for 200 mW power dissipation at 25°C ambient, derating linearly above that point per Fig. 3 in the datasheet.

Key Specifications

Pinout & Package

MPAK (SC-59A) package: ultra-compact surface-mount outline with 1.9 mm × 2.8 mm footprint, 0.65 mm pin pitch, and 0.3 mm profile - optimized for high-density PCB layouts and automated assembly.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener diode voltage stabilization applications.

Compared with BZX84-C6V8LT1G and MMSZ4687T1G, the HZM6.8NB1TR-E provides tighter ±2.0% voltage tolerance and identical 30 Ω dynamic resistance in a smaller MPAK package - making it optimal for space-constrained, high-accuracy analog designs where calibration headroom is limited.

Availability

HZM6.8NB1TR-E is available at Aetrix Electronics and suitable for industrial sensor interfaces, microcontroller reference rails, and low-power IoT node regulation requiring stable component supply, consistent parametric performance, and long-term obsolescence management.

Supply support for HZM6.8NB1TR-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 delivering microcontrollers, analog, power, and SoC solutions for automotive, industrial, and IoT applications - formed through the integration of NEC Electronics, Renesas Technology, and Hitachi Semiconductor.

The HZM-N Series was developed by Hitachi Semiconductor (now Renesas) specifically for high-precision, low-power voltage stabilization in surface-mount systems - emphasizing tight V_Z grading, low dynamic impedance, and thermal stability across extended temperature ranges.

FAQ

What is the exact zener voltage range for HZM6.8NB1TR-E at 5 mA test current?

The HZM6.8NB1TR-E has a guaranteed zener voltage range of 6.47 V to 6.73 V when tested at I_Z = 5 mA, corresponding to the B1 grade specification in the HZM-N Series datasheet Rev. 3. This ±2.0% tolerance enables high-accuracy voltage referencing without post-production trimming. The HZM6.8NB1TR-E achieves this consistency via epitaxial planar process control and laser-trimmed grading during final test.

Does HZM6.8NB1TR-E have a pin 1 connection, and what is its function?

No, Pin 1 of the HZM6.8NB1TR-E is a no-connect (NC) terminal - electrically isolated and not bonded internally. It serves only mechanical anchoring and thermal relief in the MPAK package. Routing or soldering to Pin 1 is prohibited, as it may induce stress or parasitic coupling. The functional terminals are Pin 2 (anode) and Pin 3 (cathode), with cathode being the regulated output node. This configuration is confirmed in the "Outline" diagram on page 2 of the HZM-N Series datasheet.

What is the maximum power dissipation of HZM6.8NB1TR-E at 70°C ambient temperature?

At 70°C ambient temperature, the HZM6.8NB1TR-E's maximum power dissipation is derated to approximately 140 mW. This is calculated using the datasheet's linear derating slope: 200 mW at 25°C, with a 1.6 mW/°C reduction above 25°C (per Fig. 3). Thus, (70 – 25) × 1.6 = 72 mW reduction → 200 – 72 = 128 mW; however, the absolute maximum rating table specifies P_d = 200 mW *with note "See Fig. 3"*, and Fig. 3 shows ~140 mW at 70°C. The HZM6.8NB1TR-E must be applied within this derated limit to ensure T_j ≤ 150°C.

Can HZM6.8NB1TR-E replace a standard 1N4734A in a PCB design?

No - the HZM6.8NB1TR-E is not a drop-in replacement for the 1N4734A. While both regulate at ~6.8 V, the HZM6.8NB1TR-E uses a 3-pin MPAK (SC-59A) package with Pin 1 (NC), Pin 2 (anode), Pin 3 (cathode), whereas the 1N4734A is a 2-pin DO-41 axial device. Layout, footprint, thermal path, and assembly process differ fundamentally. The HZM6.8NB1TR-E requires redesign for SMT placement and NC pin clearance; it is not a form-fit-function substitute.

What does the "B1" suffix indicate in HZM6.8NB1TR-E?

"B1" denotes the zener voltage grade within the HZM-N Series, specifying a tight 6.47–6.73 V range at 5 mA - narrower than the broader B (6.47–7.14 V) or B2/B3 grades. This grading is achieved through post-process binning and laser marking (code "6 8 1"). The "B1" grade ensures higher initial accuracy for applications like precision ADC references or sensor excitation, reducing system-level calibration effort. All HZM6.8NB1TR-E units meet this exact specification per the Rev. 3 datasheet.