Renesas RD75F-T7

Overview

RD75F-T7 from Renesas Electronics is a 1 W planar-type silicon Zener diode with a nominal zener voltage of 75 V, ±5% tolerance (B grade), dynamic impedance of 90 Ω at 10 mA, and temperature coefficient of +57 mV/°C. It features a DO-41 glass-sealed DHD (Double Heatsink Diode) package and is rated for surge reverse power up to 400 W (10 μs pulse), suitable for precision voltage regulation and transient suppression in industrial power supplies.

For engineers reviewing the RD75F-T7 datasheet, RD75F-T7 pinout, RD75F-T7 application, or RD75F-T7 equivalent, key selection criteria include its 75 V zener voltage stability under 10 mA test current, low leakage (<5 μA at 60 V), thermal resistance characteristics, and compatibility with standard through-hole PCB layouts using JEDEC DO-41 footprint.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable reference voltage across a defined current range (4–10 mA typical). Its planar junction structure ensures consistent voltage tolerance and long-term stability, while the glass-sealed DO-41 package provides mechanical robustness and reliable thermal dissipation via axial leads.

The device exhibits a positive temperature coefficient (+57 mV/°C), indicating increasing zener voltage with rising junction temperature - a critical factor when designing temperature-compensated references or overvoltage clamps in ambient-variable environments.

Key Specifications

Pinout & Package

RD75F-T7 uses a standard JEDEC DO-41 axial-leaded glass package with cathode indicated by a black band. The device has two terminals: anode and cathode - no internal connections or multi-pin configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with RD75F-T7, BZX85C75 offers marginally higher power handling but nearly identical zener voltage, temperature coefficient, and package - making it suitable for direct substitution in most industrial clamping roles, whereas 1N4742A serves entirely different low-voltage applications and requires circuit redesign.

Availability

RD75F-T7 is available at Aetrix Electronics and suitable for industrial power supplies, overvoltage protection circuits, and DC link monitoring systems requiring stable component supply and long-lifecycle support.

Supply support for RD75F-T7 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 Japanese semiconductor manufacturer specializing in microcontrollers, analog and power devices, and system-on-chip solutions for industrial, automotive, and infrastructure markets.

RD75F-T7 belongs to the RD2.0F–RD82F planar Zener diode family, designed specifically for high-reliability voltage regulation and transient suppression in industrial-grade power conversion and control systems.

FAQ

What is the exact zener voltage tolerance for RD75F-T7?

The RD75F-T7 is specified with a B-grade tolerance of 70 V minimum to 79 V maximum at 10 mA test current, corresponding to ±5% around the nominal 75 V rating. This tolerance is verified per the D13936EJ5V0DS datasheet and applies under standard 40 ms test conditions after power-on. The RD75F-T7 maintains this specification across its qualified operating temperature range.

Does RD75F-T7 have a cathode marking, and how is it identified?

Yes, RD75F-T7 features a black cathode band on the glass body, consistent with JEDEC DO-41 polarity marking standards. The banded end is the cathode, and the unmarked end is the anode. This marking is visible under standard visual inspection and aligns with Renesas' packaging specifications in Document No. D13936EJ5V0DS. Correct orientation is essential for proper shunt regulation or clamping function in the RD75F-T7 application.

Can RD75F-T7 be used in surface-mount designs?

No, RD75F-T7 is exclusively offered in the axial-leaded DO-41 through-hole package and is not available in surface-mount variants such as SOD-123 or SMA. Its mechanical construction and thermal design assume lead-to-board conduction paths. For SMT implementations, engineers must select alternative Zener families like the BZX85 series in DO-204AL or consider discrete SMT alternatives - RD75F-T7 itself does not support reflow or hand-soldered SMT assembly.

What is the maximum allowable surge current for RD75F-T7?

RD75F-T7 supports a peak surge reverse power of 400 W for a 10 μs pulse width at T_A = 25°C, as defined in Figure 7 of the D13936EJ5V0DS datasheet. Translating to current, this corresponds to approximately 5.16 A peak (since I = √(P/Z_Z) ≈ √(400/90)). Exceeding this limit risks irreversible junction damage. The RD75F-T7 must be applied within these non-repetitive surge boundaries to ensure reliability.

Is RD75F-T7 compliant with RoHS and halogen-free standards?

Yes, RD75F-T7 complies with the EU RoHS Directive (2011/65/EU) and is halogen-free per Renesas' environmental policy. This compliance is confirmed in Renesas' official product change notifications and material declarations referenced in Document No. D13936EJ5V0DS. As a "Standard" quality grade device, RD75F-T7 meets regulatory requirements for computers, industrial robots, and office equipment - all covered under Renesas' RoHS implementation scope.