Diodes Incorporated BZT585B24TQ-7

Overview

BZT585B24TQ from Diodes Incorporated is a precision Zener diode with 24 V nominal breakdown voltage (±2.0% tolerance), 350 mW power dissipation, and SOD523 package. It operates across –65 °C to +150 °C, features 70 Ω dynamic impedance at 5 mA test current, and delivers stable voltage reference in automotive-grade power regulation and overvoltage protection circuits.

For engineers reviewing the BZT585B24TQ datasheet, BZT585B24TQ pinout, BZT585B24TQ application, or BZT585B24TQ equivalent, key selection criteria include Zener voltage accuracy, thermal stability (24.4 mV/°C tempco), low reverse leakage (≤0.05 µA @ 16.8 V), and AEC-Q101 qualification for automotive electronics.

Technical Context

This Zener diode uses silicon planar construction to achieve tight 2.0% V_Z tolerance and low temperature coefficient (24.4 mV/°C) at 5 mA. Its SOD523 package enables high power density (350 mW) with minimal footprint and low thermal resistance (357 °C/W).

The device exhibits 55 pF capacitance at 0 V and 1 MHz, supports 200 mA forward current, and maintains ≤0.05 µA reverse leakage up to 16.8 V - enabling use in low-noise voltage clamping and precision biasing where leakage-induced error must be minimized.

Key Specifications

Pinout & Package

Package: SOD523 - ultra-compact surface-mount plastic package (1.25 mm × 0.85 mm × 0.65 mm), flat lead design, matte tin annealed terminals, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ5249B-7-F and BZX84-C24, BZT585B24TQ offers superior voltage accuracy and automotive qualification in the smallest footprint - making it optimal for space-constrained, safety-critical 24 V systems where regulation stability is paramount.

Availability

BZT585B24TQ is available at Aetrix Electronics and suitable for automotive ECUs, industrial sensor transmitters, telecom line cards, and medical infusion pump power supervision requiring stable component supply and full traceability.

Supply support for BZT585B24TQ 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.

The BZT585 series belongs to Diodes' precision Zener portfolio, engineered specifically for automotive and industrial applications demanding high accuracy, low leakage, and AEC-Q101 compliance in miniature packages.

FAQ

What is the maximum continuous reverse voltage this Zener can safely clamp?

The BZT585B24TQ is rated for 24 V nominal Zener voltage with a guaranteed range of 23.52–24.48 V at 5 mA. Its absolute maximum reverse voltage is defined by its power limit: at 25 °C ambient, it sustains ≤350 mW, so sustained clamping above ~24.5 V requires derating per the published power derating curve. Exceeding 16.8 V reverse bias yields ≤0.05 µA leakage - confirming safe operation below breakdown.

Is this part suitable for use in a 24 V CAN bus power rail protector?

Yes - the BZT585B24TQ's AEC-Q101 qualification, -65 °C to +150 °C operating range, and 24 V Zener voltage align with CAN FD physical layer power rail protection requirements. Its 55 pF capacitance avoids signal integrity degradation on 5 Mbps CAN buses, and its 70 Ω impedance ensures fast, stable clamping during ESD transients per ISO 10605.

How does the SOD523 package affect thermal performance compared to SOD-123?

The SOD523 package delivers 350 mW power dissipation despite its smaller size due to optimized thermal path design: junction-to-ambient thermal resistance is 357 °C/W on FR-4 with minimum recommended pads. In contrast, typical SOD-123 Zeners achieve ~500 mW but require ~2.5× more board area and exhibit ~250 °C/W R_θJA - meaning the BZT585B24TQ achieves higher power density without sacrificing thermal margin.

Does this Zener diode require external current limiting in series?

Yes - like all Zener diodes, the BZT585B24TQ requires a series current-limiting resistor to set the operating point within its specified test current (5 mA) and avoid exceeding 350 mW dissipation. For example, with a 28 V supply, a 820 Ω resistor limits current to ~4.9 mA, keeping power at ~118 mW and ensuring stable 24 V regulation without thermal runaway.