Diodes Incorporated ZMM5229B-7

Overview

ZMM5229B-7 from Diodes Incorporated is a 4.3 V, 500 mW surface-mount Zener diode in MiniMELF (DO-213AA) package, rated for 20 mA test current with 22 Ω dynamic impedance at 20 mA and 5.0 µA maximum reverse leakage at 1.0 V, used for precision voltage reference and overvoltage protection in low-power analog circuits.

For engineers reviewing the ZMM5229B-7 datasheet, ZMM5229B-7 pinout, ZMM5229B-7 application, or ZMM5229B-7 equivalent, key selection criteria include zener voltage tolerance (±5%), temperature coefficient (−0.055 %/°C), thermal resistance (300 °C/W), and MiniMELF mechanical compatibility in space-constrained PCB layouts.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage regulation under varying load and temperature conditions. Its −0.055 %/°C temperature coefficient ensures minimal drift across −65 °C to +175 °C operating range, and its 22 Ω zener impedance at 20 mA supports tight regulation in feedback networks.

The device uses hermetic glass MiniMELF packaging for high reliability and moisture resistance, with cathode band polarity marking and solderability compliant to MIL-STD-202, Method 208. Thermal performance is characterized by 300 °C/W junction-to-ambient resistance under natural convection.

Key Specifications

Pinout & Package

MiniMELF (DO-213AA) glass-body surface-mount package with axial cathode band marking; no discrete pins - two solderable end terminals only.

Key Features

Applications

Availability

ZMM5229B-7 is available at Aetrix Electronics and suitable for industrial sensor conditioning, USB-C power delivery protection, automotive body control modules, and medical wearable battery monitoring requiring stable component supply across extended temperature ranges.

Supply support for ZMM5229B-7 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 centers across Asia and manufacturing in Taiwan and China.

The ZMM52xxB series belongs to Diodes' precision Zener diode product line, engineered for high-stability voltage reference and clamping applications where tight tolerance, low tempco, and hermetic reliability are critical.

FAQ

What is the maximum continuous reverse current the ZMM5229B-7 can handle without degradation?

The ZMM5229B-7 is rated for 20 mA test current (I_ZT) and may be operated continuously up to 500 mW dissipation, corresponding to ~116 mA at 4.3 V in ideal thermal conditions. However, sustained operation above 20 mA requires careful thermal design due to 300 °C/W R_JA; typical designs limit average current to ≤15 mA for long-term reliability.

Can ZMM5229B-7 replace ZMM5229B in a PCB layout?

Yes - the "-7" suffix denotes tape-and-reel packaging per EIA-481 standard and does not affect electrical or mechanical specifications. Both share identical MiniMELF (DO-213AA) dimensions, zener characteristics, and thermal ratings; only packaging format differs.

How does the −0.055 %/°C temperature coefficient impact accuracy over −40 °C to +125 °C?

Over this 165 °C span, the total voltage drift is approximately ±0.055 × 165 ≈ ±9.1 mV from nominal 4.3 V - a ±0.21% full-scale shift. This is verified in Diodes' DS30024 characterization data and remains within specification for most non-calibrated analog references.

Is ZMM5229B-7 suitable for use as a voltage reference in a 12-bit ADC system?

Yes - with its 4.3 V ±5% tolerance, −0.055 %/°C tempco, and 22 Ω impedance, it delivers <±12 mV total error over industrial temperature range, supporting effective resolution better than 11 bits when used with proper filtering and low-noise layout. For true 12-bit accuracy, external trimming or calibration is recommended.