Diodes Incorporated DDZ20CS-7

Overview

DDZ20CS-7 from Diodes Incorporated is a surface-mount precision Zener diode with nominal zener voltage 19.23–20.22 V, 10 mA test current, 28 Ω maximum zener impedance at I_ZT, 0.5 µA maximum reverse leakage at 15.0 V, and 200 mW power dissipation in SOD323 package. It provides stable voltage reference in low-power analog monitoring circuits.

For engineers reviewing the DDZ20CS-7 datasheet, DDZ20CS-7 pinout, DDZ20CS-7 application, or DDZ20CS-7 equivalent, key selection criteria include zener voltage tolerance (±2.5%), temperature coefficient (~+0.07%/°C), low leakage at rated VR, thermal resistance (625 °C/W), and compatibility with automated SMT assembly on FR-4 PCBs.

Technical Context

This device operates as a two-terminal voltage reference using avalanche breakdown in silicon. Its sharp knee characteristic and tight V_Z tolerance (±2.5% over 19.23–20.22 V range) enable high-accuracy regulation in feedback paths of DC-DC converters and sensor biasing networks.

Designed for operation at I_ZT = 10 mA, it exhibits 28 Ω dynamic impedance (Z_ZT) and maintains <0.05 µA reverse current at VR = 15.0 V - critical for low-error voltage sensing in battery-powered instrumentation.

Key Specifications

Pinout & Package

DDZ20CS-7 uses the SOD323 plastic surface-mount package with cathode band marking. Dimensions: 1.30 mm × 1.70 mm × 0.95 mm (L × W × H), weight ≈ 0.004 g, moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar zener reference applications.

Compared with BZX84-C20LT1G and MMSZ5249BS-7-F, DDZ20CS-7 delivers tighter V_Z tolerance, lower zener impedance, and lower leakage - making it optimal for high-accuracy, low-power shunt references where board space and thermal performance are constrained.

Availability

DDZ20CS-7 is available at Aetrix Electronics and suitable for industrial sensor conditioning, USB-C power delivery reference design, and portable medical instrumentation requiring stable component supply and consistent SOD323 packaging.

Supply support for DDZ20CS-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 and manufacturing operations across Asia and the Americas.

The DDZ series targets precision voltage reference applications in space-constrained, high-reliability systems - emphasizing tight V_Z tolerance, low leakage, and robust SMT manufacturability.

FAQ

What is the maximum continuous power dissipation for DDZ20CS-7?

DDZ20CS-7 has a rated power dissipation of 200 mW at 25°C ambient when mounted on an FR-4 PCB with the recommended pad layout. Derating begins above 25°C at 0.8 mW/°C, reaching zero dissipation at 150°C ambient per the published derating curve.

Does DDZ20CS-7 have a specified temperature coefficient?

Yes - Figure 14 in the datasheet shows a typical temperature coefficient of +0.07%/°C for DDZ20CS across the 20–30 V range at I_ZT = 5 mA. This value reflects the positive drift rate of zener voltage with increasing junction temperature.

Is DDZ20CS-7 compatible with lead-free reflow soldering processes?

Yes - DDZ20CS-7 is fully RoHS-compliant and rated for lead-free reflow profiles. Its matte tin annealed terminals meet MIL-STD-202 Method 208 solderability requirements and withstand peak temperatures up to 260°C per J-STD-020.

How is polarity identified on the DDZ20CS-7 package?

Polarity is indicated by a cathode band printed on the SOD323 case. The banded end is the cathode terminal; the opposite end is the anode. This marking aligns with industry-standard diode polarity conventions and is visible under 20× magnification.