Product details


Number of channels (#) 1 IO capacitance (Typ) (pF) 0.9 Vrwm (V) 3.6 IEC 61000-4-2 contact (+/- kV) 30 IEC 61000-4-5 (A) 6 Features Bi-/uni-directional Uni-Directional IO leakage current (Max) (nA) 10 Rating Catalog Operating temperature range (C) -40 to 125 Dynamic resistance (Typ) (Ω) 0.13 Clamping voltage (V) 6.8 open-in-new Find other ESD & surge protection ICs

Package | Pins | Size

X1SON (DPY) 2 1 mm² .6 x 1 open-in-new Find other ESD & surge protection ICs


  • IEC 61000-4-2 Level 4 ESD Protection
    • ±30-kV Contact Discharge
    • ±30-kV Air Gap Discharge
  • IEC 61000-4-4 EFT Protection
    • 80 A (5/50 ns)
  • IEC 61000-4-5 Surge Protection
    • 6 A (8/20 µs)
  • IO Capacitance: 0.9 pF (Typical)
  • DC Breakdown Voltage: 4.5 V (Minimum)
  • Low Leakage Current: 0.1 nA (Typical)
  • Extremely Low ESD Clamping Voltage
    • 6.8 V at 16 A TLP (I/O to GND)
    • RDYN: 0.13 Ω (I/O to GND)
  • Industrial Temperature Range: –40°C to +125°C
  • Industry Standard 0402 Package (DFN1006P2)
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The ESD321 is a uni-directional TVS ESD protection diode featuring low dynamic resistance and low clamping voltage. The ESD321 is rated to dissipate ESD strikes up to ±30 kV per the IEC 61000-4-2 international standard (greater than Level 4).

The ultra-low dynamic resistance (0.13 Ω) and extremely low clamping voltage (6.8 V at 16 A TLP) ensure system level protection against transient events. This device has a low capacitance of 0.9 pF IO capacitance making it suitable for protecting interfaces such as USB 2.0 and Ethernet 10/100/1000 Mbps.

The ESD321 is offered in the industry standard 0402 (DPY/DFN1006P2) package.

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Technical documentation

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Type Title Date
* Data sheet ESD321 1-Channel 30 kV ESD Protection Diode with Low Capacitance (< 1pF) in 0402 Package datasheet Mar. 07, 2018
Application note ESD Packaging and Layout Guide Aug. 27, 2020
Technical article Top 3 considerations for harsh industrial Ethernet Nov. 04, 2019
White paper Demystifying surge protection Nov. 06, 2018

Design & development

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Hardware development

document-generic User guide
Texas Instrument's ESDEVM evaluation module allows the evaluation of most of TI's ESD portfolio. The board comes with all traditional ESD footprints in order to be able to test any number of devices. Devices that need to be tested can be soldered onto their respect footprint and then tested. For the (...)
  • Allows testing of most TI ESD devices
  • Many footprints to allow testing of each part
  • S-parameter testing for signal integrity

Design tools & simulation

SLVMCQ5.ZIP (30 KB) - S-Parameter Model
PSpice® for TI design and simulation tool
PSPICE-FOR-TI — PSpice® for TI is a design and simulation environment that helps evaluate functionality of analog circuits. This full-featured, design and simulation suite uses an analog analysis engine from Cadence®. Available at no cost, PSpice for TI includes one of the largest model libraries in the (...)
  • Leverages Cadence PSpice Technology
  • Preinstalled library with a suite of digital models to enable worst-case timing analysis
  • Dynamic updates ensure you have access to most current device models
  • Optimized for simulation speed without loss of accuracy
  • Supports simultaneous analysis of multiple products
  • (...)
SPICE-based analog simulation program
TINA-TI TINA-TI provides all the conventional DC, transient and frequency domain analysis of SPICE and much more. TINA has extensive post-processing capability that allows you to format results the way you want them. Virtual instruments allow you to select input waveforms and probe circuit nodes voltages (...)
document-generic User guide

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