ESDM1021 ESD Protection Diode

Introduction

The onsemi ESDM1021 is a compact, single-line bidirectional ESD protection diode designed to protect voltage-sensitive connections. Its combination of IEC 61000-4-2 Level 4 protection, up to ±30 kV contact and air-discharge capability, and an exceptionally small X4DFN-2 01005 package makes it relevant where board area and exposure to external handling or interfaces must both be considered.

With a 2.0 V working peak reverse voltage, the device is intended for low-voltage signal and power-line protection, including GPIOs and 1.8 V power rails.

What it does

The ESDM1021 provides one bidirectional protection line. In normal operation, it is specified for a 2.0 V working peak reverse voltage and has 1.0 nA typical reverse leakage current at that voltage, with a 100 nA maximum rating.

During an ESD or transient event, the diode diverts surge current away from the protected node. It is specified for ±30 kV contact and air discharge under IEC 61000-4-2 Level 4 conditions. Its typical TLP clamping voltage is 4.9 V at 8 A and 5.4 V at 16 A. For an 8/20 µs waveform, clamping is specified as 5.3 V typical and 6.5 V maximum at 10 A.

Other transient-related ratings include a 10 A reverse peak pulse current for an 8/20 µs waveform and 313 mW maximum power dissipation at 25°C. The specified dynamic resistance is 0.074 Ω with a 100 ns TLP pulse.

Applications

Potential uses that follow from the device’s stated protection role include:

• Protection of individual GPIO lines exposed to ESD events
• ESD protection for 1.8 V low-voltage power rails
• Protection of voltage-sensitive low-voltage signal nodes
• Space-constrained boards requiring single-line bidirectional protection
• Compact portable or densely integrated electronics where external connections may be handled or exposed

Design considerations

The ESDM1021 is supplied in an X4DFN-2 01005 package measuring 0.445 mm × 0.24 mm × 0.18 mm. This very small footprint can support dense layouts, but it also calls for suitable PCB land patterns, assembly processes, and inspection capability for 01005-scale components.

The 2.0 V working peak reverse voltage should be matched to the normal operating voltage of the node being protected. Designers should also account for the device’s breakdown range of 3.7 V to 5.7 V at 1 mA and its transient clamping behavior when checking the voltage tolerance of the protected circuitry.

For signal applications, the junction capacitance is specified at 18 pF typical and 23 pF maximum at 0 V and 1 MHz. This capacitance should be considered where line loading or signal integrity is important. The device is rated from -55°C to +150°C for junction and storage temperature, with a 400°C/W junction-to-ambient thermal resistance.

Availability and further information

Further technical information is available through the datasheet link on this page. The listed Mouser Electronics source/distributor link can provide additional purchasing and product information.