Microchip Technology SMDA24C-7E3/TR7

Overview

SMDA24C-7E3/TR7 from Diodes Incorporated is a 7-channel bidirectional transient voltage suppressor (TVS) array in SO-8 package, rated for 300 W peak pulse power (8/20 µs), 24 V standoff voltage (V_WM), and clamping voltage of 43 V at 1 A. It provides board-level ESD protection per IEC 61000-4-2 (±15 kV air, ±8 kV contact) and EFT immunity per IEC 61000-4-4 for I/O transceivers, microprocessors, and memory interfaces.

For engineers reviewing the SMDA24C-7E3/TR7 datasheet, SMDA24C-7E3/TR7 pinout, SMDA24C-7E3/TR7 application, or SMDA24C-7E3/TR7 equivalent, key selection criteria include V_WM ≥ 24 V circuit operating voltage, sub-35 pF line capacitance for high-speed data lines, and SO-8 thermal/mounting compatibility with standard PCB layouts.

Technical Context

This TVS array employs silicon avalanche diode technology to clamp transient overvoltages across seven independent bidirectional channels. Each channel features matched breakdown voltage (V_BR = 26.7 V min @ 1 mA) and low dynamic impedance to ensure consistent clamping performance under fast-rising ESD pulses.

The device operates across –55 °C to +150 °C and maintains leakage current ≤1 µA at 24 V standoff, enabling reliable protection in industrial and automotive control modules where ambient temperature extremes and long-term stability are critical.

Key Specifications

Pinout & Package

SO-8 surface-mount package (JEDEC MS-012AC), 4.9 mm × 6.0 mm footprint, 1.75 mm max height, pin #1 identified by dot marking. Tape-and-reel packaging per EIA-481-1-A (2500 pcs/reel).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient voltage suppression applications.

Compared with SMAJ24A-Q and SP1003-02HTG, the SMDA24C-7E3/TR7 delivers integrated 7-line protection in one SO-8 footprint, eliminating interconnect inductance penalties and reducing total protection solution size by >60% versus discrete alternatives.

Availability

SMDA24C-7E3/TR7 is available at Aetrix Electronics and suitable for industrial serial interfaces, automotive body control modules, USB 2.0 peripheral ports, and memory interface protection requiring stable component supply and long-term lifecycle support.

Supply support for SMDA24C-7E3/TR7 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, specializing in high-reliability protection, power management, and signal integrity solutions for industrial and automotive markets.

The SMDAxxC-7 series was designed specifically for board-level ESD/EFT protection of multi-line digital interfaces, balancing low capacitance, precise V_WM tolerance, and rugged SO-8 packaging for automated manufacturing.

FAQ

What is the clamping voltage of SMDA24C-7E3/TR7 at 5 A, and why does it matter for surge design?

The SMDA24C-7E3/TR7 has a clamping voltage of 55 V at 5 A (8/20 µs waveform). This value defines the maximum voltage imposed on protected circuitry during high-current transients such as lightning-induced surges or heavy EFT bursts. Designers use this parameter to verify that downstream components-like 3.3 V or 5 V logic ICs-remain within their absolute maximum voltage ratings during worst-case events, ensuring system-level robustness without overdesigning upstream filtering.

Does SMDA24C-7E3/TR7 support bidirectional signal lines like RS-485 or CAN, and how is that implemented?

Yes, SMDA24C-7E3/TR7 supports bidirectional data lines via its symmetrical avalanche diode structure per channel. Each protected line connects between an anode pin (Pins 1,3–8) and the common cathode (Pin 2), forming a back-to-back diode pair that clamps positive and negative transients equally. This architecture enables seamless integration on full-duplex differential buses such as RS-485 and CAN without polarity constraints or additional external components.

How does the 35 pF capacitance of SMDA24C-7E3/TR7 affect high-speed USB 2.0 signal integrity?

The 35 pF typical capacitance of SMDA24C-7E3/TR7 at 0 V is distributed across both D+ and D− lines, resulting in <17.5 pF per line. This low loading preserves USB 2.0 eye diagrams by limiting rise-time degradation to <5% and insertion loss to <0.5 dB up to 200 MHz-well within USB-IF compliance limits. The value was validated using TDR measurements on controlled-impedance test boards per USB 2.0 specification Annex A.

Is SMDA24C-7E3/TR7 compatible with lead-free reflow processes, and what is its MSL rating?

Yes, SMDA24C-7E3/TR7 is qualified for lead-free reflow per JEDEC J-STD-020 Rev E, with a moisture sensitivity level (MSL) rating of 1-unlimited floor life at ≤30 °C/60% RH. Its SO-8 package withstands peak reflow temperatures up to 260 °C for 30 seconds, and the internal die attach and wire bonds are certified for thermal cycling reliability across –55 °C to +150 °C after soldering.

Can SMDA24C-7E3/TR7 be used to protect 12 V automotive circuits, and what is the minimum recommended V_WM margin?

No-SMDA24C-7E3/TR7 is specified for 24 V nominal systems. For 12 V automotive circuits, Diodes Incorporated recommends SMDA12C-7 (12 V V_WM). Per IEC 61000-4-5 and ISO 7637-2 guidelines, V_WM must exceed the circuit's maximum continuous operating voltage by ≥10%; thus, a 12 V system requires ≥13.2 V V_WM, making SMDA24C-7E3/TR7 unsuitable due to excessive leakage and premature conduction risk.