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MDD SMAJ18A
Configuration
1 options
Configuration
26+
Available for RFQ
Technical data
Product details
19
specifications
Core information
- Product name
- MDD SMAJ18A
- Type
- MDD
- Minimum package
- 5000 圆盘
Technical parameters
- Electronic Component
- Electronic Component
- Electronic Component
- MDD
- Electronic Component
- SMAJ18A
- Electronic Component
- 1
- Package
- SMA(DO-214AC)
- Electronic Component
- Electronic Component
- Type
- TVS
- Electronic Component
- ESD and Surge Protection (TVS / ESD)
- Electronic Component
- 0.094g
- Electronic Component
- 1
- Electronic Component
- BM0230596316
- Operating Temperature
- 65℃~+150℃
- Voltage
- 29.2V
- Current(Ir)
- 1uA
- Voltage(VBR)
- 22.1V
- Electronic Component
- Electronic Component
For datasheets, package documents, compatible-part guidance, or other technical resources, contact WMSIC customer service. Availability is confirmed case by case.
SMAJ18A（MDD）TVS二极管产品概述
一、产品简介
SMAJ18A 是 MDD 品牌的一款单向瞬态电压抑制（TVS）二极管，封装为标准 SMA（DO-214AC）。它针对瞬态浪涌和电气过压事件提供快速钳位保护，适用于通讯、汽车电子、工业控制与电源接口等需要对单向直流或低频直流信号保护的场景。
二、主要电气参数
- 极性：单向（适用于有明确正负极的电路）
- 反向截止电压（Vrwm）：18 V
- 击穿电压（Vbr）：22.1 V
- 钳位电压：29.2 V（在规定脉冲条件下测得）
- 峰值脉冲电流（Ipp）：13.7 A @ 10/1000 μs
- 峰值脉冲功率（Ppp）：400 W @ 10/1000 μs（典型电涌波形）
- 反向漏电流（Ir）：1 μA（在 Vrwm 条件下）
- 工作温度范围：-65 ℃ 至 +150 ℃
三、主要特点
- 高能量吸收能力：在 10/1000 μs 浪涌条件下可承受高达 400 W 的瞬态功率，适合防护雷击、开关瞬变等能量较高的冲击。
- 低钳位电压：29.2 V 的钳位能在过压发生时限制被保护节点电压，降低下游器件应力。
- 低漏电流：1 μA 的低反向电流有利于对电池供电或低功耗系统的影响最小化。
- 宽工作温度：-65~+150 ℃，可满足苛刻环境和汽车等级应用的温度要求（需结合系统规范验证）。
四、典型应用
- 汽车车载通信和传感器保护（12 V/24 V 总线防护，需结合汽车认证要求）
- 电源输入端和适配器接口浪涌抑制
- 通信端口（串口、以太网非差分端）与信号线保护
- 工业控制设备、UPS 与电源管理模块的瞬态电压防护
五、选型与使用建议
- 若保护对象为直流供电（有固定极性），优先采用单向 TVS；交流或双向浪涌应选双向型号。
- Vrwm 应略高于系统正常工作电压：例如 12 V 系统选择 18 V Vrwm 可容许正常纹波且能在浪涌时动作。
- 钳位电压应小于被保护器件耐压限值，29.2 V 钳位适用于多数 12 V/24 V 系统，但高压敏感器件需额外验证。
- 布局上应将 TVS 尽量靠近受保护端子或连接口焊接，走线短且粗，减少寄生感抗与感应电压。地线应直接回到公共地或接地铜箔，避免通过长回流路径。
六、可靠性与封装
SMA（DO-214AC）封装在表面贴装中具有良好的热散与机械强度，适合自动贴装与回流焊工艺。储存与焊接要遵循厂家推荐的回流温度曲线，避免超温影响器件特性和应力裂纹。长期在高温或高应力环境下使用应考虑热降额与寿命评估。
七、结论
SMAJ18A（MDD）是一款针对高能量瞬态抑制的单向 TVS 器件，具备较低的钳位电压、较高的浪涌吸收能力与宽温度范围，适合在多种直流系统中作线路和接口保护。选型时应关注 Vrwm 与系统工作电压的匹配、钳位电压对被保护器件的影响以及 PCB 布局与接地设计以发挥最佳保护效果。
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