MD0100 is a high voltage, two terminal, bi-directional, current-limiting protection device. The two terminals are interchangeable. It is designed to protect a low noise receiver from the high voltage transmit pulses in ultrasound applications and is commonly referred to as a T/R (transmit and receive) switch. The MD0100 can be considered as a normally closed switch with a typical switching resistance of 15O that allows small signals to pass. Once the voltage drop across the two terminals exceeds a nominal value of ±2.0V, the device will start to turn off. In the off state, the MD0100 can withstand up to ±100V across its terminals. A small amount of current, typical of 200µA, is allowed to flow through. The applications for the MD0100 are not limited to just ultrasound. It can also be used for resettable fuses to protect power lines, output short circuit protection, and data acquisition. The MD0100 is available in the SOT-89 package as a single channel device for ease of assembly. It is also available in a 4.0x4.0mm 8-Lead DFN package as a two channel device for high density requirements.

• Up to ±100V input voltage protection
• Low on resistance - 15Ω typical
• Fast switching speed
• Effectively, a simple two terminal device
• No external supplies needed