Supertex inc.

MD0100

Supertex inc.

www.supertex.com

Doc.# DSFP-MD0100

C070113

Features

Applications

General Description

The Supertex 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 15Ω 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.

Typical Application Circuit

High Voltage Protection

T/R Switch

Transmitter

Piezo

Transducers

B

A

Receiver

T

X

R

X

High Voltage

Switches

+90V

-90V

T/R Switch

MD0100

Logic

Control

and

Signal

Processing