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PROTECTION PRODUCTS

SDC36

Device Connection for Protection of Two, Three, and

Four Wire Proximity Switches

Digital sensors help to bridge the gap between the

physical world and the digital world in applications such

as computer controlled factory automation. In such

environments, transient voltages can easily disrupt or

damage sensitive sensor inputs. The SDC36 provides

transient voltage protection for the digital sensors to

ensure their operation is not disrupted by the physical

world.

The SDC36 is designed to meet the high surge capabil-

ity and low clamping voltage needed to protect the

ASIC and control logic used in proximity switches. The

SDC36 provides protection for the power and I/O lines.

Typical configurations for the protection of two, three,

and four wire switches are as follows:

1. Two-Wire Switch: Connect pin 1 to the I/O line and

pin 2 to the DC supply (since the device is symmetrical,

these connections can be reversed). Pin 3 is not

connected.

2. Three-Wire Switch: Either pin 1 or pin 2 is con-

nected to the I/O line with the other connected to

ground. Pin 3 must be connected to the DC supply.

3. Four-Wire Switch: Two device are required to

protect four wire switches. Pin 3 of each device is

connected to the DC supply line. Pins 1 & 2 are

connected to the I/O lines & ground as shown.

2-Wire DC Proximity Switch Application

3-Wire DC Proximity Switch Application

4-Wire DC Proximity Switch Application

Applications Information