HP 34970A Matrix Switching, Form C (SPDT) Switching

Chapter 3 System Overview

Signal Routing and Switching

Matrix Switching A matrix switch connects multiple inputs to multiple outputs and therefore offers more switching flexibility than a multiplexer. Use a matrix for switching low-frequency (less than 10 MHz) signals only. A matrix is arranged in rows and columns. For example, a simple 3x3 matrix could be used to connect three sources to three test points as shown below.

Source 1

3

Source 2

Source 3

Test 1 Test 2 Test 3

Any one of the signal sources can be connected to any one of the test inputs. Be aware that with a matrix, it is possible to connect more than one source at the same time. It is important to make sure that dangerous or unwanted conditions are not created by these connections.

Form C (SPDT) Switching The HP 34903A Actuator contains

20Form C switches (also called single-pole,double-throw). You can use Form C switches to route signals but they are typically used to control external devices.

		Channel Open			Channel Closed
	(NC Contact Connected)			(NO Contact Connected)
NO = Normally Open			NO			NO
			NC			NC
NC = Normally Closed
			COM			COM

59