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Overview

1.2

Recommended Starter System

The Multi-Cal-System starter system is an eight-channel system for calibrating PGA308 and PGA309

sensor modules automatically. The starter system allows you to verify that the Multi-Cal-System meets

your specific application requirements. You can expand the capacity of your system later by adding slave

boards. Each slave board adds another eight channels, for a maximum system capability of 64 channels

(one master and seven slave boards). Table 1 describes the recommended starter system and lists the

quantities of each board required.

Table 1. Recommended Starter System

Quantity

Name

Comments

1

Multi-Cal-Master EVM

This basic board gives you eight channels.

You may choose to build your own cable

because of cable length requirements. The

2

Multi-Cal-Interface cable

construction of the cable is given in the

Multi-Cal System Cable user

's guide

(SBOU092).

You may choose to build your own cable

because of cable length requirements. The

1

Multi-Cal-Power cable

construction of the cable is given in the

Multi-Cal System Cable user

's guide

(SBOU092).

Depending on the mechanical requirements of

1

Multi-Cal-Interface EVM

your specific system, you may develop your

own interface board.

Two Multi-Cal-Test EVMs allow you to check

two channels. This option is typically enough

2

Multi-Cal-Test EVM

(1)

for initial evaluation of the system. Eight units

would allow you to fully test all eight channels

of the starter system.

(1)

The Multi-Cal-Test EVM board uses the PGA308. The equivalent PGA309 test board does not exist at

the time of this writing; it is currently under development.

There are also several additional pieces of test equipment required; Table 2 summarizes this equipment.

Table 2. Additional Test Equipment Required

Name

Comments

This is power for the multiplexers on the Multi-Cal-Master board. This

supply can range from

±12 V to ±16 V. Choose a low-noise linear

supply for best performance. This supply also powers slave boards if

you expand the system in the future. Keep in mind the current output

capability.

±15V Supply

Current requirement for Master = 150 mA

Current for each Slave = 150 mA

Example: For eight channels and one master = 150 mA

Example: For 64 channels (one master and seven slaves) = 8 x 150

mA = 1.2 A

This supply can range from 5V to 40V, depending on your sensor

module requirements. This power will be directly connected to the

sensor modules. Choose a low-noise linear supply for best

performance. Keep in mind the current output capability. All sensor

modules are powered simultaneously, so multiply the number of

Loop or DUT Power Supply

channels by the expected device current to determine the

requirements.

Example: For eight current loop modules: Assume that maximum

current = 25mA (overcurrent range); 8 x 25 mA = 20 0mA

Example: For 64 current loop modules: 64 x 25 mA = 1.6 A

Must allow for software control through RS-232 or IEEE488.

Precision Digital Multimeter

Suggested instrument is the Agilent 34401A.

This controller is not required if you are using RS-232 control. This

item is a National Instruments IEEE488 controller. It allows you to

GPIB-USB-HS

connect your computer to the precision multimeter for automatic

control.

7

SBOU087A

– August 2010 – Revised April 2011

Multi-Cal-System Evaluation Module

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