The CS 2.5 Current Source is a general-purpose current amplifier with a 2.0 A limit and a 4.0 A/V current gain factor. A 1.0 V/A monitor output allows the user to detect the actual current being output by the CS 2.5. In addition to current output in response to voltage input, the CS 2.5 can be programatically ordered to a DC output current of a maximum of 2.0 A, with no voltage input.
The CS 2.5 also offers two independently-programmable DC voltage output ports - Field Bias 1 and Field Bias 2 - with limits of ±10.0 Volts. Voltage output is also programmatically controlled.
Although the CS 2.5 serves as a general-purpose current and voltage source, it was developed in conjunction with the Magneto-Electric measurement bundle and is included in sales of the ME bundle. In this use, the current output is fed through a commercial Helmholtz Coil that generates a magnetic field that is linearly related to the current through the coil. A 6" Lakeshore MH-6 Helmholtz Coil, with a gain factor of approximately 26.0 G/A, is provided as standard with the Magneto-Electric bundle.
In conjunction with the magnetic field application of the CS 2.5, the Field Bias-1 and Field Bias-2 port are provided as input voltage to commercial current amplifiers that normally drive fixed electromagnets. The standard sample response to a variable magnetic field generate in the Helmholz Coil is often taken inside a larger magnetic field generated by fixed electromagnets. Such fixed magnets are not normally provided as part of the Magneto-Electric bundle.
The Vision program includes the following Tasks that directly control the CS 2.5 Current Source:
CS 2.5 DC Current/Magnetic Field - This Task generates a fixed DC current output of a maximum of 2.0 A. The output may be specified in units of Current (A) or of Magnetic Field (G). If Magnetic Field (G) is specified the user provides the Helmholtz Coil's Magnetic Field (G)/Current (A) gain ratio. For this Task the CS 2.5 generates its output current (A) programmatically and takes no voltage input.
CD 2.5 DC Voltage/Magnetic Field - The Task programatically generates fixed output voltages at the CS 2.5 Field Bias - 1 and/or Field Bias - 2 ports. The output voltage may be specified either in units of Volts or as Magnetic Field (G) with the electromagnet Field (G)/Volt ratio specified.
Magneto-Electric Response - This Task is similar to the Hysteresis Task. It generates a charge response in the sample. In this case, the response is induced by a variable magnetic field (G) from the Helmholtz coil, stimulated by a voltage input/current output at the CS 2.5. The user must provide the desired maximum magnetic field (G), the Helmholtz Coil's Field (G)/A ratio and the CS 2.5 Current (A)/Volt ratio. The Current (A)/Volt ratio is stored in the CS 2.5 EEPROM and is updated automatically in the Task configuration dialog. The current output of the CS 2.5 is stimulated by the tester's DRIVE port output, whose voltage DRIVE profile is determined by Vision based on the mentioned parameters and ratios. The Task may also be configured to apply a DC magnetic field using voltage-controlled electromagnets.
Single-Point C/V (MR) - This is a conventional electrical single-point C/V measurement that has the additional component in the ability to control a DC magnetic field though external electromagnets and the Field Bias - 1 or Field Bias - 2 port. The user may also opt to apply a DC current programmatically.
