ER175_Waveform_Generator
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• Interactive operation • Output pulses, ramps, triangles, and sine waves • Define initial conditions • Ideal for cyclic voltammetry • Works with many types of potentiostat • Serial interface protocol with USB connection The eDAQ Waveform Generator 175 is designed to produce relatively slow waveforms where the user can manually interact with the experiment to pause or reverse the applied waveform. The Waveform Generator can be used with an e-corder unit (via the I2C connection) and eDAQ Chart software (v5.5.9 or later). Alternatively it can be used with its AC mains adaptor, and serial compatible software (RS232), via the computer USB port (a virtual serial port is created) — such as: Pulses, ramps, triangles and sinusoidal waveform can be defined with amplitudes up to ±10 V. In addition the triangle function can be started at any arbitrary value. • LabVIEW™, www.ni.com Waveforms are generated by an internal DAC at clock speed of 10 kHz with 22 bit resolution. TTL (or contact closure) signals are provided to synchronize the waveform with other laboratory devices (eg dropping mercury electrodes, third party potentiostats, light sources, stirrers, etc). • Tera Term, http://logmett.com/ • WinWedge®, www.taltech.com/products/winwedge.html or with your own software written in Visual Basic or C++ etc. Applications The Waveform Generator is ideal for cyclic and linear sweep voltammetry where the user may wish to reverse, or pause, the sweep during the experiment. It can also be used to set up a series of voltage levels, each over a different duration, and to repeat this sequence if required. Other applications include vibration and servo-control loop testing. The eDAQ Waveform Generator (model ER175 ) includes hardware unit, cables and 12 V DC mains adaptor. Computer Requirements The computer should have a spare USB port for direct connection of the Waveform Generator, or for connection to an e-corder with which the Waveform Generator is being used. Windows XP, VISTA or 7 is required for use with an e-corder system. Start/Stop Reverse direction Figure 2. Control panel provided by Chart software. WaveForm Generator Mode Trigger Trigger input Grounding post Screw terminal connector Figure 1. Front and back panels of the Waveform Generator. Power on/off Figure 3. Triangular waveform with pre- and post-voltage levels.

Serial Communications The Waveform Generator is fitted with a USB port. This can then be used as a virtual serial port with Windows, Mac OSX, and Linux computers. A Windows USB driver for most Windows computers is located on the eDAQ Software Installer disk supplied with the Waveform generator. Otherwise you can download a suitable driver from Software can then be written to communicate with the Waveform Generator as a serial (RS232) device, for example using LabView, Visual Basic, or C++. The serial port number must first be established. Serial Ports 1 and 2 on Windows computers are...

Table 1. Output functions available for synchronization with an external device. Low TTL pulse, or brief CC closed, at start of pre period TTL pulse, or brief CC closed, at start of function TTL high, CC closed, from start of pre period to end of the post period TTL high, CC closed, from end of pre period to start of the post period TTL high, CC closed, when a triangle or sine function is increasing TTL high, CC closed, when a triangle or sine function is decreasing TTL pulse, brief CC closed, at upper or lower limit of triangle function TTL pulse, brief CC closed, at end of each main...

Specifications Available logic signals: Waveform signal Low, High, Pulse at Run, Pulse at Function, Entire Run, Function Synch, Slope is Positive, Slope is Negative, Pulse per Cycle Auxiliary power: Two +5 V outputs @ 100 mA maximum each Preconditioning levels: 4 (Chart software) 20 (serial protocol commands) Output signal: Output accuracy: Output current: Pulse, ramp, triangular, sine Postfunction levels: Ramp and triangle sweep rates: < 1 mV/h to 1 V/s (with 0.1 mV steps) 10 V/s (with 1 mV steps) 4 (Chart software) 20 (serial protocol commands) Function cycles: Repeat loops: Waveform...