A395 Linear Stimulus Isolator Replicates a programmed waveform of any shape or polarity Current Delivery —A 10 V input produces the maximum output current for the current range selected, i.e., 100 µA, 1 mA, or 10 mA. Front panel controls allow DC current to be generated. Externally applied signals can be superimposed simultaneously (DC offset). Warning lamps indicate open circuit or excessive current conditions. Digital Meter — Measures DC or average output current. Overload Lamps — Indicate when output voltage has reached positive or negative compliance voltage limit. A395RC SYS-A395D SYS-A395R SYS-A362 A395R with Charger (A362) Linear Stimulus Isolator Linear Stimulus Isolator, Rechargeable Battery Charger Specify line voltage All WPI stimulus isolators are designed to supply constant current because current threshold (not voltage) is the most quantitatively reproducible parameter for stimulation of nerve and muscle. Model A395 dispenses current reproducibly from its Output terminals; the amplitude being determined by the selected current RANGE and the input voltage. Current amplitude is “constant”, that is, load resistance independent, provided that the I x R (load) product does not exceed the available battery supply voltage. A visual indicator (the compliance LEDs) displays if I x R reaches this limit. When the unit is out of compliance, one of the two LEDs (labeled - and +) illuminate, depending in which direction the current is flowing. Model A395 D can generate a voltage of 70 volts or more across its OUTPUT terminals. Thus, the user can be sure that the amplitude of the current will be as dialed as long as the voltage drop across the load (stimulus electrode path) does not reach the magnitude of the supply voltage. The compliance LEDs will then be visible. The user would then know that (a) too much current was dialed for a given load or (b) inter-electrode resistance was too high or the electrode circuit path was open. Model A395 generates an output current of arbitrary (user-defined) wave shape; DC, AC, pulse, and combinations thereof. Battery operated, and photoelectrically-isolated from the input voltage drive, the instrument regenerates output currents which are linearly proportional to the analog voltage waveforms provided by your D/A converter or signal generator (see diagram below). The A395 is ideally suited for data acquisition and stimulator generators. It can be easily daisy-chained for mutiple channel requirements. STIMULATORS, ISOLATORS OUTPUT CURRENT, Imax OUTPUT BANDWIDTH R) INPUT RESISTANCE INPUT VOLTAGE @ Imax A395 SPECIFICATIONS 3 ranges: 100µA, 1 mA, and 10 mA ± 70 V 10 kHz (measured across 1KΩ load > 20 MΩ ± 10 volts < 0.5% 26 µs @ 10 KΩ 17 alkaline 9 V batteries 17 rechargeable NiMH 9 V batteries 6.5 x 4 x 3.5 in. (16 x 10 x 9 cm) 4 lb (1.8 kg) OUTPUT VOLTAGE RANGE INPUT/OUTPUT LINEARITY ERROR RISE, FALL TIME POWER Model A395D Model A395R DIMENSIONS SHIPPING WEIGHT INPUT 10 V 0V -10 V +100 µA, +1 mA, +10 mA A362 Battery Charger Required for A320R, A365R and A395R Recharges the high-voltage nickel-cadmium or NiMH battery stack in the A320R, A365R or A395R. LED lamp indicates charging status. Full charge overnight. Dimensions: 2.8 x 4.1 x 5 in. (7 x 10.5 x 12.7 cm). Shipping weight: 4 lb (1.8 kg). OUTPUT 0 -100 µA, -1 mA, -10 mA pts Acce og anal t inpu UK: Tel: +44 (0)1462 424700 • wpiuk@wpi-europe.com World Precision Instruments www.wpiinc.com Germany: Tel: +49 (0)30-6188845 • wpide@wpi-europe.com US: Tel: 941-371-1003 • sales@wpiinc.com 93