Thông tin sản phẩm
The amplifiers have very low offsets for accurate tracking of programming instructions and exceptionally stable output in fixed applications. Voltage may be operationally controlled using the built-in stable reference and summing resistance together with an external voltage feedback rheostat.
The ratio of reference voltage to summing resistance gives a control current of approximately 1 milliampere through the external voltage feedback rheostat, for a control ratio of 1000 ohms/V. (A built-in calibrating trimmer can be used to calibrate this value).
PAT models have a built-in current sensing and feedback arrangement for protective limiting, controlled by an internal trimmer over the range 10% to 105% Io. Terminals are provided on the barrier strip for external control of the current limit function, using either a 3-terminal potentiometer or a 0-1V control voltage.
For a wider current control range, the main channel of the PAT may be connected so as to sample the drop across an external current-sensing resistor in the plus output lead. An external rheostat with careful zeroing of the built-in zeroing potentiometer will control current from 1µA to 100% Io. (Note: the range of currents controlled by any single current-sensing resistor should be limited to a 50:1 ratio).
Operationally, the PATs are 3-terminal, unipolar, inverting d-c amplifiers in which the plus output sensing terminal serves as common between the output and an external programming signal. For isolated digital control, see Kepco SN and SNR Series.