ADC

Photo: Analog-to-digital Converter (ADC)

The ADC unit receives an analog signal (voltage), converts it into a digital code and transmits it to a personal computer. The processing program installed on a personal computer provides the operator with the functions of visual observation of the chromatogram, mathematical methods of its processing and storage methods. The ADC unit for chromatograph of LHM type “Tsvet” series is assembled on the basis of 24-bit ADC.

ADC unit for chromatograph: specifications

• Number of analog inputs — from 1 to 8.
• Data exchange with personal computer — via standard RS-232C interface.
• Input resistance - not less than 1×106 Mohm.
• Voltage resolution - 4,768 mcV/code unit (number of effective discharges — 19). Linear dynamic voltage range - not less than 0,5×10⁶. When you connect an external electrometric amplifier with automatic switching of measurement limits, the dynamic range is expanded by 100 times. Switching control-automatic.
• Input voltage range-from minus 2,5 to 2,5 V.
• The minimum measured half-width of the chromatographic peak is 0,5 s.
• The level of fluctuation noise given to the input is not more than 1×10^-5 V.
• Reduced error of linear signal conversion-no more than ±0,1 %.
• Electrical power from a single-phase AC voltage from 187 to 242 V, frequency (50±1) Hz, mode of operation-continuous.
• Power consumption (without personal computer), no more — 15 VA.
• Overall dimensions (width×depth×height), not more than — 300×215×60 mm.
• Weight, not more — 2,7 kg.