ADC-20 PICO TECHNOLOGY, ADC-20 Datasheet - Page 47

• Manufacturer Part Number: ADC-20
• Description: DATALOGGER, HI-RES
• Manufacturer: PICO TECHNOLOGY

Specifications of ADC-20

• Connector Type: D25 Female
• Interface: USB 1.1 (USB 2.0 Compatible)
• No. Of Channels: 8
• Power Supply: From USB
• Resolution: 20 Bits
• Interface Type: USB 1.1 (USB 2.0 Compatible)
• Rohs Compliant: NA
• Lead Free Status / RoHS Status: na

ADC-20/ADC-24 User's Guide
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LSB. Least significant bit. In a binary word, the least significant bit has the value 1.
MSB. Most significant bit. In an n -bit binary word, the most significant bit has the
value 2^( n -1).
Noise-free resolution. Any measurement is subject to noise. In a digital measuring
instrument, a result with a resolution of n bits may include m bits of noise. The noise-
free resolution is then n-m bits.
Noise rejection. The ability of the data logger to attenuate noise in a given frequency
range. The ADC-20/ADC-24 can be programmed to reject noise at either 50 hertz or
60 hertz. The noise rejection ratio is defined as:
NRR(dB) = 20 log10 (Vin/Vmeas)
where NRR(dB) is the noise rejection ratio in decibels, Vin is the noise voltage at the
input, and Vmeas is the noise voltage that appears in the measurement.
Overload protection. Overload protection is characterised by the maximum voltage
that can be applied across the inputs of the data logger without causing damage to it.
The ADC-20 and ADC-24 are protected to +/- 30 V.
Resolution. A value, in bits, indicating the number of unique digital values that the
converter can produce. If the resolution is n bits, then the number of unique values is
2 to the power n.
RH. Relative Humidity. RH is the ratio of the amount of water vapor in the air to the
maximum amount of water vapour that the air could hold at the current temperature.
USB. Universal Serial Bus. USB is a standard port that enables you to connect
external devices to PCs. A typical USB 1.1 port supports a data transfer rate of 12
megabits per second, making it much faster than an RS-232 COM port.
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