They say:=0A=
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The circuits shown here utilize ultralow noise 24-bit Sigma-Delta ADCs with=
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internal PGA and drivers, to design precision weigh scale systems spanning=
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low- and high-speed applications. The sigma-delta ADCs simplify the weigh=
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scale design because most of the system building blocks are included on the=
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chip. An appropriate low drop-out linear regulator is specified for use, an=
d=0A=
the benefits of each circuit are described below. Visit the individual=0A=
circuit note pages to learn more.=0A=
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http://www.analog.com/en/content/Weigh_Scale_Circuit_Diagrams/fca.html=0A=
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 One of two lowest noise from this collection, with RMS noise =3D 8.5 nV @ =
4.7=0A=
Hz. Supports ac and dc excitation of the loadcell. AD7195: 4.8 kHz, Ultralo=
w=0A=
Noise, 24-Bit Sigma-Delta ADC with PGA and AC Excitation, $6.901=0A=
ADP3303: 200 mA low drop-out linear regulator, $1.11=0A=
CN0155<http://www.analog.com/en/circuits-from-the-lab/CN0155/vc.html>=0A=
2(shown below) One of two lowest noise from this collection, with RMS noise=
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=3D 8.5 nV @ 4.7 Hz. Supports dc excitation of the loadcell only. AD7190: P=
in=0A=
programmable low noise 24-bit =D3-=C4 ADC with PGA, $5.901=0A=
ADP3303: 200 mA low drop-out linear regulator, $1.11=0A=
CN0102<http://www.analog.com/en/circuits-from-the-lab/CN0102/vc.html>Slight=
ly=0A=
higher noise level (11 nV @ 4.7 Hz), but lower in power, cost.AD7192:=0A=
4.8 kHz Ultra-Low Noise 24-Bit =D3-=C4 ADC with PGA, $4.90=0A=
ADP3303: 200 mA low drop-out linear regulator, $1.11=0A=
CN0119<http://www.analog.com/en/circuits-from-the-lab/CN0119/vc.html>Easier=
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circuit to implement due to pin programmability. RMS Noise =3D 15 nV @=0A=
10 Hz AD7191: 24-bit pin-programmable =D3-=C4, $3.80=0A=
ADP3303: 200 mA low drop-out linear regulator, $1.11=0A=
CN0118<http://www.analog.com/en/circuits-from-the-lab/CN0118/vc.html>Low=0A=
power and low noise: RMS Noise =3D 49 nV @ 10 Hz and power at 330 uA=0A=
typical AD7780: Pin Programmable 24-Bit =D3-=C4 ADC with PGA and pin reset,=
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$2.70=0A=
ADP3303: 200 mA low drop-out linear regulator, $1.11=0A=
CN0107<http://www.analog.com/en/circuits-from-the-lab/CN0107/vc.html>=0A=
2 Also low power (330uA) and low noise (49nV rms noise @10Hz). Plus, lowest=
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price in collection. AD7781: Pin Programmable 20-Bit =D3-=C4 ADC with PGA a=
nd=0A=
pin reset, $1.95=0A=
ADP3303: 200 mA low drop-out linear regulator, $1.11=0A=
CN0108<http://www.analog.com/en/circuits-from-the-lab/CN0108/vc.html>=0A=
2=0A=
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