- •FEATURES
- •APPLICATIONS
- •DESCRIPTION
- •ABSOLUTE MAXIMUM RATINGS
- •PACKAGE DISSIPATION RATINGS
- •RECOMMENDED OPERATING CONDITIONS
- •ELECTRICAL CHARACTERISTICS: VDD = +5 V
- •ELECTRICAL CHARACTERISTICS: VDD = +2.7V
- •ELECTRICAL CHARACTERISTICS
- •PIN CONFIGURATIONS
- •TIMING INFORMATION
- •TYPICAL CHARACTERISTICS: VDD = +5V
- •TYPICAL CHARACTERISTICS: VDD = +2.7V
- •THEORY OF OPERATION
- •ANALOG INPUT
- •REFERENCE INPUT
- •NOISE
- •AVERAGING
- •DIGITAL INTERFACE
- •SIGNAL LEVELS
- •SERIAL INTERFACE
- •DATA FORMAT
- •POWER DISSIPATION
- •SHORT CYCLING
- •LAYOUT
- •APPLICATION CIRCUITS
ADS8325
www.ti.com
SBAS226C –MARCH 2002 –REVISED AUGUST 2007
TYPICAL CHARACTERISTICS: VDD = +5V
At TA = +25°C, VDD = +5V, VREF = +5V, fSAMPLE = 100kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
INTEGRAL LINEARITY ERROR vs CODE
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ILE(LSBS) |
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−1 |
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−2 |
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−3 |
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0000H |
4000H |
8000H |
C000H |
FFFFH |
Output Code
Figure 2.
FREQUENCY SPECTRUM
(8192 Point FFT, fIN = 1.0132kHz, –0.2 dB)
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Amplitude(dB) |
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−120
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−160
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Frequency (kHz)
Figure 4.
DIFFERENTIAL LINEARITY ERROR vs CODE
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DLE(LSBS) |
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−1 |
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−2 |
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−3 |
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0000H |
4000H |
8000H |
C000H |
FFFFH |
Output Code
Figure 3.
FREQUENCY SPECTRUM
(8192 Point FFT, fIN = 10.0022kHz, –0.2 dB)
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−120
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Frequency (kHz)
Figure 5.
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SIGNAL-TO-NOISE RATIO AND |
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SIGNAL-TO-NOISE + DISTORTION |
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SNR |
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SINADSNRand |
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SFDR(dB) |
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SINAD |
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1 |
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100 |
245 |
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Frequency (kHz) |
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110
105
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95
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85
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SPURIOUS-FREE DYNAMIC RANGE AND |
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SFDR |
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−100 |
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THD(dB) |
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NOTE: (1) First nine |
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harmonics of the |
THD(1) |
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input frequency. |
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245 |
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Figure 6. |
Figure 7. |
10 |
Submit Documentation Feedback |
Copyright © 2002–2007, Texas Instruments Incorporated |
Product Folder Link(s): ADS8325
ADS8325
www.ti.com
SBAS226C –MARCH 2002 –REVISED AUGUST 2007
TYPICAL CHARACTERISTICS: VDD = +5V (continued)
At TA = +25°C, VDD = +5V, VREF = +5V, fSAMPLE = 100kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
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SIGNAL-TO-NOISE + DISTORTION |
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fIN = 1.0132kHz |
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Distortion |
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Noise- |
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Signal |
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−80 |
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−60 |
−50 −40 |
−30 −20 |
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0 |
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Input Level (dB) |
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Figure 8. |
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EFFECTIVE NUMBER OF BITS |
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vs INPUT FREQUENCY |
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15.0 |
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Bitsof |
14.5 |
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14.0 |
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EffectiveNumber |
13.5 |
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13.0 |
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12.5 |
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12.0 |
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11.5 |
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11.0 |
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1 |
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Frequency (kHz) |
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Figure 10. |
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CHANGE IN GAIN |
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vs TEMPERATURE |
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2.0 |
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(LSBS) |
1.5 |
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1.0 |
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25°C |
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0.5 |
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Deltafrom |
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0.0 |
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−0.5 |
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−1.0 |
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−1.5 |
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75 |
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−25 |
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Temperature (°C) |
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Figure 12. |
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PEAK-TO-PEAK NOISE FOR A DC INPUT vs REFERENCE VOLTAGE
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(LSB) |
100 |
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PeakNoise |
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Peak-to- |
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Figure 9. |
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CHANGE IN SIGNAL-TO-NOISE + DISTORTION |
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fIN = 1.0132kHz, −0.2dB |
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0.0 |
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+25°C |
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−0.8 |
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−50 |
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Temperature (°C) |
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Figure 11. |
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CHANGE IN UPO |
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3.0 |
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(LSBS) |
2.5 |
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1.5 |
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25°C |
2.0 |
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1.0 |
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0.5 |
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0.0 |
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−0.5 |
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−1.0 |
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−50 |
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0 |
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Temperature (°C)
Figure 13.
Copyright © 2002–2007, Texas Instruments Incorporated |
Submit Documentation Feedback |
11 |
Product Folder Link(s): ADS8325
ADS8325
www.ti.com
SBAS226C –MARCH 2002 –REVISED AUGUST 2007
TYPICAL CHARACTERISTICS: VDD = +5V (continued)
At TA = +25°C, VDD = +5V, VREF = +5V, fSAMPLE = 100kHz, fCLK = 24 × fSAMPLE, unless otherwise noted.
SupplyCurrent(mA)
SUPPLY CURRENT vs TEMPERATURE
1.1
1.0
0.9
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0.7
−50 |
−25 |
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25 |
50 |
75 |
100 |
Temperature (°C)
12 |
Submit Documentation Feedback |
Copyright © 2002–2007, Texas Instruments Incorporated |
Product Folder Link(s): ADS8325