adc1112d125 NXP Semiconductors, adc1112d125 Datasheet - Page 21

• Manufacturer Part Number: adc1112d125
• Description: Adc1112d125 Dual 11-bit Adc; Cmos Or Lvds Ddr Digital Outputs
• Manufacturer: NXP Semiconductors

NXP Semiconductors
ADC1112D125
Product data sheet
Fig 21. Internal reference, 2 V (p-p) full-scale
Fig 23. External reference, 1 V (p-p) to 2 V (p-p)
full-scale
11.3.2 Programmable full-scale
11.3.3 Common-mode output voltage (V
V
330 pF
SENSE
VREF
VDDA
0.1 μF
SENSE
The full-scale is programmable between 1 V (p-p) to 2 V (p-p) (see
Table 13.
A 0.1 μF filter capacitor should be connected between pin VCMA/VCMB and ground to
ensure a low-noise common-mode output voltage. When AC-coupled, pin VCMA/VCMB
can then be used to set the common-mode reference for the analog inputs, for instance
via a transformer middle point.
VREF
INTREF
000
001
010
011
100
101
110
111
EQUIVALENT
REFERENCE
SCHEMATIC
REFERENCE
EQUIVALENT
SCHEMATIC
Programmable full-scale
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All information provided in this document is subject to legal disclaimers.
Rev. 2 — 3 March 2011
Level (dB)
0
−1
−2
−3
−4
−5
−6
reserved
Dual 11-bit ADC: CMOS or LVDS DDR digital outputs
Fig 22. Internal reference, 1 V (p-p) full-scale
Fig 24. Internal reference via SPI, 1 V (p-p) to 2 V (p-p)
O(cm)
full-scale
)
330 pF
330
pF
Full-scale (V (p-p))
2
1.78
1.59
1.42
1.26
1.12
1
x
SENSE
SENSE
VREF
VREF
ADC1112D125
REFERENCE
EQUIVALENT
SCHEMATIC
EQUIVALENT
REFERENCE
SCHEMATIC
Table
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© NXP B.V. 2011. All rights reserved.
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