adc1213d125hn/c1 NXP Semiconductors, adc1213d125hn/c1 Datasheet - Page 17

• Manufacturer Part Number: adc1213d125hn/c1
• Description: Dual 12-bit Adc; 65 Msps, 80 Msps, 105 Msps Or 125 Msps
• Manufacturer: NXP Semiconductors

NXP Semiconductors
ADC1213D_SER_5
Preliminary data sheet
Fig 11. Internal reference, 2 V (p-p) full-scale
Fig 13. External reference, 1 V (p-p) to 2 V (p-p)
full-scale
14.2.2 Reference gain control
14.2.3 Common-mode output voltage (V
V
330 pF
SENSE
VREF
VDDA
0.1 μF
SENSE
The reference gain is programmable between 0 dB to −6 dB in steps of 1 dB via the SPI
(see
and 1 V (p-p), as shown in
Table 11.
An 0.1 μF filter capacitor should be connected between on the one hand the pins VCMA
and VCMB and on the other hand ground to ensure a low-noise common-mode output
voltage. When AC-coupled, these pins can be used to set the common-mode reference
for the analog inputs, for instance via a transformer middle point.
VREF
INTREF[2:0]
000
001
010
011
100
101
110
111
EQUIVALENT
REFERENCE
Table
SCHEMATIC
REFERENCE
EQUIVALENT
SCHEMATIC
Reference SPI gain control
21). The corresponding full scale input voltage range varies between 2 V (p-p)
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All information provided in this document is subject to legal disclaimers.
Rev. 05 — 23 April 2010
Table
11:
Fig 12. Internal reference, 1 V (p-p) full-scale
Fig 14. Internal reference via SPI, 1 V (p-p) to 2 V (p-p)
Level
0 dB
−1 dB
−2 dB
−3 dB
−4 dB
−5 dB
−6 dB
not used
I(cm)
full-scale
)
330 pF
330
pF
ADC1213D series
SENSE
SENSE
VREF
VREF
REFERENCE
EQUIVALENT
Full Scale, V (p-p)
2
1.78
1.59
1.42
1.26
1.12
1
x
SCHEMATIC
EQUIVALENT
REFERENCE
SCHEMATIC
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ADC1213D series
© NXP B.V. 2010. All rights reserved.
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