adc1212d NXP Semiconductors, adc1212d Datasheet - Page 21

• Manufacturer Part Number: adc1212d
• Description: Adc1212d Series Dual 12-bit Adc; 65 Msps, 80 Msps, 105 Msps Or 125 Msps; Cmos Or Lvds Ddr Digital Outputs
• Manufacturer: NXP Semiconductors

NXP Semiconductors
ADC1212D_SER
Product data sheet
If bit INTREF_EN is set to logic 0, the reference voltage is determined either internally or
externally as detailed in
Table 12.
[1]
Figure 21
required reference voltage source.
Selection
Internal
(Figure
Internal
(Figure
External
(Figure
Internal via SPI
(Figure
Fig 20. Reference equivalent schematic
SENSE
The voltage on pin VREF is doubled internally to generate the internal reference voltage.
VREF
21)
22)
23)
24)
to
Reference selection
Figure 24
All information provided in this document is subject to legal disclaimers.
SPI bit
INTREF_EN
0
0
0
1
BUFFER
SELECTION
LOGIC
illustrate how to connect the SENSE and VREF pins to select the
Rev. 2 — 4 March 2011
Table
12.
REFERENCE
Dual 12-bit ADC: CMOS or LVDS DDR digital outputs
SENSE pin
AGND
pin VREF connected to pin SENSE and
via a 330 pF capacitor to AGND
V
pin VREF connected to pin SENSE and
via 330 pF capacitor to AGND
DDA
AMP
EXT_ref
EXT_ref
REFERENCE
BANDGAP
330 pF capacitor to
VREF pin
AGND
external voltage between
0.5 V and 1 V
ADC1212D series
ADC CORE
[1]
REFAB/
REFBB
REFAT/
REFBT
© NXP B.V. 2011. All rights reserved.
Full-scale
(V (p-p))
2 V
1 V
1 V to 2 V
1 V to 2 V
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