adc1112d125 NXP Semiconductors, adc1112d125 Datasheet - Page 20

• 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
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
Internal via SPI
(Figure
External
(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 — 3 March 2011
Table
12.
REFERENCE
Dual 11-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
ADC CORE
ADC1112D125
[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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