Rainbow Electronics ADC12D040 - Manual (Page 5)

Pin Descriptions and Equivalent Circuits
(Continued)
Pin No. Symbol Equivalent Circuit Description
24–29
34–39
DA0–DA11
Digital data output pins that make up the 12-bit conversion
results of their respective converters. DA0 and DB0 are the
LSBs, while DA11 and DB11 are the MSBs of the output
word. Output levels are TTL/CMOS compatible.
42–47
52–57
DB0–DB11
ANALOG POWER
9, 18, 19,
62, 63
V
A
Positive analog supply pins. These pins should be connected
to a quiet +5V source and bypassed to AGND with 0.1 µF
monolithic capacitors located within 1 cm of these power pins,
and with a 10 µF capacitor.
3, 8, 10,
17, 20, 61,
64
AGND The ground return for the analog supply.
DIGITAL POWER
33, 48 V
D
Positive digital supply pin. This pin should be connected to
the same quiet +5V source as is V
A
and be bypassed to
DGND with a 0.1 µF monolithic capacitor located within 1 cm
of the power pin and with a 10 µF capacitor.
32, 49 DGND The ground return for the digital supply.
30, 51 V
DR
Positive digital supply pins for the ADC12D040’s output
drivers. These pins should be connected to a voltage source
of +2.4V to +5V and bypassed to DR GND with a 0.1 µF
monolithic capacitor. If the supply for these pins are different
from the supply used for V
A
and V
D
, they should also be
bypassed with a 10 µF tantalum capacitor. V
DR
should never
exceed the voltage on V
D
. All bypass capacitors should be
located within 1 cm of the supply pin.
23, 31, 40,
50, 58
DR GND
The ground return for the digital supply for the ADC12D040’s
output drivers. These pins should be connected to the system
digital ground, but not be connected in close proximity to the
ADC12D040’s DGND or AGND pins. See Section 5 (Layout
and Grounding) for more details.
ADC12D040
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