ADC12081 Datasheet, PDF (4/16 Pages) National Semiconductor (TI) – 12-Bit, 5 MHz Self-Calibrating, Pipelined A/D Converter

Pin Descriptions and Equivalent Circuits #2 (Continued)
No.
Symbol
3
V_{IN com}
5
V_A
4, 6
AGND
13
V_D
9, 12
DGND
21
V_D I/O
20 DGND I/O
Equivalent Circuit
Description
Analog input common. Connect to a quiet point in
analog ground near the driving device. See section
1.2.
Positive analog supply pin. Connect to a clean,
quiet voltage source of +5V. V_A and V_D should have
a common supply and be separately bypassed with
a 5µF to 10µF capacitor and a 0.1µF chip capacitor.
The ground return for the analog supply. AGND and
DGND should be connected together close to the
ADC12081 package. See section 5.0.
Positive analog supply pin. Connect to a clean,
quiet voltage source of +5V. V_A and V_D should have
a common supply and be separately bypassed with
a 5µF to 10µF capacitor and a 0.1 µF chip
capacitor.
The ground return for the analog supply. AGND and
DGND should be connected together close to the
ADC12081 package. See section 5.0
The digital output driver supply pin. This pin can be
operated from a supply voltage of 3V to 5V, but the
voltage on this pin should never exceed the V_D
supply pin voltage.
The ground return for the output drivers. This pin
should be returned to a point in the digital ground
that is removed from the other ground pins of the
ADC12081.
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