ADC10040CIMT National Semiconductor Corporation, ADC10040CIMT Datasheet - Page 17

• Manufacturer Part Number: ADC10040CIMT
• Description: ADC10040 - 10-Bit, 40 Msps, 3V, 55.5 MW A/D Converter, Package: Tssop, Pin Nb=28
• Manufacturer: National Semiconductor Corporation

Applications Information
must charge for each conversion, the more instantaneous
digital current flows through V
charging current spikes can cause on-chip ground noise and
couple into the analog circuitry, degrading dynamic perfor-
mance. Adequate bypassing, limiting output capacitance and
careful attention to the ground plane will reduce this prob-
lem. Additionally, bus capacitance beyond the specified
10 pF/pin will cause t
properly latch the ADC output data. The result could be an
apparent reduction in dynamic performance. To minimize
noise due to output switching, minimize the load currents at
OD
FIGURE 6. A Simple Application Using a Single Ended Driving Source
to increase, making it difficult to
FIGURE 5. A Simple Application Using a Differential Driving Source
DDIO
and V
SSIO
(Continued)
. These large
17
the digital outputs. This can be done by connecting buffers
between the ADC outputs and any other circuitry. Only one
driven input should be ADC pins, will isolate the outputs from
trace and other circuit capacitances and limit the output
currents, which could otherwise result in performance deg-
radation.
1.8 APPLICATION SCHEMATICS
The following figures show simple examples of using the
ADC10040. Figure 5 shows a typical differentially driven
input. Figure 6 shows a single ended application circuit.
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