ADC14L040 Datasheet, PDF (20/23 Pages) National Semiconductor (TI) – 14-Bit, 40 MSPS, 235 mW A/D Converter

Applications Information (Continued)
FIGURE 4. Application Circuit using Transformer Drive Circuit
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FIGURE 5. Differential Drive Circuit of Figure 4
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4.0 POWER SUPPLY CONSIDERATIONS
The power supply pins should be bypassed with a 10 µF
capacitor and with a 0.1 µF ceramic chip capacitor close to
each power pin. Leadless chip capacitors are preferred be-
cause they have low series inductance.
As is the case with all high-speed converters, the
ADC14L040 is sensitive to power supply noise. Accordingly,
the noise on the analog supply pin should be kept below 100
mV_P-P.
No pin should ever have a voltage on it that is in excess of
the supply voltages, not even on a transient basis. Be espe-
cially careful of this during power turn on and turn off.
The V_DR pin provides power for the output drivers and may
be operated from a supply in the range of 2.4V to V_D. This
can simplify interfacing to lower voltage devices and sys-
tems. Note, however, that t_OD increases with reduced V_DR.
DO NOT operate the V_DR pin at a voltage higher than V_D.
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