LMH6618_0711 Datasheet, PDF (21/28 Pages) National Semiconductor (TI) – PowerWise® 130 MHz, 1.25 mA RRIO Operational Amplifiers

When the op amp and the ADC are using the same supply, it
is important that both devices are well bypassed. A 0.1 µF
ceramic capacitor and a 10 µF tantalum capacitor should be
located as close as possible to each supply pin. A sample
layout is shown in Figure 4. The 0.1 µF capacitors (C13 and
C6) and the 10 µF capacitors (C11 and C5) are located very
close to the supply pins of the LMH6618 and the
ADC121S101.
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FIGURE 4. LMH6618 and ADC121S101 Layout
SINGLE TO DIFFERENTIAL ADC DRIVER
Figure 5 shows the LMH6619 used to drive a differential ADC
with a single-ended input. The ADC121S625 is a fully differ-
ential 12-bit ADC. Table 2 shows the performance data of the
LMH6619 and the ADC121S625.
FIGURE 5. LMH6619 Driving an ADC121S625
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