AD569

REV. A

–9–

Figure 13. Low-Cost

±5 V Tracking Reference

a. Bandwidth

b. Phase Shift

Figure 14. Full Power Multiplying Performance

a. Time Domain

b. Frequency Domain

Figure 15. Multiplying Mode Performance (Input Code

MULTIPLYING PERFORMANCE

Figure 14 illustrates the gain and phase characteristics of the

AD569 when operated in the multiplying mode. Full-power

bandwidth is shown in Figure 14a and the corresponding phase

shift is shown in Figure 14b. Performance is plotted for both a

resents worst-case conditions because it places the buffer taps at

the midpoints of both dividers. Figure 15 illustrates the

AD569’s ability to resolve 16-bits (where 1 LSB is 96 dB below

full scale) while keeping the noise floor below –130 dB with an

ac reference of 1 V rms at 200 Hz.

Multiplying feedthrough is due to capacitive coupling between

the reference inputs and the output. As shown in Figure 16,