Application Notes

AN-101A (119 KB) - "Driving the QM Series Quadrature Modulators"
Discusses common methods of driving the QM series baseband I/Q inputs. Active and passive interface circuits are presented for driving the QM series Quadrature Modulators with single-ended I and Q signal sources. An active driver circuit for interfacing to modern differential D/A converters is also included.

AN-102A (115 KB) - "Interface Circuits for the QD Series Quadrature Demodulators"
This note provides active and passive circuit ideas that interface the QD series baseband I/Q outputs to single-ended loads. A fully-differential active circuit is also presented for interfacing the QD series to modern A/D converters. The amplifier circuit has adjustable gain and lowpass cutoff frequency for anti-alias filtering.