The AD9901 is a digital phase/frequency discriminator capable of directly comparing phase/frequency inputs up to 200 MHz. Processing in a high speed trench-oxide isolated process, combined with an innovative design, gives the AD9901 a linear detection range, free of indeterminate phase detection zones common to other digital designs.
With a single +5 V supply, the AD9901 can be configured to operate with TTL or CMOS logic levels; it can also operate with ECL inputs when operated with a -5.2 V supply. The open-collector outputs allow the output swing to be matched to post-filtering input requirements. A simple current setting resistor controls the output stage current range, permitting a reduction in power when operated at lower frequencies.
A major feature of the AD9901 is its ability to compare phase/frequency inputs at standard IF frequencies without prescalers. Excessive phase uncertainty which is common with standard PLL configurations is also eliminated. The AD9901 provides the locking speed of traditional phase/frequency discriminators, with the phase stability of analog mixers.
The AD9901 is available as a commercial temperature range device, 0°C to +70°C, and as a military temperature device, -55°C to +125°C. The commercial versions are packaged in a 14-pin ceramic DIP and a 20-pin PLCC.
The AD9901 Phase/Frequency Discriminator is available in versions compliant with MIL-STD-883. Refer to the Analog Devices Military Products Databook or current AD9901/883B data sheet for specifications.
