DESCRIPTION

The HEF4750V frequency synthesizer is one of a pair of LOCMOS devices, primarily intended for use in high-performance frequency synthesizers, e.g. in all communication, instrumentation, television and broadcast applications. A combination of analogue and digital techniques results in an integrated circuit that enables high performance. The complementary device is the universal divider type HEF4751V.

Together with a standard prescaler, the two LOCMOS integrated circuits offer low-cost single loop synthesizers with full professional performance. Salient features offered (in combination with HEF4751V) are:

• Wide choice of reference frequency using a single crystal.

• High-performance phase comparator ― low phase

noise ― low spurii.

• System operation to > 1 GHz.

• Typical 15 MHz input at 10 V.

• Flexible programming:

frequency offsets

ROM compatible

fractional channel capability.

• Programme range 61⁄2 decades, including up to

3 decades of prescaler control.

• Division range extension by cascading.

• Built-in phase modulator.

• Fast lock feature.

• Out-of-lock indication.

• Low power dissipation and high noise immunity.

APPLICATION INFORMATION

Some examples of applications for the HEF4750V in combination with the HEF4751V are:

• VHF/UHF mobile radios.

• HF s.s.b. transceivers.

• Airborne and marine communications and navaids.

• Broadcast transmitters.

• High quality radio and television receivers.

• High performance citizens band equipment.

• Signal generators.