INTERFACES WITH DUAL–MODULUS PRESCALERS

Legacy Device: Motorola MC145106

The ML145106 is a phase–locked loop (PLL) frequency synthesizer constructed in CMOS on a single monolithic structure. This synthesizer finds applications in such areas as AM radio, shortwave, amateur radio, CB and FM transceivers. The device contains an oscillator/amplifier, a 210 or 211 divider chain for the oscillator signal, a programmable divider chain for the input signal, and a phase detector. The ML145106 has circuitry for a 10.24 MHz oscillator or may operate with an external signal. The circuit provides a 5.12 MHz output signal, which can be used for frequency tripling. A 29 programmable divider divides the input signal frequency for channel selection. The inputs to the programmable divider are standard ground–to–supply binary signals. Pull–down resistors on these inputs normally set these inputs to ground enabling these programmable inputs to be controlled from a mechanical switch or electronic circuitry.

• Single Power Supply

• Wide Supply Range: 4.5 to 12 V

• Provision for 10.24 MHz Crystal Oscillator

• 5.12 MHz Output

• Programmable Division Binary Input Selects up to 29

• On–Chip Pull–Down Resistors on Programmable Divider Inputs

• Selectable Reference Divider, 210 or 211 (Including ÷ 2)

• Three–State Phase Detector

• See Application Note AN535 and Article Reprint AR254

• Chip Complexity: 880 FETs or 220 Equivalent Gates