4046 IC CMOS Phase-Locked Loop (PLL) with VCO
The CD4046BE is a versatile CMOS integrated circuit that combines a Phase-Locked Loop (PLL) system with a Voltage-Controlled Oscillator (VCO) and two independent phase comparators. It plays a key role in frequency synthesis, demodulation, clock recovery, and tone decoding. Its design supports both analog and digital applications, making it a valuable component for engineers and hobbyists alike.
This IC contains two phase comparators: one exclusive OR logic-based (PC1) and the other edge-triggered SR flip-flop type (PC2), giving designers flexibility depending on the application’s precision and noise immunity requirements. The VCO can operate over a wide range of frequencies depending on the external resistor and capacitor network connected to the appropriate pins. The chip ensures stable lock-in and fast response, which makes it ideal for applications like FM demodulation, signal synchronization, and motor speed control.
Key Features
Includes VCO and two phase comparators
Operating voltage range: 3V to 15V
Low power CMOS technology
High noise immunity
Wide frequency range (up to several MHz)
Adjustable VCO range with external components
Compatible with TTL and CMOS logic levels
Available in 16-pin DIP package
Pin Configuration (16-Pin DIP Package)
| Pin No | Symbol | Description |
|---|---|---|
| 1 | COMP IN | Input to phase comparator I |
| 2 | SIG IN | Signal input for both comparators |
| 3 | PC1 OUT | Output of phase comparator I |
| 4 | GND | Ground |
| 5 | C1 | Capacitor connection for VCO |
| 6 | R1 | Resistor connection for VCO (to GND) |
| 7 | R2 | Resistor connection for VCO (to VDD) |
| 8 | VCO OUT | Output of Voltage-Controlled Oscillator |
| 9 | INH | VCO inhibit input ‘ |
| 10 | VSS | Negative supply (Ground in single supply) |
| 11 | ZENER | Zener diode reference (optional) |
| 12 | VDD | Positive supply voltage |
| 13 | PC2 OUT | Output of phase comparator II |
| 14 | PC2 IN | Input to phase comparator II |
| 15 | DEM OUT | Demodulator output |
| 16 | LF IN | Loop filter input |
Applications
Frequency demodulation (FM/FSK)
Clock/data recovery circuits
Frequency multiplication/division
Signal synchronization
Tone decoders
Phase/frequency detectors
Motor speed control systems
