TDA5931 Integrated Circuit

TDA5931 Integrated Circuit

The TDA5931 is a monolithic integrated circuit originally manufactured by Philips (now NXP), designed primarily as an interface for TV tuners and PLL (Phase-Locked Loop) control systems, often used in combination with microcontrollers for frequency tuning in televisions and satellite receivers.

Here are the main technical specifications and features:

1. Main Function

• Programmable Frequency Divider (Prescaler): Designed to divide high-frequency signals coming from the tuner, allowing the microprocessor to process and lock the desired frequency via a control bus.

2. Electrical Characteristics (Typical)

• Supply Voltage ($V_{CC}$): Typically 5V (standard for control logic).
• Input Frequency Range (RF Input): Generally ranges up to 1 GHz (specific to VHF/UHF in traditional TV systems).
• Input Sensitivity: High sensitivity to accept weak RF signals from the local oscillator of the tuner (typically in the order of tens of millivolts).
• Division Ratio: Programmable via software (using an I²C bus or similar serial interfaces depending on the exact revision).

3. Interface and Control

• Communication Bus: I²C compatible serial interface for programming the divider and managing auxiliary outputs.
• Switching Outputs (Band Switches): Usually features dedicated outputs (open-collector I/O ports) to switch tuner bands (e.g., Band I, Band III, UHF).

4. Package / Encapsulation

• Encapsulation: Commonly available in DIP-18 (Dual In-line Package) or SO-16/SO-20 packages depending on the SMD version.

5. Historical Applications

• Analogue and hybrid CRT televisions.
• VCRs (Videocassette Recorders).
• Vintage terrestrial/satellite radio and TV receivers.

Note: As this is a rather dated component (it was widely used in the 1990s), availability on the current market is limited to old stock.