Description

The TDA5744TS is an Integrated Circuit (IC) chip belonging to the 2-band mixers/oscillators category, designed for VHF/UHF and hyperband tuners. It comprises two double balanced mixers and two oscillators, one for the VHF band and the other for the UHF band, along with an IF amplifier. The TV bands can be covered by splitting the VHF band into two sub-bands using a switchable inductor. The IC features a band switch pin and two pins enabling IF filtering for improved signal handling, along with a low output impedance IF amplifier to drive the SAW filter directly. It has a small form factor, low power, and low radiation, making it suitable for use in Full Scale Tuners (FST).

Specifications and features

• 2-band mixers/oscillators for hyperband tuners
• Balanced mixer with a common emitter input for VHF (single input)
• Balanced mixer with a common base input for UHF (double input)
• 4-pin common emitter oscillator for VHF
• 4-pin common emitter oscillator for UHF
• Electronic band switch
• IF amplifier with a low output impedance to drive the SAW filter directly (≈2 kΩ load)
• Pin compatible single-chip synthesizer mixer/oscillator for Full Scale Tuners (FST) are available: TDA6404, TDA6405 and TDA6405A

Application Scenarios

Hyperband tuners for Europe using a 2-band mixer/oscillator in a switched concept.

Comparison

• Two double balanced mixers and two oscillators included, making it suitable for VHF/UHF and hyperband tuners
• Electronic band switch for ease of use
• IF amplifier with a low output impedance to drive the SAW filter directly, resulting in improved signal handling
• Pin compatible with other IC chips for Full Scale Tuners (FST)
• Small form factor, low power consumption, and low radiation.

• The IC is designed specifically for hyperband tuners and may not be suitable for other applications
• The device may not be compatible with existing circuit designs
• The device's features may not be fully utilized if the circuit design is suboptimal