TA7371AF

TOSHIBA Bipolar Linear Integrated Circuit Silicon Monolithic TA7371AF FM Front−End (1.5V USE) TA7371AF The TA7371AF is an FM front end IC designed for low voltage operation (1.5V), which is suitable for stereo headphone radio or radio cassette. This IC contains RF amplifier, MIX, local oscillator and varactor diode for AFC. It simplifies the design of front end circuit. Features · Clamping diode for mixer output. · Varactor diode for AFC. · Local OSC. stop voltage: VCC = 0.85V (typ.) · Low quiescent current ICC = 1.8mA (typ.) (VCC = 1.5V, Ta = 25°C) · Low noise. · Very few external parts. · Operating supply voltage range.: VCC = 0.95~5V (Ta = 25°C) Weight: 0.08g (typ.) Block Diagram 1 2002-10-30 Explanation Of Inner Circuit And Functions (1) RF block The radio signal is applied to RF INPUT passed through the ANT and BPF. This RF block is composed of the common emitter amplifier. The output is designed to be the cascade connection, because of high sensitivity characteristic, and excellent spurious radiation. (Fig.1) (2) MIX block The MIX block is composed of the emitter coupled pair amplifier. (Fig.2) (3) OSC block OSC block is composed of the colpitts oscillation circuit. The capacitors C1 and C2 are built in this IC. TA7371AF (Fig.1) (Fig.2) (Fig.3) 2 2002-10-30 Maximum Ratings (Ta = 25°C) Characteristic Symbol Rating Unit Supply voltage Power dissipation Operating temperature Storage temperature VCC PD (Note) Topr Tstg 5 240 -25~75 -55~150 V mW °C °C (Not...