STMicroelectronics announced the availability of its model TDA7701 single-chip FM tuner for portable entertainment and computing equipment. The tuner works with FM radio broadcast standards worldwide, and is programmed and controlled via its built-in I2C and SPI buses.

The device operates from a low-voltage, low-current source: 2.4 to 3.2V dc at 12mA. The chip comes in a 5 by 5mm TFBGA40 chip-scale package having two rows of 300-micron diameter balls on 500-micron centers. In addition, the chip cuts the external component count, and therefore cost, by eschewing IF (Intermediate Frequency) filters, ceramic capacitors, and varicaps. These advantages are achieved by the chip’s low-frequency 425kHz IF stage sporting built-in channel selection filters and a VCO (voltage controlled oscillator) with built-in varicaps.

Key function blocks integrated into the chip include a phase-locked loop with automatic search function, low-noise amplifier with image rejection mixer, and FM demodulator with adjustment-free decoder. A subsequent version being planned will include an RDS (radio data system) decoder with group and block synchronization.

Among performance specifications of the single-chip tuner are a 60dB maximum S/N (signal-to-noise) ratio, 3dB/microvolt usable sensitivity at 30dB S/N ratio; 40dB selectivity at ±300kHz, 30dB stereo separation, and 0.5 percent THD (total harmonic distortion). http://www.st.com/stonline/press/news/year2005/p1564hbig1.jpg

The TDA7701 single-chip FM tuner sells for $2.50 each in quantities of 1,000, and is available now in production volumes quantities. An evaluation kit, including a hardware platform and software with API (application programming interface) functions and a graphics user interface for demonstration, development, and validation is also available.