Features: 1.1 Easy application
` Voltage output 1.5 V (RMS)
` Operational amplifiers and cascaded 4-stage digital FIR filter integrated
` Master and slave mode clock system with selectable system clock (fsys) 256fs or 384fs
` I2S-bus serial input format or Japanese 16, 18 or 20 bits serial input mode
` All features are accessible under remote control
` Simple 3-line serial microcontroller command interface
` Power-on reset
` 28 lead small outline package.
1.2 High performance
` Superior signal-to-noise ratio
` Low total harmonic distortion
` Wide dynamic range
` No zero crossing distortion
` Continuous calibration digital-to-analog conversion combined with noise shaping techniques
` Second-order noise shaper
` 128 times oversampling in normal-speed mode
` 64 times oversampling in double-speed mode.
1.3 Digital sound processing features
1.3.1 VOLUME CONTROL FEATURES
` Smoothed transitions before and after digital mute (soft mute)
` Fade function: duration-programmable (6 ms to 22.4 s at 44.1 kHz) digital volume control (attenuation as well as gain): +6 dB to -90 dB in steps of 0.375 dB with automatic soft mute
` Digital balance: 0 dB to -22.5 dB in steps of -1.5 dB (maximum overall attenuation combined with volume control: -90 dB)
1.3.2 SOUND PROCESSING FEATURES
` Digital de-emphasis filter for three sample rates (32 kHz, 44.1 kHz or 48 kHz)
` Digital treble: -10.5 dB to +12 dB at 20 kHz; 16 steps spaced at 1.5 dB
` Digital bass: -9 dB to +13.5 dB at 20 Hz; 16 steps spaced at 1.5 dB
` Distortion-free digital dynamic bass boost: 0 dB to +37 dB at 10 Hz; 15 steps spaced at 2 dB
` Can be used for loudness or dynamic digital bass boost
` Double-speed mode (e.g. for high-speed dubbing)
` Pseudo double-speed mode (for power saving application)
` Digital speaker system mode including digital crossover filter.
1.3.3 SOUND MONITOR FEATURES
` Spectrum analyzer for seven different frequency ranges
` Digital silence detection. Level (-48 dB to dB, in steps of 3 dB) and duration (200 ms to 3.2 s, in steps of 200 ms at 44.1 kHz) programmable. Output via versatile pins.
` Peak level detection and readout to microcontroller (dB linear, 0 dB to -90 dB in steps of 1.5 dB)
` Digital overload detection. Level-programmable (dB linear, -1.5 dB to -46.5 dB, in steps of 3 dB). Output via versatile pins.
` Digital spectrum analyzer by combination of peak detection and 7-band selective filter
` Optional combination spectrum analyzer and overload detection for frequency-dependent overload detection.Pinout
DescriptionThe TDA1546T is the first Bitstream Continuous Calibration digital-to-analog converter (BCC-DAC) to feature unique signal processing functions. In addition to the basic functions of digital filtering and digital-to-analog conversion, it offers such advanced digital signal processing functions as volume control, tone control, bass boost, peak or spectrum analyzer readout and many more convenient functions. The digital processing features are of high sound quality due to the wide dynamic range of the bitstream conversion technique.
The TDA1546T accepts I2S-bus data input formats with word lengths of up to 20 bits and various Japanese serial data input formats with word lengths of 16, 18 and 20 bits. The circuit can operate as a master or slave with different system clocks (256fs or 384fs) and is therefore, eminently suitable for use in various applications such as DCC, CD, DAT and MD.
The range of TDA1546Ts is further extended by an incorporated Digital Speaker System mode (DSS) with digital crossover filter.
Four cascaded FIR filters and a sample-and-hold function increase the oversampling rate from 1fs to 96fs (384fs system clock) or 128fs (256fs system clock). A second-order noise shaper converts this oversampled data to a bitstream for the 5-bit DACs.
The DACs are of the continuous calibration type and incorporate a special data coding technique, which contributes to a high signal-to-noise ratio and dynamic range.
On-board amplifiers convert the output current to a voltage signal capable of driving a line output. Externally connected capacitors perform the required first-order filtering. Additional post filtering is not required.
TDA1546T Data Sheet
