STA5100

The STA5100 is a fully integrated power module designed to implement a BASH® amplifier when used in conjunction with STABP01 digital processor.

Notice that normally only one Digital Converter is needed to supply a stereo or multi-channel amplifier system, herefore most of the functions implemented in the STA5100 have summing outputs.

The signal STA5100s are biased by fixed negative and positive voltages referred to Ground. Instead the final stages of the output amplifiers are supplied by two external voltages that are following the audio signal . In this way the headroom for the output transistors is kept at minimum level to obtain a high efficiency power amplifier.

The Compressor STA5100s, one for each channel, performs a particular transfer behavior to avoid the dynamic restriction that an adaptive system like this requires. To have a high flexibility the attack / release time and the threshold levels are externally programmable. The tracking signal for the external digital converter is generated from the Absolute Value block that rectifies the audio signal present at the compressor output. The outputs of these STA5100s are decoupled by a diode to permit an easy sum of this signal for the multichannel application. The output power bridges have a dedicated input pin to perform an AC decoupling to cancel the compressor output DC offset. The gain of the stage is equal to 4 (+12dB). A sophisticated circuit performs the output transistor power detector that , with the digital converter, reduces the power supply voltage . Moreover, a maximum current output limiting and the over temperature sensor have been added to protect the circuit itself. The external voltage applied to the STBY/MUTE pin forces the two amplifiers in the proper condition to guarantee a silent turnon and turn-off.