This post explains for the Digital Audio Amplifier.
The Part Number is NS4358.
The function of this IC is 2.1-channel Surround Sound Digital Audio Amplifier.
The package is TQFN4×4-28, SOP-28.
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NS4358 is an ultra low EMI, no filter, 5W + 3W × 2 high efficiency 2.1 channel + 3D surround stereo Class D audio Power amplifier. The NS4358 utilizes advanced technology to significantly reduce EMI interference over a full bandwidth range, minimizing damage to other components influences. Its output without the need for filter PWM modulation structure and feedback resistor built-in way to reduce the external components, the 2.1 channel function, 3D ring The surround sound function and bandpass filter are integrated on a single chip with minimal external components, the largest savings in PCB area and system cost.
NS4358 built-in overcurrent protection, overheating protection and undervoltage protection, effectively protect the chip in the abnormal working conditions are not damaged. and the use of spread spectrum technology to fully optimize the new circuit design, up to 90% more efficient for low voltage, high power output audio system.[…]
The Part Number is STi7141. The Package is PBGA 580 + 100 balls, 35 x 35 mm Type.
The function of this semiconductor is HD decoder for interactive digital cable set-top box .
The STi7141 is a highly integrated SoC (systemon-chip) designed to meet the demanding needs of the interactive cable set top box market place. The STi7141 integrates all the major system functions into a single device, and provides world leading, multi-layer, advanced security technologies to protect valuable video and audio assets.
The STi7141 is a low-cost, networkable, HDTV set-top box device, with an embeded
DOCSIS cable modem capable of providing DSG (DOCSIS set-top gateway), interactive
multimedia and internet access for the digital cable market.
1. Three integrated cable receiver / demodulators
2. DOCSIS/EuroDOCSIS 2.0 cable modem with support for DOCSIS 3.0 down-stream channelbonding
3. SCTE-55 part 1 and 2 physical layer support for CableCARDTM
4. Dual Core architecture providing more than 1600 DMIPS of processing performance