Stereo Digital Audio CODEC Solution Using SSM2603
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ADI's SSM2603 is a low-power, high-quality stereo digital audio CODEC for portable digital audio applications with a set of stereo programmable gain amplifier (PGA) line inputs and a monaural microphone input. It has two 24-bit analog-to-digital converter (ADC) channels and two 24-bit digital-to-analog converter (DAC) channels. The SSM2603 can be used as a master or slave. It supports multiple master clock frequencies, including 12MHz or 24MHz for USB devices; standard 256fS or 384fS base rates such as 12.288MHz and 24.576MHz; and many common audio sample rates such as 96kHz, 88.2kHz, 48kHz, 44.1 kHz, 32 kHz, 24 kHz, 22.05 kHz, 16 kHz, 12 kHz, 11.025 kHz, and 8 kHz. The SSM2603 operates from a minimum of 1.8V in the case of analog circuits and operates from a supply voltage as low as 1.5V in the case of digital circuits. The SSM2603 software programmable stereo output option offers users a variety of application possibilities. Its volume control provides extensive gain control of the audio signal. The industrial application temperature range of the SSM2603 is -40°C to +85°C. It is available in a 28-pin, 5mm x 5mm leadframe chip scale package (LFCSP). 
Figure 1 SSM2603 functional block diagram 
Figure 2 SSM2603 typical application circuit diagram
Main features of SSM2603
• Stereo, 24-bit analog-to-digital and digital-to-analog converters
• DAC SNR: 100dB (A-weighted), THD: -80dB at 48kHz, 3.3V
• ADC SNR: 90dB (A-weighted), THD: -80dB at 48kHz, 3.3V
• High efficiency headphone amplifier
• Stereo line input and monaural microphone input
• Low power
- 7mW stereo playback (1.8V/1.5V power supply)
- 14mW recording and playback (1.8V/1.5V power supply)
• Low power supply
- Analog: 1.8 V to 3.6 V
- Digital core: 1.5 V to 3.6 V
- Digital I/O: 1.8 V to 3.6 V
• 256/384 oversampling rate in normal mode; 250/272 oversampling rate in USB mode
• Audio sampling rate: 8kHz, 11.025kHz, 12kHz, 16kHz, 22.05kHz, 24kHz, 32kHz, 44.1kHz, 48kHz, 88.2kHz and 96kHz
• 28-pin, 5mm x 5mm LFCSP (QFN) package 
Figure 3 SSM2603 evaluation board top outline drawing
SSM2603 application
• Mobile phone
• MP3 player
• Portable game console
• Portable electronic devices
• brain game
SSM2603 Evaluation Board
The SSM2603 evaluation board contains a complete application circuit for the SSM2603 that is connected to the host PC via USB. As a link to power, digital audio data and control/status data, it becomes a plug-and-play audio device that can communicate via software under the Microsoft Windows operating system. The evaluation version uses a universal 2.54mm pitch-pitch connector that connects to an external DSP/MCU for digital audio signals.
Main features of the SSM2603 evaluation board
• Connect to the host PC via USB
• Externally connected to the DSP/MCU for digital audio signals (via universal 2.54mm pin, pitch connector)
• 4 audio jacks: stereo input line, mono microphone input, stereo line out, and stereo headphone output
• Multiple test points on the evaluation board for monitoring signals
• Master/slave mode selection
To satisfy high voltage application demands, allowing apm DC Source System to cover a voltage range from 0V to 800V,the switching power supply has low load regulation, which ensure stable output when the load is changing constantly. The smps power supply supports standard SCPI communication protocol, which is convenient for user`s secondary development.
Some features as below:
- With accurate voltage and current measurement capability.
- Coded Knob, multifunctional keyboard.
- Standard RS232/RS485/USB/LAN communication interfaces, GPIB is optional.
- Remote sensing line voltage drop compensation.
- Equips with LIST waveform editing function.
- Use the Standard Commands for Programmable Instrumentation(SCPI) communication protocol.
- Have obtained CE certification.
800V DC Source System,Adjustable Voltage Power Supply,Dc Voltage Source,800V Dc Power Source
APM Technologies Ltd , https://www.apmpowersupply.com