Freescale公司的 SGTL5000是集成了耳機(jī)放大器的低功耗立體聲CODEC,具有線輸入,麥克風(fēng)輸入,線輸出,耳機(jī)輸出和數(shù)字I/O.模擬輸入的ADC的SNR為 85 dB,線輸出的SNR為100 dB,器件的工作電壓為1.62 - 3.6V,主要用在手持媒體播放器(PMP),GPS單元和智能手機(jī).本文介紹了SGTL5000主要特性,框圖, 應(yīng)用框圖,幾種典型應(yīng)用電路以及評估板KITSGTL5000EVBE主要特性,方框圖和電路圖.
The SGTL5000 is a Low Power Stereo Codec with Headphone Amp from Freescale, and is designed to provide a complete audio solution for portable products needing line-in, mic-in, line-out, headphone-out, and digital I/O. Deriving it’s architecture from best in class, Freescale integrated products that are currently on the market. The SGTL5000 is able to achieve ultra low power with very high performance and functionality, all in one of the smallest footprints available. Target markets include portable media players, GPS units, and smart phones.
Features such as capless headphone design and an internal PLL, help lower overall system cost.

SGTL5000主要特性:
Analog Inputs
• Stereo Line In - Support for external analog input
• Stereo Line In - Codec bypass for low power
• MIC bias provided (5.0 x 5.0 mm QFN, 3.0 x 3.0 mm QFN TA2)
• Programmable MIC gain
• ADC - 85 dB SNR (-60 dB input) and -73 dB THD+N (VDDA = 1.8 V)Analog Outputs
• HP Output - Capless design
• HP Output - 45 mW max into 16 ohm load @ 3.3 V
• HP Output - 100 dB SNR (-60 dB input) and -80 dB THD+N (VDDA = 1.8 V, 16 ohm load, DAC to headphone)
• Line Out - 100 dB SNR (-60 dB input) and -85 dB THD+N (VDDIO = 3.3 V) Digital I/O
• I2S port to allow routing to Application Processor Integrated Digital Processing
• Freescale Surround, Freescale Bass, tone control/ parametric equalizer/graphic equalizer Clocking/Control
• PLL allows input of an 8.0 MHz to 27 MHz system clock - Standard audio clocks are derived from PLL
Power Supplies
• Designed to operate from 1.62 to 3.6 volts

圖1.SGTL5000簡化框圖

圖2.SGTL5000簡化應(yīng)用框圖

圖3.20 QFN封裝的SGTL5000 典型應(yīng)用電路

圖4.20 QFN封裝的SGTL5000 最低功耗應(yīng)用電路

圖5.32 QFN封裝的SGTL5000 最低功耗應(yīng)用電路

圖6.32 QFN封裝的SGTL5000 最低功耗應(yīng)用電路(2)

SGTL5000評估板KITSGTL5000EVBE
The KITSGTL5000EVBE Evaluation board supports the SGTL5000, which is a Low Power Stereo Codec with Headphone Amp from Freescale, and is designed to provide a complete audio solution for portable products needing line-in, mic-in, line-out, headphone-out, and digital I/O.

評估板KITSGTL5000EVBE主要特性:
SGTL5000 Audio Codec
LINEIN RCA analog input jack
LINEOUT RCA analog output jack
Selectable mini-jack or onboard microphone input
Stereo headphone mini-jack analog output, with optional capless design circuitry
Two-row headers for buffered I2S digital input/output
Support for onboard or external MCLK source
USB to I2C/SPI communication port
5V input voltage through either internal LDO regulators, or external individual supplies

圖7.評估板KITSGTL5000EVBE外形圖

圖8.評估板KITSGTL5000EVBE框圖

圖9.評估板KITSGTL5000EVBE電路圖(1)

圖10.評估板KITSGTL5000EVBE電路圖(2)

圖11.評估板KITSGTL5000EVBE電路圖(3)

圖12.評估板KITSGTL5000EVBE電路圖(4)

圖13.評估板KITSGTL5000EVBE電路圖(5)

圖14.評估板KITSGTL5000EVBE電路圖(6)

圖15.評估板KITSGTL5000EVBE電路圖(7)