24-Bit 2ch ADC & 2ch DAC with Auto HPF, ALC/Eq and MIC/HP/SPK-Amp
The AK4951 is a low power 24-bit stereo CODEC with a microphone, headphone and speaker amplifiers. The AK4951 supports sampling frequency from 8kHz to 48kHz. It is suitable for a wide range of application from speech signal processing for narrowband, wideband and super wideband to sound signal processing for audio band. The input circuits include a microphone amplifier, an automatic wind noise reduction filter of the proprietary algorithms and a high performance digital ALC (automatic level control) circuit, therefore the AK4951 can record with high-quality sound regardless of whether indoors or outdoors. In addition, the output circuits include a cap-less headphone amplifier with a negative voltage generated by charge pump circuit and a speaker amplifier with 1W output power. It is suitable for various products as well as portable applications with recording/playback function.
The AK4951 are available in a small 32-pin QFN (4mm x 4mm, 0.4mm pitch: AK4951AEN) and a 32-pin BGA (3.5mm x 3.5mm, 0.5mm pitch: AK4951EG) packages saving mounting area on the board. · Applications: IP Cameras, Digital Cameras, IC Recorders, Tablets, Wireless Headphones, Headsets
• Analog Input
(AK4951AEN) 3 Stereo Single-ended inputs with Selectors
(AK4951EG) 2 Stereo and 1 Monaural Single-ended inputs with Selectors
• Microphone Amplifier: +30dB ~ 0dB, 3dB Step
• Microphone Power Supply: 2.0V or 2.4V, Noise Level= −108dBV
• Digital ALC (Automatic Level Control)
- Setting Range: +36dB ~ −52.5dB, 0.375dB Step & Mute
• ADC Performance: S/(N+D): 83dB, DR, S/N: 88dB (MIC-Amp=+18dB)
S/(N+D): 85dB, DR, S/N: 96dB (MIC-Amp=0dB)
• Microphone Sensitivity Correction
• Automatic Wind Noise Reduction Filter
• 5-Band Notch Filter: Include Dynamic Gain Control
• Stereo Separation Emphasis Circuit
• Digital Microphone Interface
2. Playback Functions
• Digital ALC (Automatic Level Control)
- Setting Range: +36dB ~ −52.5dB, 0.375dB Step & Mute
• Sidetone Mixer & Volume Control (0dB ~ −18dB, 6dB Step)
• Digital Volume Control
- +12dB ~ −89.5dB, 0.5dB Step & Mute
• Capacitor-less Stereo Headphone Amplifier
- HP-Amplifier Performance: S/(N+D): 75dB@20mW, S/N: 97dB
- Output Power: 20mW@16Ω
- Pop Noise Free at Power-ON/OFF
• Mono Speaker Amplifier (with Stereo Line Output Switch)
- Speaker Amplifier Performance: S/(N+D): 75dB@250mW, S/N: 99dB
- BTL Output
- Output Power:
(AK4951AEN) 400mW@8Ω (SVDD=3.3V), 1W@8Ω (SVDD=5V)
(AK4951EG) 400mW@8Ω (AVDD=3.3V)
• Analog Mixing: BEEP Input
3. Power Management
4. Master Clock:
(1) PLL Mode
Frequencies: 11.2896MHz, 12MHz, 12.288MHz, 13.5MHz, 24MHz, 27MHz (MCKI pin)
32fs or 64fs (BICK pin)
(2) External Clock Mode
Frequencies: 256fs, 384fs, 512fs or 1024fs (MCKI pin)
5. Sampling Frequencies
• PLL Master Mode:
8kHz, 11.025kHz, 12kHz, 16kHz, 22.05kHz, 24kHz, 32kHz, 44.1kHz, 48kHz
• PLL Slave Mode (BICK pin): 8kHz ~ 48kHz
• EXT Master/Slave Mode:
8kHz ~ 48kHz (256fs, 384fs, 512fs), 8kHz 24kHz (1024fs)
6. Master/Slave Mode
7. Audio Interface Format: MSB First, 2’s complement
• ADC: 16/24bit MSB justified, 16/24bit I2S
• DAC: 16/24bit MSB justified, 16bit LSB justified, 24bit LSB justified, 16/24bit I2S
8. µP I/F:
(AK4951AEN) I2C Bus (Ver 1.0, 400kHz Fast-Mode)
(AK4951EG) 3-wire Serial, I2C Bus (Ver 1.0, 400kHz Fast-Mode)
9. Operating Temperature: Ta = −40 ~ 85°C
10. Power Supply
(AK4951AEN)
• Analog Power Supply (AVDD): 2.8 ~ 3.5V
• Speaker Power Supply (SVDD): 1.8 ~ 5.5V
• Digital & Headphone Power Supply (DVDD): 1.6 ~ 1.98V
• Digital I/O Power Supply (TVDD): 1.6 or (DVDD – 0.2) ~ 3.5V
(AK4951EG)
• Analog & Speaker Power Supply (AVDD): 2.8 ~ 3.5V
• Digital & Headphone Power Supply (DVDD): 1.6 ~ 1.98V
• Digital I/O Power Supply (TVDD): 1.6 or (DVDD – 0.2) ~ 3.5V
11. Package:
(AK4951AEN)
• 32-pin QFN (4 x 4 mm, 0.4mm pitch)
(AK4951EG)
• 32-pin BGA (3.5 x 3.5 mm, 0.5mm pitch)