24-Bit Mono CODEC with HPF, ALC/Eq and MIC/SPK-Amp

  • Digi-Key
  • Inquiry
  • Evaluation Board Manual
  • Data Sheet


The AK4637 is a low power 24-bit Mono CODEC with a microphone and speaker amplifiers. The AK4637 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 and a high performance digital ALC (automatic level control) circuit. In addition, the output circuits include a speaker amplifier with 1W output power. It is suitable for various products as well as portable applications with recording/playback function.
The AK4637 are available in a small 20-pin QFN (3mm x 3mm, 0.4mm pitch: AK4637EN) package saving mounting area on the board.
Application: IP Camera, Digital Camera, MFP(Multi Function Printer), IoT

●1W Output SPK-Amp
The integrated monaural speaker amplifier is capable of 1W output power to directly drive an integrated speaker for playback requiring no external components.

●Fulfilling recording function
This device integrates a low-noise/low-power microphone amplifier and microphone power supply to enable high quality, realistic recoding performance. This is achieved by "Wind Noise Reduction Filter", "5-band Notch Filter" that allow for the removal of specific system tones/noises and a "Digital Automatic Level Control (ALC) Circuit" to optimizes recording levels.

●Low-power consumption
The AK4637EN achieves very low-power consumption: 6.5mW in monaural recording mode and 11.6mW in speaker playback mode, improving battery life of mobile devices.
24bit Mono CODEC AK4637

News Release

AK4637 2015/11/06
Mono CODEC with 1W Output SPK-Amp; the AK4637 is suitable for IoT applications.

Global Web Distributor Digi-Key Distributors/ Representatives

Key Features

1. Recording Functions
     •Analog Input
          1 Monaural Single-ended input or Differential input
     •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): 84dB, DR, S/N: 95dB (MIC-Amp=0dB)
     •Wind Noise Reduction Filter
     •5-Band Notch Filter: Include Dynamic Gain Control
     •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
     •Mono Speaker Amplifier (with Line Output Switch)
          -Speaker Amplifier Porformance: S/(N+D): 75dB@250mW, S/N: 97 dB
          -BTL Output
          -Output Power: 400mW@8Ω (AVDD=3.3V), 1W@8Ω (AVDD=5V)
     •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),
                       16fs, 32fs, 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: DSP Mode, 16/24bit MSB justified, 16/24bit I2S
     •DAC: DSP Mode, 16/24bit MSB justified, 16bit LSB justified, 16/24bit I2S
8. μP I/F: I2C Bus (Ver 1.0, 400kHz Fast-Mode)
9. Operating Temperature: Ta = -40 ~ 85℃
10. Power Supply
     •Analog Power Supply (AVDD): 2.8 ~ 5.5V
     •Digital Power Supply (DVDD): 1.6 ~ 1.98V
     •Digital I/O Power Supply (TVDD): 1.6 or (DVDD – 0.2) ~ 3.6V
11. Package:
     •20-pin QFN (3 x 3 mm, 0.4mm pitch) 

>> Read more

Block Diagram

Block Diagram

Page Top