ASAHI KASEI [AK4642EN]
MS0420-E-00 2005/09
- 1 -





GENERAL DESCRIPTION
The AK4642 features a stereo CODEC with a built-in Microphone-Amplifier, Headphone-Amplifier and
Speaker-Amplifier. Input circuits include a Microphone-Amplifier and an ALC (Auto Level Control) circuit
that is suitable for portable application with recording/playback function. The AK4642 is available in a
32pin QFN, utilizing less board space than competitive offerings.

FEATURES
1. Recording Function
• Stereo Mic Input (Full-differential or Single-ended)
• Stereo Line Input
• MIC Amplifier (+32dB/+26dB/+20dB or 0dB)
• Digital ALC (Automatic Level Control)
(+36dB ∼ −54dB, 0.375dB Step, Mute)
• ADC Performance: S/(N+D): 83dB, DR, S/N: 86dB (MIC-Amp=+20dB)
S/(N+D): 88dB, DR, S/N: 95dB (MIC-Amp=0dB)
• Wind-noise Reduction Filter
• Stereo Separation Emphasis
2. Playback Function
• Digital De-emphasis Filter (tc=50/15µs, fs=32kHz, 44.1kHz, 48kHz)
• Digital Volume (+12dB ∼ −115.0dB, 0.5dB Step, Mute)
• Digital ALC (Automatic Level Control)
(+36dB ∼ −54dB, 0.375dB Step, Mute)
• Stereo Separation Emphasis
• Stereo Line Output
- Performance: S/(N+D): 88dB, S/N: 92dB
• Stereo Headphone-Amp
- S/(N+D): 70dB, S/N: 90dB
- Output Power: 62mW@16Ω (HVDD=3.3V)
- Pop Noise Free at Power ON/OFF
• Mono Speaker-Amp
- S/(N+D): 50dB@240mW, S/N: 90dB
- BTL Output
- Availbable for both Dynamic and Piezo Speaker
- Output Power: 400mW@8Ω (HVDD=3.3V)
3.0Vrms@50Ω (HVDD=5V)
• Analog Mixing: Mono Input
3. Power Management
4. Master Clock:
(1) PLL Mode
• Frequencies:
11.2896MHz, 12MHz, 12.288MHz, 13.5MHz, 24MHz, 27MHz (MCKI pin)
1fs (LRCK pin)
32fs or 64fs (BICK pin)
(2) External Clock Mode
• Frequencies: 256fs, 512fs or 1024fs (MCKI pin)
5. Output Master Clock Frequencies: 32fs/64fs/128fs/256fs
Stereo CODEC with MIC/HP/SPK-AMP
AK4642EN