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ALC4042

USB Audio Codec

The ALC4042 is a usb audio codec from Realtek Semiconductor. View the full ALC4042 datasheet below including key specifications, electrical characteristics, absolute maximum ratings.

Official ALC4042 datasheet (PDF) — the source this page was extracted from.

Category

USB Audio Codec

Package

MQFN-48 'Green' Package (6mm x 6mm)

ALC4042 Key Specifications

ParameterValue
Adc Snr94 dBA
Dac Snr100 dBA
Otp Memory16KB
Adc Resolution16/24/32-bit
Dac Resolution16/24/32-bit
I2s Resolution16/24/32-bit
Adc Sample Rate8KHz to 384KHz
Dac Sample Rate8KHz to 384KHz
Dmic Clock Rate0.1875MHz to 6MHz
I2s Sample Rate8KHz to 384KHz
Supply Voltage Range3.0V to 5.0V
Embedded Flash Memory64KB
Communication InterfacesUSB 2.0 (Full-Speed, High-Speed), I2S, I2C (master), SPI, UART, DMIC, SPDIF Out
Spdif Output Sample Rate44.1KHz to 192KHz
Operating Temperature Range-40°C to +85°C
Usb Suspend Current Consumption0.5mA

ALC4042 Overview

Part: ALC4042-CG — Realtek Semiconductor Corp.

Type: USB 2.0 Audio Codec with I2S Audio Controller and Hardware Active Noise Cancellation

Description: Single-chip USB 2.0 audio codec with embedded USB 2.0 to I2S and SPDIF interface, supporting high-resolution audio playback up to 32-bits and 384KHz sample rate, DSD decoder/encoder, and integrating a Class-G headphone amplifier.

Operating Conditions:

  • Supply voltage: 3.3 V
  • Operating temperature: -40 to +85 °C

Absolute Maximum Ratings:

  • Max supply voltage: 3.6 V
  • Max junction/storage temperature: 125 °C

Key Specs:

  • DAC SNR: 100 dBA
  • ADC SNR: 94 dBA
  • DAC Sample Rate: 8K/16K/22.05K/24K/32K/44.1K/48K/96K/176.4K/192K/384KHz
  • ADC Sample Rate: 8K/16K/22.05K/24K/32K/44.1K/48K/96K/176.4K/192K/384KHz
  • DAC Resolution: 16/24/32-bit
  • ADC Resolution: 16/24/32-bit
  • I2C Clock Frequency (SCL): 100 kHz (Standard Mode), 400 kHz (Fast Mode)
  • I2S Master Mode Bit Clock Frequency (BCLK): 1.536 MHz to 12.288 MHz

Features:

  • USB 2.0 function controller and transceiver
  • High speed MCU (Micro Processor Unit)
  • DC-to-DC regulators
  • Digital audio I2S interface
  • I2C control interface
  • SPI interface
  • Hardware Direct-Stream-Digital (DSD) native decoder (64Fs/128Fs/256Fs)
  • DSD over PCM (DoP) decoder and encoder (64Fs/128Fs)
  • Class-G ultra-low-power cap-saving headphone amplifier
  • Supports standard USB audio device class for Windows, Linux, Android
  • Configurable GPIO pins

Applications:

  • USB audio devices

Package:

  • QFN-48

ALC4042 Features

  • Digital-to-Analog Converter with 100dBA SNR

  • Analog-to-Digital Converter with 94dBA SNR

  • One stereo DAC supports 8K/16K/22.05K/24K/32K/44.1K/48K/96K/176.4K/192K/384KHz Sample Rate, 16/24/32-bit resolution

  • Two stereo ADCs support 8K/16K/22.05K/24K/32K/44.1K/48K/96K/176.4K/192K/384KHz Sample Rate, 16/24/32-bit resolution

  • Integrates hardware Direct-Stream-Digital (DSD) native decoder (64Fs/128Fs/256Fs) and DSD over PCM (DoP) decoder and encoder (64Fs/128Fs) for both I2S and headphone outputs

  • Class-G type amplifier for headphone output without DC blocking capacitors

  • 7-Band hardware EQ function for playback path (HPFx2, BPFx3, LBFx1, Biquadx1 )

  • 6-Band hardware EQ function for recording path (LPFx1, HPFx1, BPFx4)

  • 0.5mA current consumption for USB suspend and Ultra-Low-Power for headphone playback

  • 2 nd Gen. Realtek Proprietary Hardware Feed-Forward or Feedback Active Noise Cancellation (ANC)

  • One S/PDIF Out interface supports 44.1/48/88.2/96/176.4/192KHz sample rate for PCM format playback and AC-3 format data transfer

  • Single-ended analog microphone inputs with volume gain control in 0.375dB per step

  • Microphone boost gain settings of 0/10/20/30dB

  • Low noise microphone and programmable MICBIAS voltage level

  • Analog-to-analog and side tone pass-through path with volume gain adjustments

  • Audio jack detection feature

  • Supports combo jack with stereo headphone output and mono microphone input on a four-conductor headset jack for CTIA and OMTP type headsets without external components

  • 4-Button Headset in-line controls support Android Wired Audio Headset Specification with customizable multi-function

  • External active speaker humming noise cancellation

  • One I2S interface supports 8K/16K/22.05K/32K/44.1K/48K/88.2K/96K/176.4K/192K/384kHz sample rate and , 16/24/32-bit resolution

  • I2S digital interface supports TDM format up to 8CH output/input data transfer simultaneously

  • I2C control interface supports master mode

  • Two stereo digital microphone interfaces with shared clock rate support 0.1875M/0.375M/0.75M/1.5M/3M/6MHz

  • SPI (Serial Peripheral Interface, Mode 0~Mode 3) connection to serial flash for switching code and configuration of customized parameters

  • UART interface for external devices

  • Embedded 64K Byte flash and 16K Byte OTP for F/W programming

  • Built-in Analog LDO, supports voltage input supply range from 3.0V to 5.0V

  • 48-pin QFN 'Green' package

ALC4042 Applications

  • USB Docking Station for Notebook, Tablet, PCs
  • Mobile Phone audio accessary
  • Embedded USB audio applications
  • USB Type-C audio headset, microphone, speaker and generic audio accessories
  • USB gaming headset and generic audio accessories

ALC4042 Pin Configuration

Figure 2. Pin Assignments

ALC4042 Electrical Characteristics

Table 11. DC Characteristics

SymbolDescriptionMin.Typ.Max.Unit
V IHInput Voltage High2-3.3V
V ILInput Voltage Low-0.5-0.8V
V OHOutput Voltage High2.4--V
V OLOutput Voltage Low--0.4V
I OHOutput Current High--4mA
I OLOutput Current Low--4mA

Table 11. DC Characteristics

ALC4042 Absolute Maximum Ratings

Table 9. Absolute Maximum Ratings

ParameterSymbolMinimumTypicalMaximumUnits
Power Supplies Digital PowerVBus-0.35.05.5V
Ambient Operating TemperatureTa0-+70o C
Storage TemperatureTs-40-+125o C
ESD (Electrostatic Discharge)ESD (Electrostatic Discharge)ESD (Electrostatic Discharge)ESD (Electrostatic Discharge)ESD (Electrostatic Discharge)ESD (Electrostatic Discharge)
-Susceptibility VoltageSusceptibility VoltageSusceptibility VoltageSusceptibility VoltageSusceptibility Voltage
All PinsPass 3500VPass 3500VPass 3500VPass 3500VPass 3500V

Table 10. Recommended Operating Condition

SymbolDescriptionMin.Typ.Max.Unit
VBusSupply Voltage4.555.5V

ALC4042 Typical Application

To guarantee the best compatibility and performance quality in hardware design with specific requirements, please contact Realtek to receive the latest application circuits. Any modification made to the reference circuits is recommended to be reviewed by Realtek. Realtek may update the latest application circuits without modifying this datasheet.

Variants on the same datasheet

These parts have exact links to the same datasheet. They are candidates to compare, not verified drop-in replacements; check package, pinout and electrical limits.

Part NumberManufacturerPackage
ALC4042-CGRealtek SemiconductorMQFN-48 'Green' Package (6mm x 6mm)

More datasheets

All Realtek Semiconductor datasheets (14)

Data on this page is extracted from publicly available manufacturer datasheets using automated tools including AI. It may contain errors or omissions. Always verify specifications against the official manufacturer datasheet before making design or purchasing decisions. See our Terms of Service. Rights holders can submit a takedown request.

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