MAX9814ETD+TG24

Audio Amplifiers Overview

The MAX9814ETD+T is a microphone amplifier with automatic gain control and low-noise microphone bias. It operates from a 2.7V to 5.5V supply, drawing 3.1mA typical current. The device provides selectable overall gains of 40dB, 50dB, or 60dB via a trilevel input. Input-referred noise density is 30nV/√Hz, with total harmonic distortion plus noise at 0.04% typically. It features an internal 2V microphone bias generator and a shutdown mode reducing current to 0.01µA. The component is housed in a 14-pin TDFN package and functions within a -40°C to +85°C temperature range.

Audio Amplifiers Feature Summary

• Integrates automatic gain control circuitry to prevent output clipping during loud audio events while amplifying distant sounds.
• Includes a low-noise preamplifier, variable gain amplifier, and output amplifier for high-fidelity signal processing.
• Features an internal low-noise microphone bias voltage generator suitable for electret condenser microphones.
• Supports programmable attack and release time ratios to optimize response for different audio sources.

Audio Amplifiers Applications

• Digital still cameras
• Digital video cameras
• Bluetooth headsets
• IP phones and telephone conferencing systems

Audio Amplifiers Procurement Notes

Verify the specific suffix 'G24' against official manufacturer documentation, as standard datasheets list 'MAX9814ETD+T'. Confirm RoHS compliance status and lead-free specifications directly with Analog Devices or Maxim Integrated. Ensure the ordering part number matches the exact pin configuration and thermal pad requirements for the 14-TDFN package before procurement.

Audio Amplifiers Selection Notes

Select this component for applications requiring integrated AGC to manage dynamic range without external logic. Consider the trilevel gain selection pins for hardware-based configuration flexibility. Evaluate the 30nV/√Hz noise performance against system sensitivity requirements. Verify that the 2V internal bias meets the power needs of the connected electret microphone.

Audio Amplifiers Part Context

The MAX9814 belongs to the Maxim Integrated (now Analog Devices) line of audio interface solutions designed for portable consumer electronics. It consolidates multiple analog stages into a single compact package, replacing discrete designs. This integration reduces board space and simplifies layout for battery-powered devices requiring high-quality voice capture.

Audio Amplifiers Replacement Considerations

Direct replacements include other parts from the MAX9814 family such as the MAX9814ETD/V+T. Cross-reference pinouts and electrical characteristics carefully when substituting with generic microphone amplifiers lacking integrated AGC.

Audio Amplifiers FAQ

How is the AGC threshold adjusted?

The AGC threshold is set using an external resistive divider connected between MICBIAS and ground, with the divider output applied to the TH pin.

What determines the attack and release times?

Attack and release times are programmed by connecting an external capacitor to the CT pin and setting the A/R pin to GND, VDD, or leaving it unconnected to select the ratio.