The MAX9810 microphone preamplifier is intended for use inside electret condenser microphone (ECM) cartridges. The MAX9810 replaces the FET currently used with a high-gain, high-noise rejection, low output-impedance amplifier.
The MAX9810 microphone preamplifier is intended for use inside electret condenser microphone (ECM) cartridges. Current solutions use a FET as an impedance converter. FETs have limited gain, are susceptible to noise and require additional components external to the ECM cartridge for biasing and amplification. The MAX9810 replaces the FET with a high-gain, high-noise rejection, low-output-impedance amplifier. Designed to be integrated inside the ECM cartridge, the MAX9810 offers a flat frequency response, tightly controlled gain, increased sensitivity, and high-noise rejection greatly simplifying system design. Target applications include ECM cartridges in cell phones, PDAs, notebooks, and other portable audio devices.
The MAX9810 operates from a single 2.3V to 5.5V supply and consumes only 670µA of quiescent current. The device features an internally generated 1.5V DC bias and is available in three internally fixed gain options
(24dB, 27dB, and 30dB). The MAX9810 is specified over the extended temperature range (-40°C to +85°C) and comes in a tiny 4-bump chip-scale package (UCSP™) that is designed to fit inside the ECM cartridge.
Key Features
Applications/Uses
Replaces FET in Electret Condenser Microphone
2.3V to 5.5V Single-Supply Operation
Low-Impedance Output (<0.4Ω)
High PSRR: 82dB
Three High-Gain Options:
MAX9810A: 24dB
MAX9810B: 27dB
MAX9810C: 30dB
Internal Bias Voltage
Low Supply Current (670µA)
Rail-to-Rail Output
No Output Phase Reversal During Overload Conditions