FAN3850A: Microphone Pre-Amplifier with Digital Output

The FAN3850A integrates a pre-amplifier, LDO, and ADC that converts Electret Condenser Microphone (ECM) outputs to digital Pulse Density Modulation (PDM) data streams. The pre-amplifier accepts analog signals from the ECM and drives an over-sampled sigma delta Analog-to-Digital Converter (ADC) and outputs PDM data. The PDM digital audio has the advantage of noise rejection and easy interface to mobile handset processors.

The FAN3850A features an integrated LDO and is powered from the system supply rails up to 3.63V, with low power consumption of only 0.85mW and less than 20µW in Power-Down Mode.

Features

• Optimized for Mobile Handset and Notebook PC Microphone Applications
• Accepts Input from Electret Condenser Microphones (ECM)
• Pulse Density Modulation (PDM) Output
• Standard 5-Wire Digital Interface
• 19dB Gain Version Available(1)
• Low Input Capacitance, High PSR, 20Hz Pre-Amplifier
• Low-Power 1.5µA Sleep Mode
• Typical 470µA Supply Current
• SNR of 61dB(A)
• Total Harmonic Distortion 0.02%
• Input Clock Frequency Range of 1-4MHz
• Integrated Low Drop-Out Regulator (LDO)
• Small 1.26mm x 0.86mm 6-Ball WLCSP Package