MAX14 Microphone Amplifier ith AGC an LoNoise …

1 Click here to ask an associate for production status of specific part numbers. Microphone Amplifier with AGC and MAX9814. Low-Noise Microphone Bias General Description Features The MAX9814 is a low-cost, high-quality Microphone Automatic Gain Control (AGC). Amplifier with automatic gain control (AGC) and Three Gain Settings (40dB, 50dB, 60dB). low-noise Microphone bias. The device features a low-noise preamplifier, variable gain Amplifier (VGA), output Programmable Attack Time Amplifier , Microphone -bias-voltage generator, and AGC Programmable Attack and Release Ratio control circuitry.

2 To Supply Voltage Range The low-noise preamplifier has a fixed 12dB gain, while Low Input-Referred Noise Density of 30nV/ Hz the VGA gain automatically adjusts from 20dB to 0dB, Low THD: (typ). depending on the output voltage and the AGC threshold. The output Amplifier offers selectable gains of 8dB, 18dB, Low-Power Shutdown Mode and 28dB. With no compression, the cascade of the Internal Low-Noise Microphone Bias, 2V. amplifiers results in an overall gain of 40dB, 50dB, or 60dB. Available in the Space-Saving, 14-Pin TDFN. A trilevel digital input programs the output Amplifier gain.

3 An (3mm x 3mm) Package external resistive divider controls the AGC threshold and a single capacitor programs the attack/release times. A -40 C to +85 C Extended Temperature Range trilevel digital input programs the ratio of attack-to-release time. The hold time of the AGC is fixed at 30ms. The low- noise Microphone -bias-voltage generator can bias most electret microphones. Ordering Information appears at end of data sheet. The MAX9814 is available in the space-saving, 14-pin TDFN package. This device is specified over the -40 C to +85 C extended temperature range. Simplified Block Diagram Applications Digital Still Cameras TO Digital Video Cameras PDAs SHDN VDD.

4 MICBIAS LOW-NOISE MAX9814. Bluetooth Headsets RMICBIAS. REFERENCE AGC. Entertainment Systems ( , Karaoke). CIN COUT. MICIN GAIN. LNA VGA MICOUT. +8/+18/. +12dB +20dB/0dB. +28dB. Two-Way Communicators GND. High-Quality Portable Recorders IP Phones/Telephone Conferencing 19-0764; Rev 4; 2/20. 2022 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective owners. One Analog Way, Wilmington, MA 01887 | Tel: | 2022 Analog Devices, Inc. All rights reserved. MAX9814 Microphone Amplifier with AGC and Low-Noise Microphone Bias Absolute Maximum Ratings VDD to to +6V Continuous Power Dissipation (TA = +70 C).

5 All Other Pins to to (VDD + ) 14-Pin TDFN-EP. Output Short-Circuit (derate C above +70 C).. Continuous Current (MICOUT, MICBIAS).. 100mA Operating Temperature -40 C to +85 C. All Other 20mA Junction +150 C. Lead Temperature (soldering, 10s).. +300 C. Bump Temperature (soldering) +235 C. Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied.

6 Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Electrical Characteristics (VDD = , SHDN = VDD, CCT = 470nF, CCG = 2 F, GAIN = VDD, TA = TMIN to TMAX, unless otherwise specified. Typical values are at TA = +25 C.) (Note 1). PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS. GENERAL. Operating Voltage VDD Guaranteed by PSRR test V. Supply Current IDD 6 mA. Shutdown Supply Current ISHDN 1 A. Input-Referred Noise Density en BW = 20kHz, all gain settings 30 nV/ Hz Output Noise BW = 20kHz 430 VRMS. BW = 22Hz to 22kHz 61. Signal-to-Noise Ratio SNR (500mVRMS output signal) dB.

7 A-weighted 64. Dynamic Range DR (Note 2) 60 dB. fIN = 1kHz, BW = 20Hz to 20kHz, RL = 10k , VTH = 1V (threshold = 2VP-P), Total Harmonic Distortion Plus VIN = , VCT = 0V. THD+N %. Noise fIN = 1kHz, BW = 20Hz to 20kHz, RL = 10k , VTH = (threshold = 200mVP-P), VIN = 30mVRMS, VCT = 2V. Amplifier Input BIAS VIN V. Maximum Input Voltage VIN_MAX 1% THD 100 mVP-P. Input Impedance ZIN 100 k . GAIN = VDD 40 Maximum Gain A GAIN = GND 50 dB. GAIN = unconnected 60 GAIN = VDD 20 Minimum Gain GAIN = GND 30 dB. GAIN = unconnected 40 Maximum Output Level VOUT_RMS 1% THD+N, VTH = MICBIAS VRMS.

8 Regulated Output Level AGC enabled, VTH = VP-P. AGC Attack Time tATTACK CCT = 470nF (Note 3) ms A/R = GND 1:500. Attack/Release Ratio A/R A/R = VDD 1:2000 ms/ms A/R = unconnected 1:4000. Analog Devices 2. MAX9814 Microphone Amplifier with AGC and Low-Noise Microphone Bias Electrical Characteristics (continued). (VDD = , SHDN = VDD, CCT = 470nF, CCG = 2 F, GAIN = VDD, TA = TMIN to TMAX, unless otherwise specified. Typical values are at TA = +25 C.) (Note 1). PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS. MICOUT High Output Voltage VOH IOUT sourcing 1mA V. MICOUT Low Output Voltage VOL IOUT sinking 1mA 3 mV.

9 MICOUT Bias MICOUT unconnected V. Output Impedance ZOUT 50 . Minimum Resistive Load RLOAD_MIN 5 k . Maximum Capacitive Drive CLOAD_MAX 200 pF. Maximum Output Current I OUT_MAX 1% THD, RL = 500 1 2 mA. Output Short-Circuit Current ISC 3 8 mA. AGC mode; VDD = to (Note 4) 35 50. f = 217Hz, VRIPPLE = 100mVP-P (Note 5) 55. Power-Supply Rejection Ratio PSRR dB. f = 1kHz, VRIPPLE = 100mVP-P (Note 5) f = 10kHz, VRIPPLE = 100mVP-P (Note 5) 43. Microphone BIAS. Microphone Bias Voltage VMICBIAS IMICBIAS = V. Output Resistance RMICBIAS IMICBIAS = 1mA 1 . Output Noise Voltage VMICBIAS_NOISE IMICBIAS = , BW = 22Hz to 22kHz VRMS.

10 DC, VDD = to 70 80. Power-Supply Rejection Ratio PSRR IMICBIAS = , VRIPPLE = 100mVP-P, dB. 71. fIN = 1kHz TRILEVEL INPUTS (A/R, GAIN). A/R or GAIN = VDD. / 180k / 100k / 50k . Trilevel Input Leakage Current mA. A/R or GAIN = GND. / 180k / 100k / 50k . Input High Voltage VIH VDD x V. Input Low Voltage VIL VDD x V. Shutdown Enable Time tON 60 ms Shutdown Disable Time tOFF 40 ms DIGITAL INPUT (SHDN). SHDN Input Leakage Current -1 +1 A. Input High Voltage VIH V. Input Low Voltage VIL V. AGC THRESHOLD INPUT (TH). TH Input Leakage Current -1 +1 A. Note 1: Devices are production tested at TA = +25 C.