MAX9814_09

19-0764; Rev 2; 6/09 KIT ATION EVALU BLE AVAILA Microphone Amplifier with AGC and Low-Noise Microphone Bias General Description Features o Automatic Gain Control (AGC) o Three Gain Settings (40dB, 50dB, 60dB) o Programmable Attack Time o Programmable Attack and Release Ratio o 2.7V to 5.5V Supply Voltage Range o Low Input-Referred Noise Density of 30nV/√Hz o Low THD: 0.04% (typ) o Low-Power Shutdown Mode o Internal Low-Noise Microphone Bias, 2V o Available in the Space-Saving, 14-Pin TDFN (3mm x 3mm) Package o -40°C to +85°C Extended Temperature Range MAX9814 The MAX9814 is a low-cost, high-quality microphone amplifier with automatic gain control (AGC) and lownoise microphone bias. The device features a low-noise preamplifier, variable gain amplifier (VGA), output amplifier, microphone-bias-voltage generator and AGC control circuitry. The low-noise preamplifier has a fixed 12dB gain, while the VGA gain automatically adjusts from 20dB to 0dB, depending on the output voltage and the AGC threshold. The output amplifier offers selectable gains of 8dB, 18dB, and 28dB. With no compression, the cascade of the amplifiers results in an overall gain of 40dB, 50dB, or 60dB. A trilevel digital input programs the output amplifier gain. An external resistive divider controls the AGC threshold and a single capacitor programs the attack/release times. A 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-biasvoltage generator can bias most electret microphones. 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. Ordering Information PART MAX9814ETD+T TEMP RANGE -40°C to +85°C PIN-PACKAGE 14 TDFN-EP* Applications Digital Still Cameras Digital Video Cameras PDAs Bluetooth Headsets Entertainment Systems (e.g., Karaoke) Two-Way Communicators High-Quality Portable Recorders IP Phones/Telephone Conferencing +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. Pin Configurations appear at end of data sheet. UCSP is a trademark of Maxim Integrated Products, Inc. Simplified Block Diagram 2.7V TO 5.5V SHDN MICBIAS RMICBIAS CIN MICIN LNA +12dB LOW-NOISE REFERENCE VDD AGC MAX9814 VGA +20dB/0dB GAIN +8/+18/ +28dB COUT MICOUT GND ________________________________________________________________ Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 ABSOLUTE MAXIMUM RATINGS VDD to GND ..............................................................-0.3V to +6V All Other Pins to GND.................................-0.3V to (VDD + 0.3V) Output Short-Circuit Duration.....................................Continuous Continuous Current (MICOUT, MICBIAS).......................±100mA All Other Pins ....................................................................±20mA Continuous Power Dissipation (TA = +70°C) 14-Pin TDFN-EP (derate 16.7mW/°C above +70°C) ........................1481.5mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Lead Temperature (soldering, 10s) .................................+300°C Bump Temperature (soldering) Reflow............................+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. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VDD = 3.3V, SHDN = VDD, CCT = 470nF, CCG = 2µF, GAIN = VDD, TA = TMIN to TMAX, unless otherwise specified. Typical values are at TA = +25°C.) (Note 1) PARAMETER GENERAL Operating Voltage Supply Current Shutdown Supply Current Input-Referred Noise Density Output Noise Signal-to-Noise Ratio Dynamic Range SNR DR VDD IDD ISHDN en BW = 20kHz, all gain settings BW = 20kHz BW = 22Hz to 22kHz (500mVRMS output signal) A-weighted (Note 2) fIN = 1kHz, BW = 20Hz to 20kHz, RL = 10kΩ, VTH = 1V (threshold = 2VP-P), VIN = 0.5mVRMS, VCT = 0V fIN = 1kHz, BW = 20Hz to 20kHz, RL = 10kΩ, VTH = 0.1V (threshold = 200mVP-P), VIN = 30mVRMS, VCT = 2V 1.14 1% THD GAIN = VDD Maximum Gain A GAIN = GND GAIN = unconnected GAIN = VDD Minimum Gain Maximum Output Level Regulated Output Level AGC Attack Time Attack/Release Ratio tATTACK A/R VOUT_RMS GAIN = GND GAIN = unconnected 1% THD+N, VTH = MICBIAS AGC enabled, VTH = 0.7V CCT = 470nF (Note 3) A/R = GND A/R = VDD A/R = unconnected 1.26 39.5 49.5 59.5 18.7 29.0 38.7 Guaranteed by PSRR test 2.7 3.1 0.01 30 430 61 64 60 0.04 % 0.2 1.23 100 100 40 50 60 20 30 40 0.707 1.40 1.1 1:500 1:2000 1:4000 ms/ms 1.54 40.5 50.6 60.5 20.5 30.8 40.5 VRMS VP-P ms dB dB 1.32 V mVP-P kΩ dB 5.5 6 1 V mA µA nV/√Hz µVRMS dB SYMBOL CONDITIONS MIN TYP MAX UNITS Total Harmonic Distortion Plus Noise THD+N Amplifier Input BIAS Maximum Input Voltage Input Impedance VIN VIN_MAX ZIN 2 _______________________________________________________________________________________ Microphone Amplifier with AGC and Low-Noise Microphone Bias ELECTRICAL CHARACTERISTICS (continued) (VDD = 3.3V, SHDN = VDD, CCT = 470nF, CCG = 2µF, GAIN = VDD, TA = TMIN to TMAX, unless otherwise specified. Typical values are at TA = +25°C.) (Note 1) PARAMETER MICOUT High Output Voltage MICOUT Low Output Voltage MICOUT Bias Output Impedance Minimum Resistive Load Maximum Capacitive Drive Maximum Output Current Output Short-Circuit Current ZOUT RLOAD_MIN CLOAD_MAX IOUT_MAX ISC AGC mode; VDD = 2.7V to 5.5V (Note 4) Power-Supply Rejection Ratio PSRR f = 217Hz, VRIPPLE = 100mVP-P (Note 5) f = 1kHz, VRIPPLE = 100mVP-P (Note 5) f = 10kHz, VRIPPLE = 100mVP-P (Note 5) MICROPHONE BIAS Microphone Bias Voltage Output Resistance Output Noise Voltage Power-Supply Rejection Ratio TRILEVEL INPUTS (A/R, GAIN) A/R or GAIN = VDD Tri-Level Input Leakage Current A/R or GAIN = GND Input High Voltage Input Low Voltage Shutdown Enable Time Shutdown Disable Time DIGITAL INPUT (SHDN) SHDN Input Leakage Current Input High Voltage Input Low Voltage AGC THRESHOLD INPUT (TH) TH Input Leakage Current -1 +1 µA VIH VIL -1 1.3 0.5 +1 µA V V VIH VIL tON tOFF 60 40 0.5VDD 0.5VDD 0.5VDD / 180kΩ / 100kΩ / 50kΩ 0.5VDD 0.5VDD 0.5VDD / 180kΩ / 100kΩ / 50kΩ VDD x 0.7 VDD x 0.3 V V ms ms VMICBIAS RMICBIAS IMICBIAS = 0.5mA IMICBIAS = 1mA DC, VDD = 2.7V to 5.5V PSRR IMICBIAS = 0.5mA, VRIPPLE = 100mVP-P, fIN = 1kHz 70 1.84 2.0 1 5.5 80 71 dB 2.18 V Ω µVRMS 1% THD, RL = 500Ω 3 35 SYMBOL VOH VOL CONDITIONS IOUT sourcing 1mA IOUT sinking 1mA MICOUT unconnected 1.14 MIN TYP 2.45 3 1.23 50 5 200 1 8 50 55 52.5 43 dB 2 1.32 MAX UNITS V mV V Ω kΩ pF mA mA MAX9814 VMICBIAS_NOISE IMICBIAS = 0.5mA, BW = 22Hz to 22kHz mA Note 1: Note 2: Note 3: Note 4: Note 5: Devices are production tested at TA = +25°C. Limits over temperature are guaranteed by design. Dynamic range is calculated using the EIAJ method. The input is applied at -60dBFS (0.707µVRMS), fIN = 1kHz. Attack time measured as time from AGC trigger to gain reaching 90% of its final value. CG is connected to an external DC voltage source, and adjusted until VMICOUT = 1.23V. CG connected to GND with 2.2µF. _______________________________________________________________________________________ 3 Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 Typical Operating Characteristics (VDD = 5V, CCT = 470nF, CCG = 2.2µF, VTH = VMICBIAS x 0.4, GAIN = VDD (40dB), AGC disabled, no load, RL = 10kΩ, COUT = 1µF, TA = +25°C, unless otherwise noted.) GAIN vs. FREQUENCY MAX9814 toc01 POWER-SUPPLY REJECTION RATIO vs. FREQUENCY MAX9814 toc02 MICBIAS POWER-SUPPLY REJECTION RATIO vs. FREQUENCY -40 -50 PSRR (dB) -60 -70 -80 -90 -100 VRIPPLE = 200mVP-P -110 10 100 1k FREQUENCY (Hz) 10k 100k MAX9814 toc03 80 70 60 GAIN (dB) GAIN = UNCONNECTED 0 -10 -20 PSRR (dB) -30 -40 -50 -30 50 40 30 20 10 0 10 100 1k FREQUENCY (Hz) 10k 100k GAIN = 0 GAIN = 1 -60 -70 VRIPPLE = 200mVP-P -80 10 100 1k FREQUENCY (Hz) 10k 100k SUPPLY CURRENT vs. SUPPLY VOLTAGE MAX9814 toc04 SHUTDOWN CURRENT vs. SUPPLY VOLTAGE MAX9814 toc05 MICROPHONE BIAS VOLTAGE vs. MICROPHONE BIAS SOURCE CURRENT MAX9814 toc06 3.5 3.4 3.3 SUPPLY CURRENT (mA) 3.2 3.1 3.0 2.9 2.8 2.7 2.6 2.5 2.5 3.0 3.5 4.0 4.5 5.0 5.5 0.5 2.5 SHUTDOWN CURRENT (nA) 0.4 2.0 VMICBIAS VOLTAGE (V) 0.3 1.5 0.2 1.0 0.1 0.5 0 6.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) 0 0 5 10 15 IMICBIAS (mA) 20 25 30 TOTAL HARMONIC DISTORTION PLUS NOISE vs. FREQUENCY MAX9814 toc07 TOTAL HARMONIC DISTORTION PLUS NOISE vs. OUTPUT VOLTAGE MAX9814 toc08 INPUT-REFERRED NOISE vs. FREQUENCY INPUT-REFERRED NOISE (µVRMS/√Hz) MICIN AC-COUPLED TO GND MAX9814 toc09 10 VOUT = 800mVRMS 10 1000 1 THD+N (%) THD+N (%) 1 fIN = 300Hz, 1kHz, and 3kHz 100 0.1 0.1 10 fIN = 10kHz 0.01 10 100 1k FREQUENCY (Hz) 10k 100k 0.01 0 0.5 1.0 1.5 OUTPUT VOLTAGE (VRMS) 1 0.01 0.1 1 FREQUENCY (kHz) 10 100 4 _______________________________________________________________________________________ Microphone Amplifier with AGC and Low-Noise Microphone Bias Typical Operating Characteristics (continued) (VDD = 5V, CCT = 470nF, CCG = 2.2µF, VTH = VMICBIAS x 0.4, GAIN = VDD (40dB), AGC disabled, no load, RL = 10kΩ, COUT = 1µF, TA = +25°C, unless otherwise noted.) MICBIAS NOISE vs. FREQUENCY MAX9814 toc10 MAX9814 SMALL-SIGNAL PULSE RESPONSE VMICIN 10mV/div 0V MAX9814 toc11 TURN-ON RESPONSE VSHDN 5V/div 0V VMICBIAS 2V/div 0V MAX9814 toc12 10,000 MICBIAS NOISE (nVRMS/√Hz) 1000 VMICOUT 500mV/div 100 0V CL = 10pF 10 10 100 1k FREQUENCY (Hz) 10k 100k 200µs/div VMICOUT 1V/div 0V 20ms/div VOUT vs. VIN MAX9814 toc13 VOUT vs. VIN MAX9814 toc14 VOUT vs. VIN MAX9814 toc15 1.00 VTH = 1V 0.75 VOUT (VRMS) 1.00 VTH = 1V 0.75 VOUT (VRMS) 1.00 VTH = 1V 0.75 VOUT (VRMS) 0.50 VTH = 0.75V 0.25 VTH = 0.5V 0 0 50 VIN (mVRMS) 100 150 AGC ENABLED GAIN = 1 0.50 VTH = 0.75V 0.25 VTH = 0.5V 0 0 10 20 VIN (mVRMS) AGC ENABLED GAIN = 0 30 40 0.50 VTH = 0.75V 0.25 VTH = 0.5V AGC ENABLED GAIN = UNCONNECTED 0 0 5 VIN (mVRMS) 10 15 ATTACK TIME MAX9814 toc16 ATTACK TIME MAX9814 toc17 HOLD AND RELEASE TIME MAX9814 toc18 VMICOUT 500mV/div VMICOUT 500mV/div VMICOUT 500mV/div 0V CCT = 47nF 200µs/div 0V CCT = 100nF 200µs/div 0V CCT = 47nF A/R = GND 20ms/div _______________________________________________________________________________________ 5 Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 Typical Operating Characteristics (continued) (VDD = 5V, CCT = 470nF, CCG = 2.2µF, VTH = VMICBIAS x 0.4, GAIN = VDD (40dB), AGC disabled, no load, RL = 10kΩ, COUT = 1µF, TA = +25°C, unless otherwise noted.) HOLD AND RELEASE TIME MAX9814 toc19 HOLD AND RELEASE TIME MAX9814 toc20 VMICOUT 500mV/div VMICOUT 500mV/div 0V CCT = 47nF A/R = VDD 40ms/div 0V CCT = 47nF A/R = UNCONNECTED 100ms/div Pin Description PIN TDFN 1 2 3 4, 11 5 6 7 8 CT SHDN CG N.C. VDD MICOUT GND MICIN Timing Capacitor Connection. Connect a capacitor to CT to control the Attack and Release times of the AGC. Active-Low Shutdown Control Amplifier DC Offset Adjust. Connect a 2.2µF capacitor to GND to ensure zero offset at the output. No Connection. Connect to GND. Power Supply. Bypass to GND with a 1µF capacitor. Amplifier Output Ground Microphone Noninverting Input Tri-Level Attack and Release Ratio Select. Controls the ratio of attack time to release time for the AGC circuit. A/R = GND: Attack/Release Ratio is 1:500 A/R = VDD: Attack/Release Ratio is 1:2000 A/R = Unconnected: Attack/Release Ratio is 1:4000 Tri-Level Amplifier Gain Control. GAIN = VDD, gain set to 40dB. GAIN = GND, gain set to 50dB. GAIN = Unconnected, uncompressed gain set to 60dB. Amplifier Bias. Bypass to GND with a 0.47µF capacitor. Microphone Bias Output AGC Threshold Control. TH voltage sets gain control threshold. Connect TH to MICBIAS to disable the AGC. Exposed Pad. Connect the TDFN EP to GND. NAME FUNCTION 9 A/R 10 GAIN 12 13 14 — BIAS MICBIAS TH EP 6 _______________________________________________________________________________________ Microphone Amplifier with AGC and Low-Noise Microphone Bias Detailed Description The MAX9814 is a low-cost, high-quality microphone amplifier with automatic gain control (AGC) and a lownoise microphone bias. The MAX9814 consists of several distinct circuits: a low-noise preamplifier, a variable gain amplifier (VGA), an output amplifier, a microphonebias-voltage generator, and AGC control circuitry. An internal microphone bias voltage generator provides a 2V bias that is suitable for most electret condenser microphones. The MAX9814 amplifies the input in three distinct stages. In the first stage, the input is buffered and amplified through the low-noise preamplifier with a gain of 12dB. The second stage consists of the VGA controlled by the AGC. The VGA/AGC combination is capable of varying the gain from 20dB to 0dB. The output amplifier is the final stage in which a fixed gain of 8dB, 18dB, 20dB is programmed through a single tri-level logic input. With no compression from the AGC, the MAX9814 is capable of providing 40dB, 50dB, or 60dB gain. The MAX9814’s AGC controls the gain by first detecting that the output voltage has exceeded a preset limit. The microphone amplifier gain is then reduced with a selectable time constant to correct for the excessive output-voltage amplitude. This process is known as the attack time. When the output signal subsequently lowers in amplitude, the gain is held at the reduced state for a short period before slowly increasing to the normal value. This process is known as the hold and release time. The speed at which the amplifiers adjust to changing input signals is set by the external timing capacitor C CT and the voltage applied to A/R. The AGC threshold can be set by adjusting V TH . Gain reduction is a function of input signal amplitude with a maximum AGC attenuation of 20dB. Figure 2 shows the effect of an input burst exceeding the preset limit, output attack, hold and release times. If the attack and release times are configured to respond too fast, audible artifacts often described as “pumping” or “breathing” can occur as the gain is rapidly adjusted to follow the dynamics of the signal. For best results, adjust the time constant of the AGC to accommodate the source material. For applications in which music CDs are the main audio source, a 160µs attack time with an 80ms release time is recommended. Music applications typically require a shorter release time than voice or movie content. MAX9814 Automatic Gain Control (AGC) A device without AGC experiences clipping at the output when too much gain is applied to the input. AGC prevents clipping at the output when too much gain is applied to the input, eliminating output clipping. Figure 1 shows a comparison of an over-gained microphone input with and without AGC. MAX9814 AGC DISABLED MAX9814 fig01a MAX9814 AGC ENABLED MAX9814 fig01b 0V VMICIN 100mV/div 0V VMICIN 100mV/div 0V VMICOUT (AC-COUPLED) 1V/div 0V VMICOUT (AC-COUPLED) 1V/div 400µs/div 400µs/div Figure 1. Microphone Input with and Without AGC _______________________________________________________________________________________ 7 Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 and setting the attack-to-release time ratio by configuring A/R as shown in Table 1: HOLD VCT 500mV/div ATTACK 0V VMICOUT (AC-COUPLED) 1V/div RELEASE • Use a small ratio to maximize the speed of the AGC. • Use a large ratio to maximize the sound quality and prevent repeated excursions above the threshold from being independently adjusted by the AGC. 0V AGC Output Threshold The output threshold that activates AGC is adjustable through the use of an external resistive divider. Once the divider is set, AGC reduces the gain to match the output voltage to the voltage set at the TH input. Microphone Bias 10ms/div Figure 2. Input Burst Exceeding AGC Limit Attack Time The attack time is the time it takes for the AGC to reduce the gain after the input signal has exceeded the threshold level. The gain attenuation during the attack time is exponential, and defined as one-time constant. The time constant of the attack is given by 2400 x CCT seconds (where CCT is the external timing capacitor): • Use a short attack time for the AGC to react quickly to transient signals, such as snare drum beats (music) or gun shots (DVD). • Use a longer attack time to allow the AGC to ignore short-duration peaks and only reduce the gain when a noticeable increase in loudness occurs. Shortduration peaks are not reduced, but louder passages are. This allows the louder passages to be reduced in volume, thereby maximizing output dynamic range. Hold Time Hold time is the delay after the signal falls below the threshold level before the release phase is initiated. Hold time is internally set to 30ms and nonadjustable. The hold time is cancelled by any signal exceeding the set threshold level, and the attack time is reinitiated. Release Time The release time is how long it takes for the gain to return to its normal level after the output signal has fallen below the threshold level and 30ms hold time has expired. Release time is defined as release from a 20dB gain compression to 10% of the nominal gain setting after the input signal has fallen below the TH threshold and the 30ms hold time has expired. Release time is adjustable and has a minimum of 25ms. The release time is set by picking an attack time using CCT 8 The MAX9814 features an internal low-noise microphone bias voltage capable of driving most electret condenser microphones. The microphone bias is regulated at 2V to provide that the input signal to the lownoise preamplifier does not clip to ground. Applications Information Programming Attack and Release Times Attack and release times are set by selecting the capacitance value between CT and GND, and by setting the logic state of A/R (Table 1). A/R is a tri-level logic input that sets the attack-to-release time ratio. Table 1. Attack-and-Release Ratios A/R GND VDD Unconnected ATTACK/RELEASE RATIO 1:500 1:2000 1:4000 The attack and release times can be selected by utilizing the corresponding capacitances listed in Table 2. Table 2. Attack-and-Release Time CCT 22nF 47nF 68nF 100nF 220nF 470nF 680nF 1µF tATTACK (ms) 0.05 0.11 0.16 0.24 0.53 1.1 1.63 2.4 tRELEASE (ms) A/R = GND 25 55 80 120 265 550 815 1200 A/R = VDD 100 220 320 480 1060 2200 3260 4800 A/R = UNCONNECTED 200 440 640 960 2120 4400 6520 9600 _______________________________________________________________________________________ Microphone Amplifier with AGC and Low-Noise Microphone Bias Setting the AGC Threshold To set the output-voltage threshold at which the microphone output is clamped, an external resistor-divider must be connected from MICBIAS to ground with the output of the resistor-divider applied to TH. The voltage VTH determines the peak output-voltage threshold at which the output becomes clamped. The maximum signal swing at the output is then limited to two times VTH and remains at that level until the amplitude of the input signal is reduced. To disable AGC, connect TH to MICBIAS. Choose CIN such that f-3dB_IN is well below the lowest frequency of interest. Setting f-3dB_IN too high affects the amplifier’s low-frequency response. Use capacitors with low-voltage coefficient dielectrics. Aluminum electrolytic, tantalum, or film dielectric capacitors are good choices for AC-coupling capacitors. Capacitors with high-voltage coefficients, such as ceramics (non-C0G dielectrics), can result in increased distortion at low frequencies. MAX9814 Output Capacitor The output of the MAX9814 is biased at 1.23V. To eliminate the DC offset, an AC-coupling capacitor (COUT) must be used. Depending on the input resistance (RL) of the following stage, COUT and RL effectively form a highpass filter. The -3dB point of the highpass filter, assuming zero output impedance, is given by: f−3dB_OUT = 1 2π × RL × COUT Microphone Bias Resistor MICBIAS is capable of sourcing 20mA. Select a value for RMICBIAS that provides the desired bias current for the electret microphone. A value of 2.2kΩ is usually sufficient for a microphone of typical sensitivity. Consult the microphone data sheet for the recommended bias resistor. Bias Capacitor The BIAS output of the MAX9814 is internally buffered and provides a low-noise bias. Bypass BIAS with a 470nF capacitor to ground. Shutdown The MAX9814 features a low-power shutdown mode. When S HDN goes low, the supply current drops to 0.01µA, the output enters a high-impedance state, and the bias current to the microphone is switched off. Driving SHDN high enables the amplifier. Do not leave SHDN unconnected. Input Capacitor The input AC-coupling capacitor (CIN) and the input resistance (RIN) to the microphone amplifier form a highpass filter that removes any DC bias from an input signal (see the Typical Application Circuit/Functional Diagram). CIN prevents any DC components from the input-signal source from appearing at the amplifier outputs. The -3dB point of the highpass filter, assuming zero source impedance due to the input signal source, is given by: f−3dB_IN = 1 2π × RIN × CIN Power-Supply Bypassing and PCB Layout Bypass the power supply with a 0.1µF capacitor to ground. Reduce stray capacitance by minimizing trace lengths and place external components as close to the device as possible. Surface-mount components are recommended. In systems where analog and digital grounds are available, connect the MAX9814 to analog ground. _______________________________________________________________________________________ 9 Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 Typical Application Circuit/Functional Diagram VDD CBYPASS 1µF SHDN VDD MICBIAS MAX9814 BIAS CBIAS 0.47µF MICBIAS RMICBIAS 2.21kΩ MICIN CIN 0.1µF CT CCT 470nF CG CCG 2.2µF LNA VGA MICOUT COUT A/R TH VDD REF AGC GAIN R2 100kΩ R1 150kΩ ROUT GND *THE DEVICE HAS BEEN CONFIGURED WITH AN ATTACK TIME OF 1.1ms, 40dB GAIN, AND AN ATTACK-AND-RELEASE RATIO OF 1:500. 10 ______________________________________________________________________________________ Microphone Amplifier with AGC and Low-Noise Microphone Bias Pin Configuration PROCESS: BiCMOS MICBIAS Chip Information MAX9814 TOP VIEW TH 14 13 12 11 10 9 MAX9814 + 1 CT *EP 2 SHDN 3 CG 4 N.C. 5 VDD 6 MICOUT 7 GND TDFN ______________________________________________________________________________________ MICIN 8 GAIN BIAS N.C. A/R 11 Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 Package Information For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. PACKAGE TYPE 14 TDFN-EP PACKAGE CODE T1433-2 DOCUMENT NO. 21-0137 12 ______________________________________________________________________________________ 6, 8, &10L, DFN THIN.EPS Microphone Amplifier with AGC and Low-Noise Microphone Bias Package Information (continued) For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. MAX9814 COMMON DIMENSIONS SYMBOL A D E A1 L k A2 MIN. 0.70 2.90 2.90 0.00 0.20 MAX. 0.80 3.10 3.10 0.05 0.40 PACKAGE VARIATIONS PKG. CODE T633-2 T833-2 T833-3 T1033-1 T1033-2 T1433-1 T1433-2 N 6 8 8 10 10 14 14 D2 1.50±0.10 1.50±0.10 1.50±0.10 1.50±0.10 1.50±0.10 1.70±0.10 1.70±0.10 E2 2.30±0.10 2.30±0.10 2.30±0.10 2.30±0.10 2.30±0.10 2.30±0.10 2.30±0.10 e 0.95 BSC 0.65 BSC 0.65 BSC 0.50 BSC 0.50 BSC 0.40 BSC 0.40 BSC JEDEC SPEC MO229 / WEEA MO229 / WEEC MO229 / WEEC MO229 / WEED-3 MO229 / WEED-3 ------b 0.40±0.05 0.30±0.05 0.30±0.05 0.25±0.05 0.25±0.05 0.20±0.05 0.20±0.05 [(N/2)-1] x e 1.90 REF 1.95 REF 1.95 REF 2.00 REF 2.00 REF 2.40 REF 2.40 REF 0.25 MIN. 0.20 REF. ______________________________________________________________________________________ 13 Microphone Amplifier with AGC and Low-Noise Microphone Bias MAX9814 Revision History REVISION NUMBER 0 1 2 REVISION DATE 3/07 2/09 6/09 Initial release Updated Ordering Information, Absolute Maximum Ratings, Pin Description, and Pin Configuration sections to include EP for TDFN package Removed UCSP package DESCRIPTION PAGES CHANGED — 1, 2, 6, 11 1, 2, 6, 11, 12 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 14 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2009 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc.