MAXIM Manuals

The MAX9860 is a low-power, voiceband, mono audio codec designed to provide a complete audio solution for wireless voice headsets and other mono voice audio devices.

The MAX9856 is a high-performance, low-power stereo audio CODEC designed for MP3, personal media players (PMPs), or other portable multimedia devices. Using on-board stereo DirectDrive® headphone amplifiers, the CODEC can output 30mW into stereo 32Ω headphones while operating from a single 1.8V power supply. Very low 9mW playback power consumption makes it an ideal choice for battery-powered applications. The MAX9856 provides microphone input amplifiers, plus flexible input selection, signal mixing, and automatic gain control (AGC). Comprehensive load-impedance sensing allows the MAX9856 to autodetect most common audio and audio/video headset and jack plug types. Outputs include stereo DirectDrive line outputs and DirectDrive headphone amplifiers. The stereo ADC can convert audio signals from either internal or external microphones that can be configured for single-ended or differential signal inputs. Line inputs can be configured as stereo, differential, or mono and fed through one channel of the microphone path. The analog inputs selected can be gain ranged or mixed with other input sources prior to conversion to digital. The ADC path also features programmable digital highpass filters to remove DC offset voltages and wind noise. The MAX9856 supports all common sample rates from 8kHz to 48kHz in both master and slave mode. The serial digital audio interfaces support a variety of formats including I2S, left-justified, and PCM modes. The MAX9856 is a leading low-power, high-performance stereo audio CODEC that is ideal for MP3 players, portable audio products, and other portable devices.

This document describes the features of the MAX9814 audio amplifier.

The MAX4063 is a differential-input microphone preamplifier optimized for high-performance, portable applications. The device features two selectable inputs, differential outputs, adjustable gain, an integrated low-noise bias source, and a low-power shutdown mode. Two input paths provide both differential and single-ended microphone sensing. The high-noise rejection of the differential input is ideally suited to an internal microphone where system noise and long-run PC board traces can degrade low-level signals. The single-ended input provides a simple connection to an external microphone. The differential and single-ended inputs have independent, adjustable gains that are set with a single external resistor. Differential outputs provide a full-scale signal of up to 6VP-P from a single 3V supply, optimizing the dynamic range of the amplified signal. A complete shut-down mode reduces the supply current to only 0.3µA and disables the microphone bias for the ultimate in power savings. The MAX4063 operates from 2.4V to 5.5V and is specified over the extended -40°C to +85°C operating temperature range. The MAX4063 is available in both 16-pin TQFN (4mm x 4mm x 0.8mm) and 14-pin TSSOP packages.

MAX4060/MAX4061/MAX4062 are differential-input microphone preamplifiers optimized for notebook and PDA audio systems. These devices feature adjustable gain with excellent power-supply rejection and common-mode rejection ratios, making them ideal for low-noise applications in portable audio systems. The MAX4060/MAX4062 are capable of switching their output between the differential input and a single-ended auxiliary microphone amplifier input. In addition, the MAX4060/MAX4062 have a low-noise microphone bias generator. The differential gain of the MAX4061/MAX4062 is set with a single resistor. The MAX4060 has a fixed gain of 10V/V and is PC99/2001 compliant. The MAX4061 includes a complete shut-down mode. In shutdown, the supply current is reduced to 0.3µA and the current to the microphone bias is cut off for ultimate power savings. The MAX4060 operates from a 4.5V to 5.5V single sup- ply and the MAX4061/MAX4062 operate from 2.4V to 5.5V. All devices are specified over the extended oper- ating temperature range, -40°C to +85°C. The MAX4060/MAX4061 are available in tiny 8-pin TDFN (3mm x 3mm x 0.8mm) and 8-pin µMAX® packages. The MAX4062 is available in a 10-pin µMAX package.

The MAX4465-MAX4469 are micropower op amps optimized for use as microphone preamplifiers. They provide the ideal combination of an optimized gain bandwidth product vs. supply current, and low voltage operation in ultra-small packages. The MAX4465/ MAX4467/MAX4469 are unity-gain stable and deliver a 200kHz gain bandwidth from only 24µA of supply cur- rent. The MAX4466/MAX4468 are decompensated for a minimum stable gain of +5V/V and provide a 600kHz gain bandwidth product. In addition, these amplifiers feature Rail-to-Rail® outputs, high AVOL, plus excellent power-supply rejection and common-mode rejection ratios for operation in noisy environments. The MAX4467/MAX4468 include a complete shutdown mode. In shutdown, the amplifiers’ supply current is reduced to 5nA and the bias current to the external microphone is cut off for ultimate power savings. The single MAX4465/MAX4466 are offered in the ultra-small 5-pin SC70 package, while the single with shutdown MAX4467/MAX4468 and dual MAX4469 are available in the space-saving 8-pin SOT23 package.

The MAX9892 is an audio click-and-pop eliminator for portable multimedia devices. It operates from a 1.7V to 3.6V supply, connects to the output of the existing system amplifier and provides a low-impedance path to ground during startup and shutdown. The inputs INL and INR accept voltage swings from VDD to 5.5V below VDD. See the Setting the Supply Voltage section for more information. The power-up and power-down transients are shunted to ground to prevent clicks and pops from becoming audible. The MAX9892 features two low-impedance analog switches controlled by MUTE that opens and closes the switches. The switches are open during normal operation and have no impact on the output signal. During startup and shutdown of the amplifier, the MAX9892 can be activated to short the outputs to ground and prevent clicks and pops from pulling current through the headphones. The MAX9892 is available in 6-bump UCSP (1mm x 1.52mm x 0.6mm) and 6-pin µDFN (2mm x 2mm x 0.75mm) packages. The MAX9892 is specified over the -40°C to +85°C temperature range.

The DS1847 is a dual temperature-controlled nonvolatile variable resistor consisting of two 256-position linear variable resistors. The product includes two 10kΩ, 256-position resistors and one 10kΩ, 256-position resistor, incorporating a direct-to-digital temperature sensor. The settings of the variable resistors are stored in EEPROM memory and can be accessed over the 2-wire serial bus. The value of each variable resistor is determined by a temperature-addressed look-up table, which can assign a unique value to each resistor for every 2°C increment over the -40°C to +95°C range. The output of the digital temperature sensor is also available as a 13-bit, 2’s complement value over the serial bus.

The MAX5486 dual 40kΩ logarithmic taper volume control features a debounced pushbutton up/down interface that controls volume and balance in audio applications. Each potentiometer has 32 log-spaced tap points with a buffered wiper output to replace mechanical potentiometers. An integrated bias generator provides the required ((VDD + VSS) / 2) bias voltage, eliminating the need for costly external op-amp circuits in unipolar audio applications. A mode-indicator LED output indicates volume or balance control. Five integrated LED drivers indicate volume level or balance settings, depending on the status of the mode indicator. Use the MAX5486 digital inputs with momentary contact single-pole/single-throw (SPST) pushbutton switches. Each input includes internal debounced circuitry and a pullup resistor to VLOGIC. The MAX5486 advances the wiper setting once per button push. Maxim’s proprietary SmartWiper™ control eliminates the need for a microcomputer to increase the wiper transition rate. The accelerated auto-advance feature provides a wiper-changing rate at 4Hz for holding the control input low for more than 250ms and at 8Hz after 500ms and then at 11Hz after 1000ms (see Table 2). All of the MAX5486’s pushbutton inputs are debounced. The mute input allows a single pushbutton to change between volume control and the -90dB (typ) mute setting. The mode input toggles between volume and balance control. The click-and-pop suppression feature min

The MAX5440 is an integrated circuit from Texas Instruments. It is a volume controller that supports 40kΩ resistors and has an LED indicator. It can be used for stereo volume control, desktop speakers, multimedia docking stations, set-top boxes and automotive back-seat multimedia.

The MAX5407 is a 32-point audio logarithmic taper digital potentiometer with a resistance from 10kΩ to 1MΩ, 1dB resolution, and single supply of 2.7V-5.5V and 0.35uA static current

The MAX5408-MAX5411 are dual, logarithmic taper digital potentiometers from Texas Instruments, each with 32 tap points, which replace mechanical potentiometers in audio applications requiring digitally controlled resistors. The MAX5408/MAX5410 are dual potentiometers with one wiper per potentiometer, while the MAX5409/MAX5411 are dual potentiometers with two wipers per potentiometer. An SPI-compatible serial interface controls the wiper positions. The MAX5408-MAX5411 have a factory-set resistance of 10k ohms per potentiometer. A zero-crossing detect feature minimizes the audible noise generated by wiper transitions. The MAX5408-MAX5411 have nominal temperature coefficients of 35 ppm/°C end-to-end and 5 ppm/°C ratiometric. The MAX5408-MAX5411 are available in 16-pin QSOP and 16-pin thin QFN packages and are specified over the extended temperature range (-40°C to +85°C). Applications include stereo volume control, fading and balancing stereo signals, and mechanical potentiometer replacement.

MAX13325/MAX13326 are dual automotive audio line drivers with I2C control and diagnostic capabilities, providing a reliable differential interface between automotive audio components. They feature differential inputs and outputs, integrated output diagnostics, and can be controlled using an I2C interface or operate in standalone mode. The outputs can deliver up to 4VRMS signals with a fixed gain of 12dB or 0dB. The output diagnostics report conditions on a per channel basis, including short to GND, short to battery, overcurrent, overtemperature, and excessive offset. The output amplifiers can drive capacitive loads up to 4nF. MAX13325/MAX13326 are designed for automotive applications and can operate in a temperature range of -40°C to +105°C.

The MAX13335E/MAX13336E are high-fidelity stereo audio input amplifiers designed for automotive applications requiring audio-level detection and/or jack sensing capability.