19-5964; Rev 0; 06/11 TION KIT EVALUA BLE IL AVA A Low-Power Headset Detectors with SEND/END Button Support Features The MAX14579E/MAX14579AE provide a simple solution for detecting the insertion and managing the operation of a 3.5mm stereo headset with a microphone. These devices integrate all circuitry required to detect SEND/ END button press events and generate required microphone bias voltages. S3.5mm Jack Insertion Detection SSimple Interface: One Input/Two Open-Drain Outputs SLow-Power Microphone Mode SLow-Noise, High-PSRR Microphone Bias Generator The devices are managed with only three GPIOs from the host controller to select between call mode and standby mode, and monitor the SEND/END and jack insertion status. In call mode, the low-noise LDO is enabled to provide DC bias to the externally preamplified microphone. In standby mode, microphone low-power pulsing is enabled to reduce supply current while waiting for a SEND/END button press event. Two open-drain outputs signal the host controller when an insertion/removal or SEND/END button press event occurs. SClick-and-Pop Suppression SHigh-ESD Protection on MIC and DETIN Inputs ±15kV Human Body Model (HBM) Applications Cell Phones e-Readers Tablet PCs The MAX14579E/MAX14579AE manage jack insertion detection by monitoring a 3.5mm socket with a normally open jack insertion switch. Ordering Information PART The devices are available in an 8-pin TDFN package, and are fully specified over the -40NC to +85NC extended temperature range. TEMP RANGE PIN-PACKAGE MAX14579EETA+ -40NC to +85NC 8 TDFN-EP* MAX14579AEETA+** -40NC to +85NC 8 TDFN-EP* +Denotes a lead(Pb)-free/RoHS compliant package. *EP = Exposed pad. **Future product—contact factory for availablity. Typical Operating Circuit ADC 1µF 3.3V 3.5mm SOCKET 3.3V MODE VCC CAP 0.22µF PROCESSOR 1MΩ MAX14579E RES SWD 3.3V 2.2kΩ 1MΩ 10kΩ DETIN DET EP/GND MIC AUDIO AMPLIFIER MICROPHONE AMPLIFIER 0.1µF ________________________________________________________________ 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. MAX14579E/MAX14579AE General Description MAX14579E/MAX14579AE Low-Power Headset Detectors with SEND/END Button Support ABSOLUTE MAXIMUM RATINGS (Voltages referenced to ground.) VCC, MODE, SWD, DET...........................................-0.3V to +6V CAP, MIC, DETIN, RES............................. -0.3V to (VCC + 0.3V) Continuous Current into Any Terminal........................... Q100mA Continuous Power Dissipation (TA = +70NC) TDFN (derate 11.9mW/NC above +70NC)..................953.5mW Operating Temperature Range........................... -40NC to +85NC Junction Temperature......................................................+150NC Storage Temperature Range............................. -65NC to +150NC Lead Temperature (soldering, 10s) ................................+300NC Soldering Temperature (reflow).......................................+260NC 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. PACKAGE THERMAL CHARACTERISTICS (Note 1) TDFN Junction-to-Ambient Thermal Resistance (BJA).........83.9NC/W Junction-to-Case Thermal Resistance (BJC).................37NC/W Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a fourlayer board. For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (VCC = 2.5V to 5.5V, CDETIN < 100pF, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = 3.6V, TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS 5.5 V 1.7 2.45 V MODE = low, DETIN = high 0.8 1.3 MODE = low, DETIN = low, IMIC = 300FA 8 11 MODE = high, DETIN = low, IMIC = 300FA 500 800 DC CHARACTERISTICS Supply Voltage Range VCC Undervoltage-Lockout Threshold VCC Supply Current DETIN Pullup Resistance Internal Microphone Bias Voltage VCC VCCUVLO ICC 2.5 VCC rising VCC = 2.8V RDETIN VBIAS 1000 MODE = low VCC MODE = high, DETIN = low 2.2 MIC SEND/END Detection Threshold DETIN Detection Threshold 0.9 Falling edge FA kI V 0.20 O VBIAS 0.22 O VBIAS 0.24 O VBIAS V 1/3 O VCC 1/2 O VCC 2/3 O VCC V 2 _______________________________________________________________________________________ Low-Power Headset Detectors with SEND/END Button Support (VCC = 2.5V to 5.5V, CDETIN < 100pF, TA = -40NC to +85NC, unless otherwise noted. Typical values are at VCC = 3.6V, TA = +25NC.) (Note 2) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS LINEAR REGULATOR (CAP) Minimum Bypass Capacitance COUT Output Current Limit ICAP VCAP < VLDO Output Voltage VLDO VCC = 2.8V 0.22 FF 4 mA 2.0 2.2 2.45 V Noise from VCC to CAP, f = 217Hz, VCC = 2.8V Q0.1V, ICAP = 300FA, MODE = high 100 dB NLDO VCC = 2.8V, IMIC = 300FA, f = 100Hz to 4000Hz 11 FVRMS tOFF VCC = 2.8V, RL = 2kI, VCAP from 90% to 10% 120 Fs LDO PSRR PSRRLDO LDO Noise LDO Turn-Off Time DIGITAL SIGNALS (MODE, SWD, DET) Input-Voltage High VIH Input-Voltage Low VIL Input Leakage Current IINLEAK Output Logic-High Leakage Current (Open Drain) IOH_LKG Output Logic-Low VOL 1.4 V -1 Output voltage = 5V ISINK = 1mA 0.4 V +1 FA 1 FA 0.4 V DYNAMIC CHARACTERISTICS MIC Low-Power Mode On-Time tMICLPO RMIC = 5kI, MPLP 120 Fs MIC Low-Power Mode Period tMICLPP RMIC = 5kI, MPLP 8 ms DETIN Debounce Time SEND/END Debounce Time tDETINDEB Falling edge tSEDEB MAX14579E 300 MAX14579AE 1000 ms 28 ms ESD PROTECTION MIC, DETIN Human Body Model Q15 kV All Other Pins Human Body Model Q2 kV Note 2: All units are production tested at TA = +25NC. Specifications over temperature are guaranteed by design. _______________________________________________________________________________________ 3 MAX14579E/MAX14579AE ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (MAX14579E, VCC = 3.3V, TA = +25NC, CDETIN < 100pF, unless otherwise noted.) MAX14579E toc01 SHUTDOWN MODE 4.0 VCC SUPPLY CURRENT vs. VOLTAGE 12 3.5 TA = +85°C 8 ICC (µA) TA = -40°C 2.5 2.0 1.5 2 TA = +85°C 0.5 TA = -40°C 4 TA = +25°C 1.0 TA = +25°C 6 0 0 3.5 2.5 4.5 5.5 3.5 2.5 VCC (V) CAP VOLTAGE vs. VCC 3.0 MAX14579E toc03 CALL MODE IMIC = 0µA 180 TA = +85°C ICAP = 0mA 2.5 160 2.0 140 VCAP (V) ICC (µA) 5.5 MAX14579E toc04 VCC SUPPLY CURRENT vs. VOLTAGE 200 4.5 VCC (V) TA = +25°C 120 TA = -40°C 1.5 1.0 100 0.5 80 60 0 3.5 2.5 4.5 5.5 3.5 2.5 VCC (V) CAP VOLTAGE vs. CURRENT 5.5 CAP VOLTAGE vs. TEMPERATURE 3.0 MAX14579E toc05 3.0 4.5 VCC (V) VCC = 3.3V 2.5 2.5 VCC = 2.8V ICAP = 0mA 2.0 VCAP (V) 2.0 MAX14579E toc06 ICC (µA) MPLP MODE IMIC = 0µA 10 3.0 MAX14579E toc02 VCC SUPPLY CURRENT vs. VOLTAGE 4.5 VCAP (V) MAX14579E/MAX14579AE Low-Power Headset Detectors with SEND/END Button Support 1.5 1.5 1.0 1.0 0.5 0.5 0 0 0 1 2 3 4 ICAP (mA) 5 6 7 -40 -15 10 35 60 TA (°C) 4 _______________________________________________________________________________________ 85 Low-Power Headset Detectors with SEND/END Button Support 2000 TA = +25°C 1500 TA = +85°C 1000 500 VCC = 2.8V ± 0.1V -20 PSRR TO CAP (dB) DROPOUT VOLTAGE (mV) TA = -40°C -40 -60 -80 -100 -120 0 0 1 2 3 4 5 6 10 7 100 1000 10,000 100,000 ICAP (mA) FREQUENCY (Hz) CAP NOISE DENSITY vs. FREQUENCY MICROPHONE LOW-POWER MODE OPERATION MAX14579E toc10 MAX14579E toc09 1.0 NOISE SPECTRAL DENSITY (µV/√Hz) 0 MAX14579E toc07 2500 MAX14579E toc08 CAP POWER-SUPPLY REJECTION RATIO vs. FREQUENCY CAP DROPOUT VOLTAGE vs. CAP CURRENT 0.9 0.8 3.3V 0.7 VMIC 1V/div 0.6 0.5 0.4 0V 0.3 0.2 0.1 0 100 1000 10,000 1ms/div FREQUENCY (Hz) DETIN DEBOUNCE TIMING (MODE = LOW) SWD DEBOUNCE TIMING MAX14579E toc11 100ms/div MAX14579E toc12 3.3V 3.3V VDETIN 1V/div VMIC 1V/div 0V 0V 3.3V VRES 2V/div 0V 3.3V VSWD 2V/div 0V 40ms/div _______________________________________________________________________________________ 5 MAX14579E/MAX14579AE Typical Operating Characteristics (continued) (MAX14579E, VCC = 3.3V, TA = +25NC, CDETIN < 100pF, unless otherwise noted.) MAX14579E/MAX14579AE Low-Power Headset Detectors with SEND/END Button Support Pin Configuration TOP VIEW MIC DETIN VCC CAP 8 7 6 5 + MAX14579E MAX14579AE *EP/GND 1 2 3 4 RES MODE SWD DET TDFN *CONNECT THE EXPOSED PAD (EP/GND) TO THE GROUND PLANE. Pin Description PIN NAME FUNCTION 1 RES 2 MODE 3 SWD SEND/END Button Detection Output. SWD asserts when a SEND/END button press event occurs. SWD is an active-low, open-drain output. 4 DET Jack Insertion Detection Open-Drain Output. DET is asserted when there is a 3.5mm jack inserted into the socket. DET is an active-low output. 5 CAP Internal LDO Output. Connect a 0.22FF ceramic (X5R, X7R, or better) capacitor between CAP and ground. 6 VCC Supply Voltage. Bypass VCC to ground with a 1FF ceramic capacitor. 7 DETIN Jack Insertion Detection Input. An internal comparator monitors DETIN for jack insertion/ removal events. 8 MIC Microphone Connection. During audio operation, a 2.2V bias voltage is supplied to MIC through RES. An internal comparator monitors MIC for SEND/END button press events. — EP Resistor Connection. Connect an external 2.2kI resistor from RES to MIC for microphone biasing. Microphone Mode Control Input. MODE selects the operating mode. See the MODE Control Input section for more information. Exposed Pad. The exposed pad is the ground connection for the device. Connect EP/GND to the ground plane. 6 _______________________________________________________________________________________ Low-Power Headset Detectors with SEND/END Button Support VCC VBIAS MAX14579E MAX14579AE MODE LOW-NOISE 2.2V LDO CAP CONTROL RES DEBOUNCE SWD MIC DEBOUNCE DET 0.22VBIAS VCC LM DETIN 0.5VCC Detailed Description The MAX14579E/MAX14579AE manage headsets by integrating 3.5mm jack insertion detection, microphone bias generation, and SEND/END button press detection. These devices feature a low-power microphone mode to reduce the high bias current required for microphone operation while it is not in use. The devices require only a single MODE input to select between call mode and low-power mode. See the Jack Insertion Detection section for details about the differences among the devices. Internal LDO Regulator The devices feature an internal low-noise, low-dropout regulator (LDO) for biasing the microphone connected to MIC. The LDO’s output voltage is set at 2.2V. The LDO is enabled and enters low-noise mode when the MODE input is logic-high and a jack is detected. Pull the MODE input low to put the LDO in low-power shutdown mode. Microphone Operation and Bias Voltage Generation An externally preamplified microphone is connected to MIC. Connect MIC to RES through an external 2.2kI resistor to bias the microphone. All the devices generate a bias voltage (VBIAS) at RES. VBIAS is generated either by the internal 2.2V (typ) LDO when the MODE input is logic-high or by VCC when the MODE input is logic-low. Microphone Low-Power Mode (MPLP) A microphone draws a large amount of current due to the required bias resistor when it is connected. This current is dissipated even while the microphone is not in use. The ICs feature internal circuitry to reduce this current while simultaneously detecting SEND/END button press events. _______________________________________________________________________________________ 7 MAX14579E/MAX14579AE Functional Diagram MAX14579E/MAX14579AE Low-Power Headset Detectors with SEND/END Button Support When microphone low-power mode (MPLP) is entered by pulling the MODE input low, the bias voltage is disconnected from the RES output and is reconnected for a short duration every 8ms (typ) to check for a SEND/END button press event. MPLP is exited when the MODE input transitions to logic-high. Note that VBIAS is permanently disconnected from RES when no jack is inserted and microphone low-power mode is not entered. Jack Insertion Detection The MAX14579E/MAX14579AE detect jack insertion/ removal events by monitoring the DETIN input. Debounce circuitry ensures that transient voltages do not force the device to enter or exit MPLP due to false jack insertion/ removal detection. MAX14579E Detection The MAX14579E/MAX14579AEs' DETIN input has an internal 1MI pullup resistor to VCC. DETIN monitors a normally open insertion detection switch connected between DETIN and an audio line. DETIN is pulled high by the resistor, and DET is logic-high when no jack is inserted into the socket. DETIN is pulled low by the switch, and DET is logic-low when a jack is inserted. Ensure that the total capacitance on DETIN is less than 100pF. SEND/END Button Press Detection The MAX14579E/MAX14579AE detect SEND/END button press events by monitoring the MIC input. A SEND/ END button press is detected if the voltage at MIC falls below the MIC SEND/END detection threshold (0.22 O VBIAS (typ)) for longer than the debounce time (typ). The SWD output is logic-low for the duration of the SEND/ END button press event following the debounce period. The SEND/END detection circuitry is active whenever a jack is inserted. The debounce period built into the SEND/END button press detection allows the mechanical SEND/END button to reach steady-state before applying the microphone bias. This mitigates click-and-pop noise. MODE Control Input An external host processor controls the MODE input. Table 1 shows the behavior of the device based on the MODE input and jack insertion status. The device enters call mode when MODE is logic-high and a jack is detected, enabling the LDO immediately in low-noise mode (LNM). The 2.2V (typ) LDO output powers VBIAS and is connected to the microphone through an external 2.2kI bias resistor. Pull MODE low to put the device in standby mode. In standby mode, VCC powers VBIAS, the LDO enters shutdown mode (SDM), and the microphone bias connection either turns off permanently if no jack is inserted or enters MPLP if a jack is inserted. The MODE input is compatible with 1.8V logic with VCC voltages up to 5.5V. Applications Information Typical Connections for 3.5mm Jacks There are two typical 3.5mm jacks: tip-ring-ring-sleeve (TRRS) with four conductors (Figure 1a) and tip-ringsleeve (TRS) with three conductors (Figure 1b). The most common configuration of the TRRS jack is to use rings 1 and 2 for audio signals, ring 3 for ground, and ring 4 for a microphone. The TRS jack typically uses rings 1 and 2 for audio signals and rings 3 and 4 as ground. Table 1. Operating Modes MODE DETIN/MIC INSERTED LOW LOW LDO Mode MIC Bias Mode HIGH HIGH LOW SDM SDM MPLP 1 Off 2 3 2.2kI 4 (a) 1 2 HIGH 3 4 (b) Figure 1. Typical 3.5mm Jacks 8 _______________________________________________________________________________________ Off Low-Power Headset Detectors with SEND/END Button Support Headset with No Microphone When the 3.5mm jack in Figure 2a is inserted, the MIC input is pulled low permanently by the ground connection on the sleeve and the SWD output is logic-low permanently. This type of headset is supported by implementing a timeout period in software to recognize that the permanent logic-low is not due to a very long SEND/ END button press event. 1 2 4 SPEAKER SPEAKER (a) 1 2 3 4 MICROPHONE SPEAKER Headset with Microphone and Normally Open SEND/END Button in Parallel When the 3.5mm jack in Figure 2b is inserted, the MIC input is pulled below the threshold only during a SEND/ END button press event. The SWD output is logic-high when the SEND/END button is pressed for more than the debounce time. Headset with Normally Open SEND/END Button and Resistive Remote Control The devices support the 3.5mm jack with a microphone and two buttons in Figure 2c that is the standard Windows Mobile™ configuration. The threshold is set to detect a button press, regardless of which button is pressed. 3 SEND/ END SPEAKER (b) 1 2 3 4 SPEAKER SEND/ END 600Ω 200Ω MICROPHONE SPEAKER High-ESD Protection Electrostatic discharge (ESD)-protection structures are incorporated on all pins to protect against electrostatic discharges up to Q2kV Human Body Model (HBM) encountered during handling and assembly. DETIN and MIC are further protected against ESD up to Q15kV (HBM) without damage. After an ESD event, all the devices continue to function without latchup. (c) Figure 2. Supported 3.5mm Accessory Configurations Windows Mobile is a registered trademark of Microsoft Corporation. _______________________________________________________________________________________ 9 MAX14579E/MAX14579AE Supported Accessories The devices support all standard configurations of headsets with a microphone and SEND/END button on a TRS or TRRS 3.5mm jack. Figure 2 shows the supported connections of the speakers, SEND/END button, and microphone to the jack. MAX14579E/MAX14579AE Low-Power Headset Detectors with SEND/END Button Support RC 1MΩ CHARGE-CURRENT LIMIT RESISTOR HIGHVOLTAGE DC SOURCE CS 100pF RD 1.5kΩ IP 100% 90% DISCHARGE RESISTANCE STORAGE CAPACITOR Ir PEAK-TO-PEAK RINGING (NOT DRAWN TO SCALE) AMPS DEVICE UNDER TEST Figure 3. Human Body ESD Test Model 36.8% 10% 0 0 TIME tRL tDL CURRENT WAVEFORM Figure 4. Human Body Current Waveform ESD Test Conditions ESD performance depends on a variety of conditions. Contact Maxim for a reliability report that documents test methodology, and results. Human Body Model Figure 3 shows the Human Body Model. Figure 4 shows the current waveform it generates when discharged into a low impedance. This model consists of a 100pF capacitor charged to the ESD voltage of interest that is then discharged into the device through a 1.5kI resistor. Chip Information PROCESS: BiCMOS Package Information For the latest package outline information and land patterns (footprints), go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. PACKAGE TYPE PACKAGE CODE OUTLINE NO. LAND PATTERN NO. 8 TDFN-EP T822+2 21-0168 90-0065 10 ������������������������������������������������������������������������������������� Low-Power Headset Detectors with SEND/END Button Support REVISION NUMBER REVISION DATE 0 6/11 DESCRIPTION Initial release PAGES CHANGED — 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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2011 Maxim Integrated Products 11 Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX14579E/MAX14579AE Revision History