max97236 Maxim Integrated Products, Inc., max97236 Datasheet
max97236
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max97236 Summary of contents
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... Rev 0; 3/11 Audio Amplifier with Jack Detection General Description The MAX97236 is an audio amplifier with volume con- trol and microphone preamplifier intended for use in portable audio systems employing a headphone jack. The audio circuit is powered from a single, dual-mode charge pump, allowing the output signals to be ground referenced, and eliminating the need for large and expensive DC-blocking capacitors ...
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Audio Amplifier with Jack Detection ABSOLUTE MAXIMUM RATINGS V to PGND ..........................................................-0.3V to +2V DD MICVDD to PGND ................................................-0.3V to +5.5V PVDD to PGND ......................................... -0. PVSS to PGND ........................................................-2V to +0.3V GND to PGND ......................................................-0.1V to +0.1V ...
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Audio Amplifier with Jack Detection ELECTRICAL CHARACTERISTICS (continued 1.8V 3.0V MICVDD GND otherwise noted. See the Functional Diagram/Typical Application PARAMETER EXTCLK Input High Voltage EXTCLK Input Low Voltage EXTCLK Frequency Range EXTCLK ...
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Audio Amplifier with Jack Detection ELECTRICAL CHARACTERISTICS (continued 1.8V 3.0V MICVDD GND otherwise noted. See the Functional Diagram/Typical Application PARAMETER SYMBOL Maximum Capacitive Load Drive Power Consumption Charge-Pump Switch Threshold Click-and-Pop Level ...
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Audio Amplifier with Jack Detection ELECTRICAL CHARACTERISTICS (continued 1.8V 3.0V MICVDD GND otherwise noted. See the Functional Diagram/Typical Application PARAMETER Bias Power-Supply Rejection PSRR MICROPHONE PREAMPLIFIER MIC Preamp Gain Supply Current Consumption ...
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Audio Amplifier with Jack Detection TIMING CHARACTERISTICS ( unless otherwise noted. Typical values are MIN MAX PARAMETER Serial-Clock Frequency Bus Free Time Between STOP and START Conditions Hold Time ...
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Audio Amplifier with Jack Detection (V = 1.8V 3.0V MICVDD GND THD+N vs. OUTPUT POWER 100 R = 32I 100Hz 6kHz 0 1kHz ...
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... Typical Operating Characteristics (continued 1FF.) PGND FLY PVDD PVSS HEADPHONE AMPLIFIER TURN-OFF RESPONSE MAX97236 toc11 V SCL OUT 40µs/div CLASS H OPERATION MAX97236 toc14 V PVDD PVSS 100 20ms/div MICROPHONE PREAMPLIFIER THD+N vs. OUTPUT VOLTAGE 100 MIC GAIN = 12dB 1kHz 100Hz IN ...
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Audio Amplifier with Jack Detection (V = 1.8V 3.0V MICVDD GND MICROPHONE PREAMPLIFIER POWER-SUPPLY REJECTION RATIO vs. FREQUENCY 100 V = 200mV RIPPLE P ...
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... Left Headphone Output. Connect to the first ring of the four-pole jack. C1 PVSS Charge-Pump Negative Output. Bypass to PGND with 1FF. C2 SCL Serial-Clock Input C3 EXTCLK External System Clock Input. All internal digital clocks are derived from EXTCLK. 10 TOP VIEW MAX97236 INR INL PVDD GND GND IRQ MOUTN I.C. SCL ...
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Audio Amplifier with Jack Detection BUMP NAME C4 MOUTP Positive Microphone Output C5 RING1 Jack Input 2/Right Headphone Output. Connect to the first ring of the four-pole jack. D1 C1N Charge-Pump Flying Capacitor Negative Connection. Connect 1FF between C1N and ...
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... Headphone Volume Slewing Volume slewing breaks up large volume changes into the smallest available step size as it goes through each gain level between the initial and final volume setting. Volume MAX97236 IN_ Figure 2. Headphone Amplifier Signal Path 12 slewing also occurs at device turn-on and turn-off when enabled ...
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... Internal AC-coupling capacitors connect both the microphone output and also the MBIAS line to a differential amplifier, giving improved PSRR. MBIAS MAX97236 Figure 4. Microphone Preamplifier Simplified Schematic Table 1. Jack Detection and Configuration Load Limits PARAMETER Cable Shield Capacitance ...
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Audio Amplifier with Jack Detection Case special case that requires subsequent test- ing of the load pins while servicing the left audio load that has been found. In this case only, the status bits report that a ...
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... Figure 6. Single-Button, Passive Multibutton Hook Switch/Microphone Switch Timing MIC BIAS . DELAY Figure 9. The PRESS Bit Figure 5. Passive Single-Button Hook Switch MCSW PRESS IRQ AND REPORT VALUE t DELAY t DEB t t DELAY DEB MCSW PRESS IRQ AND REPORT VALUE t DELAY MAX97236 MCSW RELEASE IRQ t DELAY MCSW RELEASE IRQ 15 ...
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... The switched resistor and the microphone bias resistor set up a voltage-divider that creates a unique voltage. The on-chip ADC then encodes the voltage and reports to the system. MIC BIAS ADC MAX97236 Figure 7. Passive MBH PASSIVE MULTIBUTTON HEADSET (MBH): OTHER BUTTON, NORMAL SPEED, OR BUTTON HELD ADC CONVERT V BIAS ...
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Audio Amplifier with Jack Detection Removing the headphone jack slowly can cause a false trigger of the key switch encoder because the right speaker between RING1 and RING2 shorts between microphone bias and ground. The programmable delay time must be ...
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Audio Amplifier with Jack Detection Table 3. Register Map (continued) REGISTER B7 B6 Passive MBH PRESS RANGE Keyscan Data DC Test Slew Control State Forcing — — AC Test Control — — For Expansion — — For Expansion — — ...
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Audio Amplifier with Jack Detection Table 4. Configuration and Device Status Registers (continued) REGISTER BIT NAME 3 MIC_IN 2 JACKSW Status1 0x00 (Read Only) 1 MCSW 0 MBH 7 LINE_L 6 LINE_R 5 HP_L Status2 0x01 4 HP_R (Read Only) ...
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Audio Amplifier with Jack Detection Table 4. Configuration and Device Status Registers (continued) REGISTER BIT NAME 2 KEY Status2 0x01 (Read Only) 1 — 0 — 7 — 6 — 5 — 4 — 3 — 2 — Status3 0x02 ...
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Audio Amplifier with Jack Detection The Interrupt Mask registers control which status bits flag a system interrupt. Setting an interrupt mask bit causes IRQ to pull low whenever the target status bits set. The IRQ output resets to high, after ...
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Audio Amplifier with Jack Detection The Headphone Volume registers independently control and report the gain of the left and right headphone amplifiers. Set B7 in Register 0x04 to have the right-channel gain track the left-channel gain. Table 6. Headphone Volume ...
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Audio Amplifier with Jack Detection The Microphone Bias Control and Gain register controls which microphone bias voltage and bias resistors are used as well as the microphone amplifier gain. Table 7. Microphone Bias and Gain Register REGISTER BIT NAME 7 ...
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Audio Amplifier with Jack Detection The Keyscan Clock Divider register sets the clock frequency that is used for the conversion clock for the keyscan 1kHz generator. Table 9. Keyscan Clock Divider Registers REGISTER BIT Keyscan 4 Clock ...
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Audio Amplifier with Jack Detection The Keyscan Delay register sets the timeout that the microphone button press is masked from the system. At the end of the delay time, the IC checks to see if a microphone is still present. ...
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Audio Amplifier with Jack Detection The ramp test slew control programs the period of the jack configuration algorithm’s ramp test. Slow slew rates ensure test inaudibility, but increase test time to complete the configuration algorithm. Table 14. Ramp Test Slew ...
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Audio Amplifier with Jack Detection Table 15. Load State Forcing (continued) REGISTER BIT NAME 4 3 State Forcing STATE 0x19 DESCRIPTION State Value Bits 0b4–0b0 programs the configuration of the IC. The columns show all the possible ...
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Audio Amplifier with Jack Detection The Jack Detect Test Hardware Settings register programs the amplitude and width of the pulse used in the jack detec- tion tests and jack insertion algorithm. Table 16. Jack Detect Test Hardware Settings REGISTER BIT ...
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Audio Amplifier with Jack Detection Table 17. Enable Registers (continued) REGISTER BIT NAME 5 4 MIC_BIAS 3 MIC_AMP Enable1 0x1D LFTEN Enable2 0x1E 6 RGHEN — — Microphone Bias Enable/Status Set MIC_BIAS to enable the microphone ...
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Audio Amplifier with Jack Detection Table 17. Enable Registers (continued) REGISTER BIT NAME 5 VSEN 4 ZDEN 3 FAST Enable2 0x1E 2 THRH 1 AUTO 0 30 DESCRIPTION Volume Adjustment Slewing Volume changes are smoothed by stepping through intermediate steps. ...
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Audio Amplifier with Jack Detection SDA t SU,DAT t LOW SCL t HIGH t HD,STA t R START CONDITION 2 Figure 10 Interface Timing Diagram Serial Interface The IC features C/SMBusK-compatible, 2-wire ...
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... The second byte transmitted from the master configures the IC’s internal register address pointer. The pointer tells the IC where to write the next byte of data. An acknowledge pulse is sent by the IC upon receipt of the address pointer data. ACKNOWLEDGE FROM MAX97236 0 A REGISTER ADDRESS ACKNOWLEDGE FROM ...
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... IC. ACKNOWLEDGE FROM ACKNOWLEDGE FROM MAX97236 REGISTER ADDRESS A Sr SLAVE ADDRESS REPEATED START ACKNOWLEDGE FROM ACKNOWLEDGE FROM MAX97236 MAX97236 A Sr SLAVE ADDRESS REPEATED START Figure 15 NOT ACKNOWLEDGE FROM MASTER MAX97236 1 A DATA BYTE A R/W ...
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Audio Amplifier with Jack Detection Applications Information The power modes of the IC are controlled by the SHDN bit. The three power modes include detection, normal operating, and standby. Detection mode occurs when no jack has been plugged in, SHDN ...
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Audio Amplifier with Jack Detection Power-Up, AUTO = 0x02: 1) Wait for JKIN to set. 2) Detection runs automatically, so wait for DDONE to set. 3) Read the Status registers to find out what was detected. 4) The IC is ...
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Audio Amplifier with Jack Detection Component Selection and Layout Charge-Pump Capacitors The charge pump requires three capacitors: PVDD, PVSS, and the flying capacitor between C1N and C1P recommended that these all remain the same value. Table 19. Recommended ...
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... Audio Amplifier with Jack Detection Functional Diagram/Typical Application Circuit INL PVDD V DD C1P CHARGE C1N PUMP PVSS INR MAX97236 MOUTP MOUTN MIC SDA MIC BIAS SENSE SELECT INTERFACE SCL HP VOL AND CONTROL CONTROL IRQ EXTCLK 1.8V 2.4V TO 3.6V V MVDD DD PVDD PVSS GND SENSE ...
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Audio Amplifier with Jack Detection For the latest package outline information and land patterns 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, ...
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... 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 © Revision History DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc. PAGES CHANGED — 39 ...