MAX7349AEG-T Maxim Integrated, MAX7349AEG-T Datasheet
MAX7349AEG-T
Related parts for MAX7349AEG-T
MAX7349AEG-T Summary of contents
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... Easy Automatic Single-Tone and Dual-Tone Alarm Sound Generation ♦ Four I 2 ♦ Selectable 2-Wire Serial Bus Timeout Applications ♦ Under 10µA Shutdown Current PART MAX7347AEE+ MAX7347ATE+ MAX7348AEP+ MAX7349AEG+ 8 SWITCH MAX7349ATG+ ARRAY Denotes lead-free package SWITCHES * EP = Exposed paddle. PIEZO TRANSDUCER ...
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Interfaced Low-EMI Key Switch and Sounder Controllers ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) V+ ............................................................................-0.3V to +4V COL2/PORT2–COL7/PORT7 ....................................-0.3V to +4V SDA, SCL, AD0, ALERT, INT ....................................-0.3V to +6V All Other Pins................................................-0.3V to (V+ + 0.3V) DC ...
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Interfaced Low-EMI Key Switch TIMING CHARACTERISTICS (V+ = 2.4V to 3.6V unless otherwise noted. Typical values are 3.3V MIN MAX PARAMETER SYMBOL Input Capacitance (SCL, ...
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Interfaced Low-EMI Key Switch and Sounder Controllers (V+ = 3.3V +25°C, unless otherwise noted. Supply range for V+ is 2.4V to 3.6V. Temperature range is -40°C to +125°C.) A GPO OUTPUT LOW VOLTAGE vs. SINK CURRENT 300 ...
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Interfaced Low-EMI Key Switch PIN MAX7347 MAX7347 MAX7349 MAX7348 (QSOP) (TQFN) (QSOP ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 1. Product Features Table MAXIMUM PACKAGE- PART KEY PINS SWITCHES MAX7349 24 64 MAX7348 20 40 MAX7347 16 24 too many interrupts. The key-switch status can be checked at any time ...
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Interfaced Low-EMI Key Switch *MAX7348 AND MAX7349 ONLY. **MAX7349 ONLY. COL7/PORT7** COL6/PORT6** COL5/PORT5** COL4/PORT4* COL3/PORT3* COL2/PORT2 COL1 COL0 ROW0 ROW1 ROW2 ROW3 ROW4 ROW5 ROW6 ROW7 Figure 1. Keys Order STOP (P) condition by transitioning SDA from low to ...
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Interfaced Low-EMI Key Switch and Sounder Controllers SDA t SU, DAT t LOW t SCL HIGH t HD, STA t R START CONDITION Figure 2. 2-Wire Serial Interface Timing Details SDA SCL S START CONDITION Figure 3. Start and ...
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Interfaced Low-EMI Key Switch Table 2. Key-Switch Mapping PIN COL0 COL1 ROW0 KEY 0 KEY 8 ROW1 KEY 1 KEY 9 ROW2 KEY 2 KEY 10 ROW3 KEY 3 KEY 11 ROW4 KEY 4 KEY 12 ROW5 KEY 5 ...
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Interfaced Low-EMI Key Switch and Sounder Controllers START CONDITION SCL SDA BY TRANSMITTER SDA BY RECEIVER S Figure 5. Acknowledge 0 1 SDA MSB SCL Figure 6. Slave Address The MAX7347/MAX7348/MAX7349 feature a 20ms mini- mum bus timeout on ...
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Interfaced Low-EMI Key Switch COMMAND BYTE IS STORED ON RECEIPT OF ACKNOWLEDGE FROM MAX7347/MAX7348/MAX7349 S SLAVE ADDRESS Figure 7. Command Byte Received ACKNOWLEDGE FROM MAX7347/MAX7348/MAX7349 S SLAVE ADDRESS 0 R/W Figure 8. Command and Single Data Byte Received Message ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 5. Key-Scan Power-Up Configuration REGISTER POWER-UP CONDITION FUNCTION Keys FIFO Empty Debounce Ports 2–7 are enabled; debounce time is 39ms Autorepeat Autorepeat is disabled INT is a port, not an interrupt ...
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Interfaced Low-EMI Key Switch Table 7. Key-Scan Register Address Map REGISTER FUNCTION D15 D14 Keys FIFO 0 Debounce 0 Autorepeat 0 Interrupt 0 Configuration 0 Ports 0 Key Sound 0 Alert Sound 0 Table 8. Keys FIFO Register Format ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 9. Debounce Register Format REGISTER DEBOUNCE REGISTER Debounce time is 9ms Debounce time is 10ms Debounce time is 11ms Debounce time is 12ms All the way through to Debounce time is ...
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Interfaced Low-EMI Key Switch ranging from 8 debounce cycles to 128 debounce cycles (Table 10). Bits D4 through D6 specify the autorepeat rate or frequency ranging from debounce cycles. Bit D7 specifies whether the auto-repeat function ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 10. Autorepeat Register Format REGISTER AUTOREPEAT REGISTER Autorepeat is disabled Autorepeat is enabled Key-switch autorepeat delay is 8 debounce cycles Key-switch autorepeat delay is 16 debounce cycles Key-switch autorepeat delay is ...
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Interfaced Low-EMI Key Switch Table 11. Interrupt Register Format REGISTER INTERRUPT REGISTER Current INT is due to key-scan event(s) Current INT is due to alert event Current INT is due to both key-scan event(s) and alert event INT has ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 12. Configuration Register Format REGISTER CODE (hex) CONFIGURATION REGISTER Serial interface bus timeout enabled Serial interface bus timeout disabled No active sounder output Active sounder output set by serial interface Active ...
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Interfaced Low-EMI Key Switch Table 12. Configuration Register Format (continued) REGISTER CODE (hex) CONFIGURATION REGISTER Shutdown mode; key-scan and sounder timing are disabled, interrupts disabled, but alert input can be read and port outputs (as selected) can be changed ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 13. Ports Register Format (continued) ADDRESS REGISTER CODE (hex) PORTS REGISTER 0x05 Clear port 7 low 0x05 Set port 7 high (high 0x05 impedance) Clear INT port low; this setting is ...
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Interfaced Low-EMI Key Switch Table 15. Alert Sound Register Format REGISTER This 8-bit value is passed to sounder controller on the falling edge of the alert input; these 7 bits define duration and frequency only; sounder command bit D0 ...
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Interfaced Low-EMI Key Switch and Sounder Controllers Table 16. Sounder Register Format (continued) REGISTER SOUNDER REGISTER Sounder output active low for sound duration; queue cleared Sounder output active high for sound duration; queue cleared Sound frequency is 523.25Hz, idles ...
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Interfaced Low-EMI Key Switch Sounder Operation When an alert sound or key sound is happening, the user cannot write to the sounder. The MAX7347/MAX7348/ MAX7349 do not acknowledge a write to the sounder I address. However, a read from ...
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Interfaced Low-EMI Key Switch and Sounder Controllers REGULAR KEY-PRESS EVENT KEY-SWITCH MATRIX Figure 10. Ghost-Key Phenomenon 0.22μF 2.61kΩ SOUNDER OUTPUT 68nF Figure 12. Third-Order Chebyshev Lowpass Filter and Output Stage Audio Transducers The sounder output is designed to drive ...
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Interfaced Low-EMI Key Switch 3.3V 3.3V 3.3V V+ MAX7348 COL3/PORT3 COL4/PORT4 AD0 5V V+ SCL SCL SDA SDA INT INT SOUNDER GND PIEZOELECTRIC TRANSDUCER ______________________________________________________________________________________ and Sounder Controllers Typical Application Circuit COL2/PORT2 COL1 COL0 ROW0 ROW1 ROW2 ROW3 ROW4 ...
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Interfaced Low-EMI Key Switch and Sounder Controllers TOP VIEW + ROW0 1 ROW1 2 ROW2 3 MAX7347 ROW3 4 ROW4 5 ROW5 6 ROW6 7 ROW7 8 QSOP TOP VIEW INT MAX7347 ROW0 ...
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Interfaced Low-EMI Key Switch (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) ______________________________________________________________________________________ and Sounder Controllers Package Information PACKAGE OUTLINE, QSOP .150", .025" LEAD ...
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Interfaced Low-EMI Key Switch and Sounder Controllers (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information www.maxim-ic.com/packages.) 28 ______________________________________________________________________________________ Package Information (continued) PACKAGE OUTLINE, 12, 16, ...
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... 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 ____________________ 29 © 2007 Maxim Integrated Products ...