MAX7347 MAXIM [Maxim Integrated Products], MAX7347 Datasheet
MAX7347
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MAX7347 Summary of contents
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... The output can also be pro- grammed to be high or low for the sound duration to operate an electronic sounder, relay, or lamp. The MAX7347 is offered in 16-pin QSOP and TQFN packages. The MAX7348 is offered in a 20-pin QSOP package. The MAX7349 is available in 24-pin QSOP and TQFN packages. The MAX7347/MAX7348/MAX7349 operate over the -40° ...
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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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... T = +125° -40° 2.4 2.6 2.8 3.0 3.2 3.4 SUPPLY VOLTAGE (V) SOUNDER OUTPUT MAX7347 toc07 3V V SOUNDER 1V/div 0V 200μs/div 4 _______________________________________________________________________________________ Typical Operating Characteristics GPO OUTPUT LOW VOLTAGE vs. SINK CURRENT 300 250 200 T = +125°C A 150 100 T = -40°C ...
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... key switches can be monitored and debounced with optional autorepeat, and the key events are presented in an eight-deep FIFO. Key-switch functionality can be traded to provide up to one (MAX7347), three (MAX7348), or six (MAX7349) open-drain logic outputs. (Table 1). _______________________________________________________________________________________ and Sounder Controllers ...
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... SCL output. Each transmission consists of a START condition (Figure 3) sent by a master, followed by the MAX7347/ MAX7348/MAX7349 7-bit slave address plus R/W bit, a register address byte more data bytes, and finally a STOP condition. ...
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... When the master is transmitting to the MAX7347/MAX7348/ MAX7349, the MAX7347/MAX7348/MAX7349 generate the acknowledge bit because the MAX7347/MAX7348/ MAX7349 are the recipients. When the MAX7347/ Acknowledge MAX7348/MAX7349 are transmitting to the master, the master generates the acknowledge bit because the master is the recipient ...
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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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... GND, V+, SDA, or SCL, giving four possible slave address pairs, allowing up to four MAX7348/ MAX7349 devices to share the bus. Only one MAX7347 can share the bus. The MAX7347 AD0 input is internally connected to GND. The MAX7347/MAX7348/MAX7349 monitor the bus continuously, waiting for a START condition followed by its slave address ...
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... R/W bit set to zero, followed by at least 1 byte of information. The first byte of information is the command byte. The command byte determines which register of the MAX7347/MAX7348/MAX7349 written by the next byte, if received STOP condition is detected after the command byte is received, then the MAX7347/MAX7348 /MAX7349 take no further action (Figure 7) beyond stor- ing the command byte ...
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... If the MAX7347/MAX7348/MAX7349 are operated wire interface with multiple masters, a master reading the MAX7347/MAX7348/MAX7349 should use a repeated start between the write that sets the MAX7347/MAX7348/ MAX7349s’ address pointer, and the read(s) that takes the data from the location(s). This is because it is possi- ble for master 2 to take over the bus after master 1 has set up the MAX7347/MAX7348/MAX7349s’ ...
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... REGISTER DATA ACKNOWLEDGE FROM MAX7347/MAX7348/MAX7349 DATA BYTE N BYTES AUTOINCREMENT COMMAND BYTE ADDRESS ...
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... Reading the key-scan FIFO clears the INT. INT is only reasserted by a key event after the FIFO has been emptied by read(s). Command Address Autoincrementing Address autoincrementing allows the MAX7347/ MAX7348/MAX7349 to be configured with fewer trans- missions by minimizing the number of times the com- mand address needs to be sent ...
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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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... The MAX7347/MAX7348/MAX7349 may be taken out of shutdown mode and put into operating mode by setting bit D7 in the configuration register (Table 12). The key- scan and sounder controller FIFOs are cleared, and key monitoring starts ...
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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 15 ROW1 TQFN-EP *EP = EXPOSED PADDLE TOP VIEW + ROW0 1 ROW1 2 ROW2 3 ROW3 4 MAX7348 COL3/PORT3 5 COL4/PORT4 6 ROW4 7 ROW5 8 ...
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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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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.) Revision History Pages changed at Rev 23, 29 Maxim ...