MAX7359 Maxim, MAX7359 Datasheet
MAX7359
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MAX7359 Summary of contents
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... Any of the column drivers (COL2/PORT2–COL7/PORT7) or the INT, if not used, can function as a general-pur- pose output (GPO). The MAX7359 is offered in small, 24-pin TQFN (3.5mm x 3.5mm) and 25-bump WLP (2.31mm x 2.31mm) pack- ages for cell phones, pocket PCs, and other portable consumer electronic applications. The MAX7359 oper- ates over the -40° ...
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... For detailed information on package thermal considerations, refer to www.maxim-ic.com/thermal-tutorial. 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 ...
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I C TIMING CHARACTERISTICS (V = +1.62V to +3.6V MIN PARAMETER SYMBOL Input Capacitance (SCL, SDA, AD0) SCL Serial-Clock Frequency Bus Free Time Between a STOP and a START Condition Hold Time ...
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Interfaced Low-EMI Key Switch Controller/GPO (V = +2.5V +25°C, unless otherwise noted GPO PORT OUTPUT LOW VOLTAGE vs. SINK CURRENT 300 V = +2.4V CC 250 T = +85°C A 200 150 100 T = ...
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... MAX7359 64kHz OSCILLATOR INT CONTROL SDA REGISTERS SCL FIFO INTERFACE BUS POR TIMEOUT *GPO _______________________________________________________________________________________ 2-Wire Interfaced Low-EMI Key Switch Controller/GPO Functional Block Diagram COLUMN ENABLE CURRENT GPO ENABLE SOURCE COLUMN CURRENT DETECT DRIVES KEY SCAN OPEN- ROW ENABLE DRAIN ...
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... The MAX7359 can be configured to enter sleep mode after a programmable time following a key event. The FIFO content is maintained during sleep mode and can be read in sleep mode. The MAX7359 does not enter autosleep when a key is held down. The autowake feature takes the MAX7359 out of sleep mode following a key- press event ...
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... The configuration register controls the I feature, enables key release detection, enables autowake, and determines how INT should be deasserted. By writing to bit D7, you can put the MAX7359 into sleep mode or operating mode, however, autosleep and autowake, when enabled, also change the status of this bit (Table 4). ...
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Interfaced Low-EMI Key Switch Controller/GPO Table 3. Keys FIFO Register Format (0x00) SPECIAL FUNCTION The key number indicated by D5: key event always for a key press of key 62 and key 63. When D7 ...
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Table 4. Configuration Register Format (0x01) REGISTER BIT DESCRIPTION D7 Sleep D6 Reserved D5 INTERRUPT D4 Reserved D3 Key release enable D2 Reserved D1 Wakeup D0 Timeout enable _______________________________________________________________________________________ 2-Wire Interfaced Low-EMI Key Switch Controller/GPO VALUE FUNCTION ...
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Interfaced Low-EMI Key Switch Controller/GPO Debounce Register (0x02) The debounce register sets the time for each debounce cycle, as well as setting whether the GPO ports are enabled or disabled. Bits D0 through D4 set the debounce time in ...
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... GPOs, and a read from this register returns the values stored in the register (Table 7). Autorepeat Register (0x05) The MAX7359 autorepeat feature notifies the host that at least one key has been pressed for a continuous period of time. The autorepeat register enables or disables this ...
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Interfaced Low-EMI Key Switch Controller/GPO Table 7. Ports Register Format (0x04) REGISTER BIT DESCRIPTION D7 PORT 7 Control D6 PORT 6 Control D5 PORT 5 Control D4 PORT 4 Control D3 PORT 3 Control D2 PORT 2 Control INT ...
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... SCL output. Each transmission consists of a START (S) condition (Figure 2) sent by a master, followed by the MAX7359 7- bit slave address plus R/W bit, a register address byte more data bytes, and finally a STOP (P) condition. Autowake Both SCL and SDA remain high when the interface is not busy ...
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Interfaced Low-EMI Key Switch Controller/GPO SDA t SU, DAT t LOW t SCL HIGH t HD, STA t R START CONDITION Figure 1. 2-Wire Serial Interface Timing Details SDA SCL S START CONDITION Figure 2. START and STOP Conditions ...
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... Bus timeout operates by causing the MAX7359 to internally terminate a serial transaction, either read or write, if SCL low exceeds 20ms. After a bus timeout, the MAX7359 waits for a valid Slave Addresses START condition before responding to a consecutive transmission. This feature can be enabled or disabled under user control by writing to the configuration register (Table 4) ...
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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 MAX7359 written by the next byte, if received STOP condition is detected after the com- mand byte is received, the MAX7359 takes no further action (Figure 6) beyond storing the command byte ...
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... Bypass the power supply to GND with a 0.047µF or higher ceramic capacitor as close as possi- ble to the device. The MAX7359 is designed to be insensitive to resis- tance either in the key switches or the switch routing to and from the appropriate COLx and ROWx up to 5kΩ. ...
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... Interfaced Low-EMI Key Switch Controller/GPO REGULAR KEY-PRESS EVENT KEY-SWITCH MATRIX Figure 9. Ghost-Key Phenomenon +3.3V +3.3V +1. COL6/PORT6 COL7/PORT7 AD0 MAX7359 + SCL SCL µC SDA SDA INT INT GND GND 18 ______________________________________________________________________________________ GHOST-KEY EVENT KEY-SWITCH MATRIX Figure 10. Valid Three-Key Combinations Typical Application Circuits (continued) ...
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... Pin Configurations (continued) TOP VIEW (BUMPS ON BOTTOM) MAX7359 COL3/ ROW2 ROW3 ROW4 PORT3 A COL4/ ROW1 ROW0 ROW7 PORT4 B COL7/ COL5/ N.C. N.C. PORT7 PORT5 C V SCL GND CC D INT SDA AD0 E WLP (2.31mm × 2.31mm) ______________________________________________________________________________________ 2-Wire Interfaced Low-EMI Key Switch Controller/GPO ...
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... Electrical Characteristics 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. 20 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © ...