MAX7359 19-0850 Rev 4 6/10 2-Wire Interfaced Low-EMI Key Switch Controller/GPO General Description Features 2 The MAX7359 I C interfaced peripheral provides micro- Optional Key Release Detection on All Keys processors with management of up to 64 key switches. Monitor Up to 64 Keys Key codes are generated for each press and release of +1.62V to +3.6V Operation a key for easier implementation of multiple key entries. Autosleep and Autowake to Minimize Current Key inputs are monitored statically, not dynamically, to Consumption ensure low-EMI operation. The switches can be metallic or resistive (carbon) with up to 5k of resistance. Under 1A Sleep Current The MAX7359 features autosleep and autowake to fur- FIFO Queues Up to 16 Debounced Key Events ther minimize the power consumption of the device. Key Debounce Time User Configurable from 9ms The autosleep feature puts the device in a low-power to 40ms state (1A typ) after a sleep timeout period. The Low-EMI Design Uses Static Matrix Monitoring autowake feature configures the MAX7359 to return to Hardware Interrupt at the FIFO Level or at the End normal operating mode from sleep upon a key press. of Definable Time Period The key controller debounces and maintains a FIFO of Up to Seven Open-Drain Logic Outputs Available key-press and release events (including autorepeat, if Capable of Driving LEDs enabled). An interrupt (INT) output can be configured to 400kbps, 5.5V-Tolerant, 2-Wire Serial Interface alert key presses either as they occur, or at maximum rate. Selectable 2-Wire, Serial-Bus Timeout Any of the column drivers (COL2/PORT2COL7/PORT7) 2 or the INT, if not used, can function as a general-pur- Four I C Address Choices pose output (GPO). Small, 24-Pin TQFN Package (3.5mm x 3.5mm) , or 25-Pin WLP Package (2.31mm x 2.31mm) The MAX7359 is offered in small, 24-pin TQFN (3.5mm x 3.5mm) and 25-bump WLP (2.31mm x 2.31mm) pack- Ordering Information ages for cell phones, pocket PCs, and other portable consumer electronic applications. The MAX7359 oper- PART TEMP RANGE PIN-PACKAGE ates over the -40C to +85C temperature range. MAX7359ETG+ -40C to +85C 24 TQFN-EP* Applications MAX7359EWA+ -40C to +85C 25 WLP Cell Phones +Denotes a lead(Pb)-free/RoHS-compliant package. PDAs *EP = Exposed pad. Handheld Games Pin Configurations Portable Consumer Electronics TOP VIEW Typical Application Circuits 18 17 16 15 14 13 INT 19 12 COL1 INPUT V 20 11 COL2/PORT2 CC +1.62V TO +3.6V MAX7359 8 N.C. 21 10 COL5/PORT5 V CC COL SWITCH ARRAY, MAX7359 COL7/PORT7 22 9 COL6/PORT6 UP TO 64 8 ROW0 ROW7 23 8 SWITCHES ROW EP* ROW1 24 7 ROW6 SCL + SDA 1 2 34 56 INT AD0 GND TQFN (3.5mm x 3.5mm) *EP = EXPOSED PAD. Typical Application Circuits continued at end of data sheet. Pin Configurations continued at end of data sheet. Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com. EVALUATION KIT AVAILABLE ROW2 SCL ROW3 SDA COL3/PORT3 AD0 COL4/PORT4 GND ROW4 I.C. ROW5 COL02-Wire Interfaced Low-EMI Key Switch Controller/GPO ABSOLUTE MAXIMUM RATINGS (All voltages referenced to GND.) Junction-to-Case Thermal Resistance ( ) (Note 1) JC V ..........................................................................-0.3V to +4V 24-Pin TQFN.................................................................5.4C/W CC COL2/PORT2COL7/PORT7 ....................................-0.3V to +4V 25-Bump WLP ...............................................................17C/W SDA, SCL, AD0, INT.................................................-0.3V to +6V Junction-to-Ambient Thermal Resistance ( ) (Note 1) A J All Other Pins..............................................-0.3V to (V + 0.3V) 24-Pin TQFN...............................................................65.1C/W CC DC Current on COL2/PORT2COL7/PORT7 ......................25mA 25-Bump WLP ...............................................................53C/W GND Current .......................................................................80mA Operating Temperature Range (T to T ) .....-40C to +85C MIN MAX Continuous Power Dissipation (T = +70C) A Junction Temperature......................................................+150C 24-Pin TQFN (derate 15.4mW/C above +70C) ........1229mW Storage Temperature Range .............................-65C to +150C 25-Bump WLP (derate 19.2mW/C above +70C)......1194mW Lead Temperature (TQFN only, soldering, 10s) ..............+300C Soldering Temperature (reflow) .......................................+260C Note 1: Package thermal resistances were obtained using the method described in JEDEC specification JESD51-7, using a four- layer board. 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. ELECTRICAL CHARACTERISTICS (V = +1.62V to +3.6V, T = T to T , unless otherwise noted. Typical values are at V = +2.5V, T = +25C.) (Notes 2, 3) CC A MIN MAX CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Supply Voltage V 1.62 3.60 V CC All key switches open, oscillator running, 25 60 COL2COL7 configured as key switches Operating Supply Current I A CC (25 + N keys pressed 20 x N) Sleep-Mode Supply Current I 0.6 5 A SL POR 1.0 1.6 V POR Hysteresis PORHYST V rising 42 mV CC Key-Switch Source Current I 20 35 A KEY Key-Switch Source Voltage V Operating mode 0.42 0.55 V KEY Key-Switch Resistance R (Note 4) 5 k KEY Startup Time from Shutdown t 2 2.4 ms START Output Low Voltage V I = 10mA 0.2 V OLPORT SINK COL2/PORT2 to COL7/PORT7 INT Output V I = 10mA 0.5 V OLINT SINK Oscillator Frequency F 64 kHz OSC SERIAL-INTERFACE SPECIFICATIONS Serial Bus Timeout t With bus timeout enabled 10 40 ms OUT Input High Voltage 0.7 x V V IH SDA, SCL, AD0 V CC Input Low Voltage 0.3 x V V IL SDA, SCL, AD0 V CC Output Low Voltage SDA V I = 10mA 0.4 V OLPORT SINK Input Leakage Current V = 0V to +6V -1 +1 A CC 2 MAX7359