EVALUATION KIT AVAILABLE MAX7370 8 x 8 Key-Switch Controller and LED Driver/GPIOs 2 with I C Interface and High Level of ESD Protection General Description Features 2 S Monitors Up to 64 Keys The MAX7370 I C-interfaced peripheral provides micro- processors with management of up to 64 key switches, S Integrated High-ESD Protection with optional GPIO and PWM-controlled LED drivers. 8kV IEC 61000-4-2 Contact Discharge The key-switch drivers interface with metallic or resistive 15kV IEC 61000-4-2 Air-Gap Discharge switches with on-resistances up to 5kI. Key inputs are S Keyscan Uses Static Matrix Monitoring for monitored statically, not dynamically, to ensure low-EMI Low-EMI Operation operation. The IC features autosleep and autowake S Four LED Driver Pins on COL7COL4 modes to further minimize the power consumption of S 5V Tolerant, Open-Drain I/O Ports Capable of the device. The autosleep feature puts the device in a Constant-Current LED Drive low-power state (1A typ) after a timeout period. The S 256-Step PWM Individual LED Intensity-Control autowake feature configures the device to return to Accuracy normal operating mode from sleep upon a keypress. S Individual LED Blink Rates and Common LED The key controller debounces and maintains a FIFO Fade In/Out Rates from 256ms to 4096ms buffer of keypress and release events (including auto- repeat, if enabled). An interrupt (INT) output can be S FIFO Queues Up to 16 Debounced Key Events configured to alert keypresses, as they occur, or at the S User-Configurable Keypress and Release maximum rate. Debounce Time (2ms to 32ms) The same index rows and columns in the device can be S Key-Switch Interrupt (INT) on Each Debounced used as a direct logic-level translator. Event/FIFO Level, or End-of-Definable Time Period If the device is not used for key-switch control, all S 1.62V to 3.6V Operating Supply Voltage keyboard pins can be used as GPIOs. Each GPIO can S Individually Programmable GPIOs to Two Logic be programmed to one of the two externally applied Levels logic voltage levels. Four column ports (COL7COL4) S 8-Channel Individual Programmable Level can also be configured as LED drivers that feature Translators constant-current and PWM intensity control. The maximum S Provides Optional GPIOs on all ROW and COL constant-current level for each open-drain LED port is Pins 20mA. The intensity of the LED on each open-drain port S Supports Hot Insertion can be individually adjusted through a 256-step PWM control. 2 S 400kbps, 5.5V Tolerant I C Serial Interface with Selectable Bus Timeout The device is offered in a 24-pin (3.5mm x 3.5mm) TQFN Ordering Information appears at end of data sheet. package with an exposed pad, and small 25-bump (2.159mm x 2.159mm) wafer-level package (WLP) for Typical Operating Circuit cell phones, pocket PCs, and other portable consumer electronic applications. +1.8V +2.6V +5V The device operates over the -40C to +85C extended temperature range. V V CC LA Applications MAX7370 COL4 Cell Phones COL5 INT COL6 I/O Notebooks MCU SDA COL7 I/O SCL PDAs 8 AD0 ROW 0:7 Handheld Games 4 COL 0:3 Portable Consumer Electronics GND For related parts and recommended products to use with this part, 32 KEYS refer to www.maximintegrated.com/MAX7370.related. For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxims website at www.maximintegrated.com. 19-5950 Rev 2 5/15MAX7370 8 x 8 Key-Switch Controller and LED Driver/GPIOs 2 with I C Interface and High Level of ESD Protection ABSOLUTE MAXIMUM RATINGS V , V to GND ....................................................-0.3V to +4V Continuous Power Dissipation (T = +70C) CC LA A COL3COL0, ROW7ROW0 to GND ....... -0.3V to (V + 0.3V) 24-Pin TQFN (derate 15.4mW/C above +70C) ...... 1229mW CC COL7COL4 to GND ...............................................-0.3V to +6V 25-Bump WLP (derate 19.2mW/C above +70C) ......850mW SDA, SCL, AD0, INT to GND ..................................-0.3V to +6V Operating Temperature Range .......................... -40C to +85C V to V ...........................................................-0.3V to +2.3V Junction Temperature .....................................................+150C LA CC DC Current on COL7COL4 to GND .................................25mA Storage Temperature Range ............................ -65C to +150C DC Current on COL3COL0, ROW7ROW0 to GND ...........7mA Lead Temperature (TQFN) (soldering, 10s) ...................+300C V , V , GND Current .....................................................80mA Soldering Temperature (reflow) ......................................+260C CC LA DC Current V , V to COL3COL0, ROW7ROW0 .........5mA CC LA Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only, and functional opera- tion 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. PACKAGE THERMAL CHARACTERISTICS (Note 1) 24 TQFN 25 WLP Junction-to-Ambient Thermal Resistance (B ) .........65.1C/W Junction-to-Ambient Thermal Resistance (B ) ...........52C/W JA JA Junction-to-Case Thermal Resistance (B ) ................5.4C/W JC 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.maximintegrated.com/thermal-tutorial. ELECTRICAL CHARACTERISTICS (V = 1.62V to 3.6V, T = -40NC to +85NC, unless otherwise noted. Typical values are at V = 3.3V, T = +25NC.) (Notes 2, 3) CC A CC A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Operating Supply Voltage V 1.62 3.3 3.6 V CC Second Logic Supply V V 3.3 3.6 V LA CC All key switches open, oscillator 50 65 running Operating Supply Current I FA CC N keys pressed 50 + 28 O N Sleep-Mode Supply Current I Not using GPO or LED configuration 1.8 3 FA SL POR Threshold V 1.2 V POR KEY-SWITCH SPECIFICATIONS Key-Switch Source Current I 28 40 FA KEY Key-Switch Source Voltage V 0.45 0.5 V KEY Key-Switch Resistance R (Note 4) 5 kI KEY Startup Time from Sleep t 2 2.7 ms START GPIO SPECIFICATIONS External Supply Voltage V 5 V LED COL7COL4 (LED Drivers) V = 3.3V, V = 1V, T = +25NC, CC OL A LED Port-to-Port Sink Current Variation Q1.5 Q2.4 % 10mA output mode Maxim Integrated 2