MAX9940 19-4168 Rev 0 2/09 Signal-Line Overvoltage Protector for Low-Voltage Devices General Description Features The MAX9940 signal-line overvoltage protector for low- 28V Protection on EXT voltage digital communication ports provides protection Extended ESD Protection against high-voltage faults and ESD strikes. The 4kV IEC 61000-4 Contact on EXT MAX9940 is especially useful for sensitive communica- tion protocols such as Maxim 1-Wire that cannot +2.2V to +5.5V Supply Voltage Range afford standard means of fault protection, such as large 13A Quiescent Supply Current series resistors or large line capacitances. The MAX9940 operates from a single supply voltage of 60ns Fault Reaction Time +2.2V to +5.5V and consumes only 13A of quiescent Small, 5-Pin SC70 supply current. The EXT port is protected up to 28V. The device features a reaction time of 60ns for fast -40C to +125C Temperature Range action during fault conditions and operates over the -40C to +125C automotive temperature range. Applications Ordering Information Notebook Computers PIN- TOP PART TEMP RANGE Portable Devices PACKAGE MARK MAX9940AXK+ -40C to +125C 5 SC70 ATC Industrial Equipment +Denotes a lead(Pb)-free/RoHS-compliant package. 1-Wire is a registered trademark of Maxim Integrated Products, Inc. Block Diagram/Typical Application Circuit ADAPTER NOTEBOOK V = 3.3V DD LOAD NOTEBOOK BATTERY CHARGER ENABLE V CC MAX9940 MICROCONTROLLER + 2k PROTECTION - 20V CIRCUIT 1-Wire DEVICE DATA EXT Rx Rx N INT P Tx Tx GND 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.Signal-Line Overvoltage Protector for Low-Voltage Devices ABSOLUTE MAXIMUM RATINGS (All voltages with respect to GND.) Continuous Power Dissipation (T = +70C) A V ...........................................................................-0.3V to +6V 5-Pin SC70 (derate 3.1mW/C above +70C)..............245mW CC INT............................................................................-0.3V to +6V Operating Temperature Range .........................-40C to +125C EXT .........................................................................-0.3V to +30V Junction Temperature......................................................+150C Continuous Input Current into Any Terminal.....................20mA Storage Temperature Range .............................-65C to +150C 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 = +3.3V, R = 2k to V , V = 3.3V, T = T to T , unless otherwise noted. Typical values are at CC INT PULLUP DD DD A MIN MAX T = +25C.) (Note 1) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS POWER SUPPLY Power-Supply Voltage V 2.2 5.5 V CC Quiescent Supply Current I V = 0 13 21 A CC INT DC CHARACTERISTICS INT Voltage Range V 0 5.5 V INT EXT Voltage Range V (Note 2) -0.7 +28 V EXT V + V + V + CC CC CC EXT Rising Threshold V V THR 0.19 0.26 0.30 V + V + V + CC CC CC EXT Falling Threshold V V THF 0.09 0.13 0.16 SWITCH CHARACTERISTICS On-Resistance R 0 < V < V , I = 10mA 43.5 77.5 ON EXT CC EXT On-Capacitance C Capacitance to GND 38 pF ON INT Off-Capacitance C Capacitance to GND 27 pF OFF INT Normal Operation Leakage 0 < V < V , V = 5.5V 3 4.2 A INT CC CC Current (to GND) EXT Normal Operation Leakage 0 < V < V , V = 5.5V 3 5 A EXT CC CC Current (to GND) INT Fault Leakage Current V = 3.3V, V = 28V 2 10 nA INT EXT EXT Fault Leakage Current V = 3.3V, V = 28V 341 510 A INT EXT V = V = 0, 2.2V < V < 5.5V, CC DD DD 38 70 A INT Shutdown Leakage Current R = 2k to V INT PULLUP DD (to GND) V = V = 0 1 nA CC DD AC CHARACTERISTICS Power-Up Delay Time t 500 s PUP Fault, V = 10V, R = 200 98 200 EXT INT PULLUP Fault Reaction Time t ns OFF Fault, V = 16V, R = 200 60 EXT INT PULLUP Fault Recovery Time t Fault removed, V < V - 0.8V 271 375 ns ON EXT CC Note 1: All devices are 100% production tested at T = +25C. Specifications over temperature limits are guaranteed by design. A Note 2: Minimum EXT voltage of -0.7V is allowed only with a maximum drawn current of 20mA. 2 MAX9940