MAX1922 19-2254 Rev 3 4/09 1A Current-Limited Switch for 2 USB Ports General Description Features The MAX1922 current-limited 70m switch with built-in Accurate Current Limit (1.4A min, 2.1A max) fault blanking provides an accurate, preset 1.4A to 2.1A 10ms Internal OC Blanking Timeout current limit, making it ideal for dual USB applications. Its low quiescent supply current (16A) and standby OC Blanking During Power-Up current (1A) conserve battery power in portable appli- 125m (max) High-Side MOSFET cations. The MAX1922 operates with inputs from 2.7V to 5.5V, making it ideal for both 3V and 5V systems. Short-Circuit and Thermal Protection with Overcurrent Logic Output An overcurrent signal (OC) notifies the microprocessor that the internal current limit has been reached. A 10ms Undervoltage Lockout overcurrent-blanking feature allows momentary faults 16A Quiescent Supply Current (such as those caused when hot-swapping into a capacitive load) to be ignored, thus preventing false 1A (max) Standby Supply Current alarms to the host system. This blanking also prevents 2.7V to 5.5V Supply Range an OC signal from being issued when the device is powering up. UL Recognized: UL E211395 The MAX1922 has several safety features to ensure that the USB port is protected. Built-in thermal-overload pro- tection limits power dissipation and junction tempera- ture. The device also has accurate internal current- limiting circuitry to protect the input supply against Ordering Information overload. TOP PIN- The MAX1922 is offered in a space-saving 8-pin SO PART TEMP RANGE MARK PACKAGE package and a 10-pin TDFN package and operates over the extended (-40C to +85C) temperature range. MAX1922ESA+ -40C to +85C 8 SO MAX1922ETB+ -40C to +85C 10 TDFN-EP* AQQ Applications *EP = Exposed paddle. Notebook Computers +Denotes a lead(Pb)-free/RoHS-compliant package. USB Ports USB Hubs Docking Stations Pin Configurations Typical Operating Circuit TOP VIEW INPUT 2.7V TO 5.5V IN OUT OUTPUT GND 1 8 OUT MAX1922 IN 2 7 OUT MAX1922 IN 3 6 OUT OC EN 4 5 OC OFF EN ON SO GND 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.1A Current-Limited Switch for 2 USB Ports ABSOLUTE MAXIMUM RATINGS IN, EN, OC to GND...................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A 8-Pin SO (derate 5.88mW/C above +70C)................471mW OUT to GND ................................................-0.3V to (V + 0.3V) IN Maximum Switch Current.........................2.3A (internally limited) 10-Pin TDFN (derate 18.5mW/C above +70C) .......1481mW Operating Temperature Range (extended).........-40C to +85C OUT Short-Circuit to GND..........................................Continuous Storage Temperature Range .............................-65C to +150C Lead Temperature (soldering, 10s) .................................+300C 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 = 5V, T = 0C to +85C, unless otherwise noted. Typical values are at T = +25C.) IN A A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS OPERATING CONDITION Input Voltage V 2.7 5.5 V IN POWER SWITCH T = +25C V = 4.4V to 5.5V 70 100 A IN Switch Static Drain-Source On- R V = 4.4V to 5.5V 125 m DS(ON) IN State Resistance T = 0C to +85C A V = 3V 72 150 IN Switch Turn-On Time t I = 400mA 80 200 s ON LOAD Switch Turn-Off Time t I = 400mA 3 6 20 s OFF LOAD ENABLE INPUT (EN) V = 2.7V to 3.6V 2.0 IN EN High-Level Input Voltage V V IH V = 3.7V to 5.5V 2.4 IN EN Low-Level Input Voltage V V = 2.7V to 5.5V 0.8 V IL IN EN Input Current V = V or GND -1 1 A EN IN V = 5V, C = 150F from EN driven low IN OUT Startup Time 1ms to 50% full V OUT CURRENT LIMIT Overload Output Current I Force V to 4.5V 1.4 1.75 2.1 A LIMIT OUT Short-Circuit Output Current I OUT shorted to GND 1 1.4 A SC SUPPLY CURRENT Supply Current, Low-Level Input V = V = V = 5.5V 0.002 1 A EN IN OUT Timer not running 16 25 Supply Current, High-Level I V = 0, I = 0 A Q EN OUT Input Timer running 35 T = +25C 0.01 2 V = V = 5.5V, A EN IN Supply-Leakage Current A V = 0 OUT T = 0C to +85C 15 A UNDERVOLTAGE LOCKOUT Undervoltage Lockout UVLO Rising edge, 100mV hysteresis 2.0 2.4 2.6 V OVERCURRENT (OC) OC Threshold 1.1 A OC Output Low Voltage V I = 1mA, V = 3V 0.4 V OL SINK IN 2 MAX1922