MAX4943MAX4946/MAX4944L/MAX4945A/MAX4945L/MAX4949 19-0552 Rev 3 6/08 Overvoltage-Protection Controllers with Internal FET General Description Features The MAX4943MAX4946/MAX4949 family of overvolt- Input Voltage Protection Up to +28V age-protection devices feature a low 80m (typ) R ON Integrated nFET Switch internal FET and protect low-voltage systems against Preset Overvoltage Protection Trip Level voltage faults up to +28V. These devices also drive an 7.40V (MAX4943) optional external pFET to protect down to -28V when 6.35V (MAX4944 ) connected to a load with reverse current protection. When the input voltage exceeds the overvoltage thresh- 5.80V (MAX4945 ) old, the internal FET is turned off to prevent damage to 4.56V (MAX4946) the protected components. 8.90V (MAX4949) All switches feature a minimum 1.2A current-limit pro- Low-Current Undervoltage-Lockout Mode tection. During a short-circuit occurrence, the Short-Circuit Protection (Latchoff/Autoretry) MAX4944B and MAX4945B place the switch in a Internal 15ms (typ) Startup Delay and Retry Times latchoff state where the switch turns off and remains off. For the autoretry devices, the switch turns off and con- Input Voltage Power-Good Logic Output tinuously checks after a 15ms (typ) retry time. Thermal-Shutdown Protection The overvoltage thresholds (OVLO) are preset to 7.4V, Small, 8-Pin (2mm x 2mm) DFN Package 6.35V, 5.8V, 4.56V, or 8.9V. The undervoltage-lockout (UVLO) thresholds are preset to 2.45V and 4.15V. When the input voltage drops below the undervoltage- Pin Configuration lockout (UVLO) threshold, the devices enter a low- current standby mode. (See the Ordering Information/ TOP VIEW Selector Guide for more details on UVLO/OVLO). + All devices are offered in a small, 8-pin DFN (2mm x 1 8 OUT IN MAX4943 2mm) package and are specified for operation over the MAX4946/ IN 2 7 OUT MAX4944L/ -40C to +85C temperature range. GP 3 6 OUT MAX4945A/ MAX4945L/ Applications ACOK 4 5 GND MAX4949 Cell Phones PDAs and Palmtop Devices DFN 2mm 2mm Digital Still Cameras MP3 Players Ordering Information/Selector Guide PART PIN-PACKAGE TOP MARK PKG CODE UVLO (V) OVLO (V) OVERCURRENT MODE MAX4943ELA+T* 8 DFN ABA L822-1 4.15 7.40 Retry MAX4944ELA+T 8 DFN ABB L822-1 4.15 6.35 Retry MAX4944BELA+T* 8 DFN ABC L822-1 4.15 6.35 Latchoff MAX4944LELA+T 8 DFN ABD L822-1 2.45 6.35 Retry MAX4945ELA+T** 8 DFN ABE L822-1 4.15 5.80 Retry MAX4945AELA+T** 8 DFN ADW L822-1 4.15 5.80 Retry MAX4945BELA+T* 8 DFN ABF L822-1 4.15 5.80 Latchoff MAX4945LELA+T 8 DFN ABG L822-1 2.45 5.80 Retry MAX4946ELA+T 8 DFN ABH L822-1 2.45 4.56 Retry MAX4949ELA+T 8 DFN ADT L822-1 2.45 8.90 Latchoff Note: All devices are specified over the -40C to +85C operating temperature range. +Denotes a lead-free/RoHS-compliant package. T = Tape-and-reel package. *Future productcontact factory for availability. **The OVLO is 6.10V (max) for the MAX4945ELA+T and .6.0V (max) for the MAX4945AELA+T. 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.Overvoltage-Protection Controllers with Internal FET ABSOLUTE MAXIMUM RATINGS IN............................................................................-0.3V to +30V Operating Temperature Range ...........................-40C to +85C OUT ...............................................................-0.3V to (IN + 0.3V) Junction Temperature......................................................+150C GP...........................................................................-0.3V to +12V Storage Temperature Range .............................-65C to +150C IN to GP..................................................................-0.3V to +22V Lead Temperature (soldering, 10s) .................................+300C ACOK .......................................................................-0.3V to +6V Continuous Power Dissipation (T = +70C) A 8-Pin DFN (derate 4.8mW/C above +70C) ..............381mW 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 (MAX4943/MAX4944 /MAX4945 /MAX4949), V = +3V (MAX4946), T = -40C to +85C, unless otherwise noted. IN IN A Typical values are at T = +25C.) (Note 1) A PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Voltage Range V 2.2 28.0 V IN V = 3V (MAX4946) 50 150 IN Input Supply Current I A IN V = 5V, all remaining parts 50 150 IN UVLO Supply Current I V = 2.2V 30 A UVLO IN MAX4943/MAX4944/ MAX4944B/MAX4945/ 3.90 4.15 4.40 MAX4945A/ MAX4945B IN Undervoltage Lockout V (V falling) V UVLO IN MAX4944L/MAX4945L/ 2.30 2.45 2.60 MAX4946/MAX4949 IN Undervoltage-Lockout 1% Hysteresis MAX4943 7.00 7.4 7.80 MAX4944 6.00 6.35 6.70 MAX4945/MAX4945B/L 5.50 5.80 6.10 Overvoltage Trip Level V (V rising) V OVLO IN MAX4945A 5.50 5.80 6.00 MAX4946 4.30 4.56 4.82 MAX4949 8.20 8.90 9.60 IN Overvoltage Hysteresis 1% V = 3V (MAX4946), I = 1A 80 200 IN OUT Switch On-Resistance R m ON V = 5V, all remaining parts, I = 1A 80 200 IN OUT T = +25C 1.2 1.7 4.0 A MAX4943MAX4946 T = T to T 1.2 1.7 4.0 A MIN MAX Overcurrent Protection Threshold I A LIM T = +25C 2.0 3.5 5.0 A MAX4949 T = T to T 2.0 3.0 5.0 A MIN MAX GP Clamp Voltage I (V - V ), V = 28V 13 16 19 V GPD IN GP IN GP Pulldown Resistor R 50 k GPD 2 MAX4943MAX4946/MAX4944L/MAX4945A/MAX4945L/MAX4949