MAX4838A/MAX4840A/MAX4842A 19-3979 Rev 0 2/06 Overvoltage-Protection Controllers with Status FLAG General Description Features The MAX4838A/MAX4840A/MAX4842A are overvoltage- Overvoltage Protection Up to +28V protection ICs that protect low-voltage systems against Preset 7.4V, 5.8V, or 4.7V Overvoltage Trip Level voltages of up to +28V. If the input voltage exceeds the Drives Low-Cost nMOS FET overvoltage trip level, the MAX4838A/MAX4840A/ MAX4842A turn off the low-cost external n-channel Internal 50ms Startup Delay FET(s) to prevent damage to the protected components. Internal Charge Pump An internal charge pump eliminates the need for external capacitors and drives the FET gate for a simple, Undervoltage Lockout robust solution. 15kV ESD-Protected Input The MAX4838A has a 7.4V overvoltage threshold, and Voltage Fault FLAG Indicator the MAX4840A has a 5.8V overvoltage threshold. The 6-Pin SC70 and DFN Packages MAX4842A has a 4.7V overvoltage threshold. The MAX4838A/MAX4840A have an undervoltage-lockout Lead Free (UVLO) threshold of 3.25V, while the MAX4842A has a UVLO of 2.5V. In addition to the single FET configura- tion, the devices can be configured with back-to-back Ordering Information external FETs to prevent currents from being back-dri- ven into the adapter. PIN- TOP PKG PART PACKAGE MARK CODE On power-up, the device waits for 50ms before driving GATE high. FLAG is held low for an additional 50ms MAX4838AEXT+T 6 SC70 ACY X6S-1 after GATE goes high before deasserting. The MAX4838AELT+ 6 DFN KU L611-1 MAX4838A/MAX4840A/MAX4842A have an open-drain MAX4840AEXT+T 6 SC70 ACZ X6S-1 FLAG output. The FLAG output asserts immediately to an overvoltage fault. MAX4840AELT+ 6 DFN KV L611-1 MAX4842AEXT+T 6 SC70 ADA X6S-1 Additional features include a 15kV (HBM) ESD-pro- tected input (when bypassed with a 1F capacitor) and MAX4842AELT+* 6 DFN KW L611-1 a shutdown pin (EN) to turn off the device. Note: All devices specified for the -40C to +85C extended All devices are offered in a small 6-pin SC70 and 6-pin temperature range. 1.5mm x 1.0mm DFN packages and are specified *Future productcontact factory for availability. over the -40C to +85C extended temperature range. +Denotes lead-free package. Applications Cell Phones Typical Operating Circuit Digital Still Cameras INPUT PDAs and Palmtop Devices OUTPUT +1.2V TO +28V MP3 Players NMOS 1 4 IN GATE 1F V IO Selector Guide MAX4838A MAX4840A OV UVLO MAX4842A TRIP EN FLAG 6 PART THRESHOLD 3 EN LEVEL INPUT OUTPUT FLAG (V) NOTE: EN AND PULLUP (V) 2 GND RESISTOR MAX4838A 3.25 7.4 Yes Open-Drain MAX4840A 3.25 5.8 Yes Open-Drain Pin Configuration appears at end of data sheet. MAX4842A 2.50 4.7 Yes Open-Drain Maxim Integrated Products 1 For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct at 1-888-629-4642, or visit Maxims website at www.maxim-ic.com.Overvoltage-Protection Controllers with Status FLAG ABSOLUTE MAXIMUM RATINGS IN to GND ..............................................................-0.3V to +30V Operating Temperature Range ..........................-40C to +85C GATE to GND ........................................................-0.3V to +12V Junction Temperature .................................................... +150C EN, FLAG to GND ....................................................-0.3V to +6V Storage Temperature Range ............................-65C to +150C Continuous Power Dissipation (T = +70C) Lead Temperature (soldering, 10s) ................................+300C A 6-Pin SC70 (derate 3.1mW/C above +70C) .............245mW 6-Pin DFN (derate 2.1mW/C above +70C) ............477mW 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 (MAX4838A/MAX4840A), V = +4V (MAX4842A), T = -40C to +85C, unless otherwise noted. Typical values are at T IN IN A A = +25C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Input Voltage Range V 1.2 28.0 V IN MAX4838A/MAX4840A 3.0 3.25 3.5 Undervoltage-Lockout Threshold UVLO V falling V IN MAX4842A 2.3 2.5 2.7 Undervoltage-Lockout Hysteresis 50 mV V rising MAX4838A 7.0 7.4 7.8 IN Overvoltage Trip Level OVLO V V rising MAX4840A 5.5 5.8 6.1 IN V rising MAX4842A 4.4 4.7 5.0 IN MAX4838A 100 Overvoltage Trip Level Hysteresis MAX4840A 80 mV MAX4842A 50 No load, EN = GND or 5V, 80 200 V = 5V (MAX4838A/MAX4840A) IN IN Supply Current I A IN No load, EN = GND or 4.0V, 75 160 V = 4V (MAX4842A) IN V = 2.9V (MAX4838A/MAX4840A) 30 IN UVLO Supply Current I A UVLO V = 2.2V (MAX4842A) 22 IN MAX4838A/MAX4840A910 GATE Voltage V I sourcing 1A V GATE GATE MAX4842A 7.5 8.0 GATE Pulldown Current I V > V , V = 5.5V 27 mA PD IN OVLO GATE 1.2V V < UVLO, IN 0.4 I = 50A SINK FLAG Output Low Voltage V FLAG asserted V OL V OVLO, I = IN SINK 0.4 1mA FLAG Output High Leakage I V = 5.5V, FLAG deasserted 1 A OH FLAG EN Input High Voltage V 1.5 V IH EN Input Low Voltage V 0.4 V IL EN Input Leakage I EN = GND or 5.5V 1 A LKG 2 MAX4838A/MAX4840A/MAX4842A