LT4220 Dual Supply Hot Swap Controller FEATURES DESCRIPTIO TM n Hot Swap Controller for Positive The LT 4220 16-pin dual voltage Hot Swap controller and Negative Supplies allows a board to be safely inserted and removed from a n Supply Tracking Mode live backplane. The device operates with any combination n 2.7V to 16.5V Operation of 2.7V to 16.5V and 2.7V to 16.5V supplies. Using two n Analog Current Limit with Foldback external N-channel pass transistors, the board supply n Allows Safe Board Insertion and Removal voltages can be ramped up at an adjustable rate. A select- from a Live Backplane able tracking mode allows dual supply tracking control for n Open-Collector Power Good Comparators ramping the positive and negative supplies together. n Automatic Retry or Latchoff After a Current Fault The LT4220 features foldback current limit and latches off n Dual Undervoltage Lockout Comparator Inputs both gates if either supply remains in current limit longer n Current Fault Indication than an adjustable time period. The IC can be configured U for automatic restart after a delay set by the same timer. APPLICATIO S A power good signal indicates when the output voltages n Live Board Insertion monitored by the two FB comparators are within tolerance, n RAID Systems and the gate drive signals are at their full on voltage. n 5.2V ECL Supplies The LT4220 is available in a 16-lead narrow SSOP n Industrial Controls package. n Split Supply Systems , LTC and LT are registered trademarks of Linear Technology Corporation. Hot Swap is a trademark of Linear Technology Corporation. TYPICAL APPLICATIO 12V 10A Hot Swap Controller + R Q1 S + 0.005 SUB85N03-04 V 12V IN 12V + V CC V OUT R13 10 C1 + Z1* R5 R6 10nF C4 CL1 10 1k 100nF 716 15 14 + + R1 R15 12V TRACK V SENSE GATE CC D1 R9 10 36.5k 20k V + IN PWRGD IN4001 12 36.5k + ON R16, 20k 13 + FB 11 R2 FAULT R10 12V 4.99k C7 8 TIMER 4.99k V + OUT 10nF C6 LT4220 1F 9 R12 GND 4.99k 12V 5 R4 C8 V FB IN 4.99k 10nF 6 R11 ON 36.5k D2 V 12V EE SENSEK SENSE GATE R3 IN4001 C2 V OUT 36.5k 12 34 R8 10nF C5 1k TIME (10ms/DIV) 1F C3 + R7 100nF CL2 10 Z2* R14 R S 10 0.005 V IN 12V 12V V V Q2 OUT EE * 1SMA13AT3 TRANSIENT SUB85N03-04 4220 TA01 VOLTAGE SUPPRESSOR 4220f 1 CONNECTOR 2 CONNECTOR 1 U ULT4220 ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION (Notes 1, 2) V to GND ............................................................. 22V CC TOP VIEW ORDER PART V to GND ........................................................... 22V EE NUMBER V 1 16 V EE CC TRACK, TIMER .............................. 0.3V to V + 0.3V + CC SENSEK 2 15 SENSE + + LT4220CGN + ON , FB ................................. V 0.3V to V + 0.3V EE CC SENSE 3 14 GATE LT4220IGN + ON , FB .................................. V 0.3V to V + 0.3V GATE 4 13 FB EE CC + + GATE ................................................ 0.3V to V + 8V FB 5 12 ON CC ON 6 11 FAULT GATE .............................. 16.5V with V = 22V to 0V EE GN PART MARKING + TRACK 7 10 PWRGD SENSE ............................................. 0.3V to V + 5V CC TIMER 8 9 GND SENSE , SENSEK ....................... V 0.3V to V + 3V EE EE 4220 PWRGD, FAULT ................................. 0.3V to V + 5V GN PACKAGE CC 4220I 16-LEAD PLASTIC SSOP Operating Temperature Range T = 125 C, q = 130 C/W JMAX JA LT4220C ........................................... 0 C T 70 C A Consult LTC Marketing for parts specified with wider operating temperature ranges. LT4220I ....................................... 40 C T 85 C A Storage Temperature Range ................. 65 C to 150 C Lead Temperature (Soldering, 10 sec).................. 300 C DC ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25 C. V = 5V, V = 5V, unless otherwise noted. A CC EE SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS V V Operating Range l 2.7 16.5 V CC CC I V Supply Current l 2.7 4 mA CC CC V V Operating Range l 2.7 16.5 V EE EE I V Supply Current 1.6 2.4 mA EE EE V V Undervoltage Lockout l 2.35 2.45 2.55 V PLKO CC V V Undervoltage Lockout l 2.4 2.45 2.5 V MLKO EE + + V + ON ON Threshold ON Rising l 1.22 1.24 1.26 V ON H + + V ON Hysteresis l 25 50 70 mV ON HYS + D V + ON ON Threshold Line Regulation V = 2.7V, V = 2.7V to V = 16.5V, V = 16.5V l 0.02 0.15 mV/V ON H CC EE CC EE D V ON ON Threshold Line Regulation V = 2.7V, V = 2.7V to V = 16.5V, V = 16.5V l 0.05 1 mV/V ON H CC EE CC EE V ON Hysteresis l 25 50 70 mV ON HYS V ON ON Voltage Threshold ON Falling l 1.22 1.24 1.26 V ON H + + I + ON Input Current V = 2V l 0.01 1 m A ON ON I ON Input Current V = GND l 0.01 1 m A ON ON + + V + FB PWRGD Voltage Threshold FB Rising l 1.22 1.24 1.26 V FB H + V + FB Hysteresis Gate = 5V l 25 50 70 mV FB HYS V FB PWRGD Voltage Threshold FB Falling l 1.22 1.24 1.26 V FB H V FB Hysteresis Gate = 3V l 25 50 70 mV FB HYS 4220f 2 U W U U WWW