LTC4244/LTC4244-1 Rugged, CompactPCI Bus Hot Swap Controllers FEATURES DESCRIPTIO TM n Controls 12V, 3.3V, 5V and 12V Supplies The LTC 4244/LTC4244-1 are Hot Swap controllers that n 14.4V Absolute Maximum Rating for 12V allow a board to be safely inserted into and removed from IN TM and 12V Input Pins a CompactPCI bus slot. External N-channel transistors IN n Insensitive to Supply Voltage Transients control the 5V and 3.3V supplies while on-chip switches n Adjustable Foldback Current Limit with Circuit Breaker control the 12V supplies. The 3.3V and 5V supplies can n LOCAL PCI RST Logic On-Chip be ramped up at an adjustable rate. Electronic circuit n PRECHARGE Output Biases I/O Pins During Card breakers protect all four supplies against overcurrent Insertion and Extraction faults. After the power-up cycle is complete, the TIMER pin n LTC4244-1 Designed for Applications without 12V capacitor serves as auxiliary V allowing the LTC4244/ CC n Available in 20-Lead Narrow SSOP Package LTC4244-1 to function without interruption in the pres- ence of voltage spikes on the 12V supply. The PWRGD IN U output indicates when all four supplies are within toler- APPLICATIO S ance. The OFF/ON pin is used to cycle board power or reset n Hot Board Insertion into CompactPCI Bus the circuit breaker. The PRECHARGE output can be used to bias the bus I/O pins during card insertion and extrac- , LTC and LT are registered trademarks of Linear Technology Corporation. tion. PCI RST is combined on-chip with HEALTHY in Hot Swap is a trademark of Linear Technology Corporation. CompactPCI is a trademark of the PCI Industrial Computer Manufacturers Group. order to generate LOCAL PCI RST . TYPICAL APPLICATIO C8 C9 0.01F PER 0.01F PER R2 Q2 5V IN POWER PIN POWER PIN 0.007 IRF7457 V OUT 5V 5V + R22 5A C 2.7 R1 Q1 LOAD(5VOUT) LONG 5V 0.005 IRF7457 V 3.3V OUT IN 3.3V 3.3V + R21 7A C 1.8 Z3 LOAD(3.3VOUT) LONG 3.3V R3 R4 C1 Z4 C6 C7 10 10 R5 0.33F 0.01F 0.01F 1k Z1 Z2 3.3V 3.3V GATE 3.3V 5V 5V 5V IN SENSE OUT IN SENSE OUT V OUT 12V 12V 12V IN OUT 12V + 500mA V 12V EEIN C LOAD(12VOUT) R19 1k OFF/ON V BD SEL EEOUT V R20 12V EEOUT R18 10k LTC4244 C 100mA 1.2k LOAD(VEEOUT) LONG V(I/O) FAULT R17 10k TIMER PWRGD C2 HEALTHY 0.082F R6 PCI RST RESETIN 10k V OUT GND PRECHARGE RESETOUT DRIVE 3.3V R15 R16 LOCAL PCI RST 1 1 R9 24 C3 4.7nF R8 1k C4 C5 0.01F 0.01F V IN GROUND 3.3V Q3 R10 18 R7 12 R11 R12 R13 1V MMBT2222A RESET 10k 10k 10 I/O DATA LINE 1 10% I/O 1 I/O PIN 1 PCI R14 BRIDGE 10 I/O DATA LINE 128 I/O 128 CHIP I/O PIN 128 Z1, Z2: SMAJ12A Z3, Z4: SMAJ5.0A 4244 F01 Figure 1. Typical Compact PCI Application 42441f 1 + U ULTC4244/LTC4244-1 UUW ABSOLUTE AXI U RATI GS PACKAGE/ORDER I FOR ATIO (Notes 1, 2, 3) Supply Voltages ORDER PART TOP VIEW NUMBER 12V ................................................................ 14.4V IN 12V 1 20 12V IN OUT V .............................................................. 14.4V EEIN V 2 19 V EEIN EEOUT LTC4244CGN Input Voltages (OFF/ON, RESETIN) ........0.3V to 13.5V 5V 3 18 3.3V OUT OUT LTC4244CGN-1 Output Voltages (FAULT, PWRGD, RESETOUT) TIMER 4 17 3.3V IN LTC4244IGN ...........................................................0.3V to 13.5V OFF/ON 5 16 3.3V SENSE LTC4244IGN-1 FAULT 6 15 GATE Analog Voltages and Currents PWRGD 7 14 5V 5V , DRIVE, 5V , 3.3V , 3.3V , 3.3V , 5V SENSE OUT IN SENSE IN OUT SENSE GND 8 13 5V IN ...........................................................0.3V to 13.5V RESETIN 9 12 PRECHARGE PRECHARGE, GATE ....................................... 20mA RESETOUT 10 11 DRIVE V ................................................ 14.4V to 0.3V EEOUT GN PACKAGE TIMER, 12V ...........................................0.3V to 14.4V OUT 20-LEAD PLASTIC SSOP Operation Temperature Range T = 140C, = 135C/ W JMAX JA LTC4244C/LTC4244C-1........................... 0C to 70C LTC4244I/LTC4244I-1 ........................ 40C to 85C Consult LTC Marketing for parts specified with wider operating temperature ranges. Storage Temperature Range ................. 65C to 150C Lead Temperature (Soldering, 10 sec).................. 300C ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at T = 25C. V = 12V, V = 12V, V = 3.3V, V = 5V, unless A 12VIN EEIN 3.3VIN 5VIN otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS I V Supply Current OFF/ON = 0V l 410 mA DD 12VIN V Undervoltage Lockout 12V , Ramping Down l 8 9 10 V LKO IN 5V , Ramping Down l 4 4.25 4.5 V IN 3.3V , Ramping Down l 2.25 2.5 2.75 V IN , Ramping Up (LTC4244 Only) l 8.25 9.25 10.25 V V EEIN TIMER, Ramping Down, V = 6V l 8.25 9.25 10.25 V 12VIN V Foldback Current Limit Voltage V = (V V ), V = 0V, TIMER = 0V l 11 16 21 mV FB FB 5VIN 5VSENSE 5VOUT V = (V V ), V = 3V, TIMER = 0V l 46 51 56 mV FB 5VIN 5VSENSE 5VOUT V = (V V ), V = 0V, TIMER = 0V l 11 16 21 mV FB 3.3VIN 3.3VSENSE 3.3VOUT V = (V V ), V = 2V, TIMER = 0V l 46 51 56 mV FB 3.3VIN 3.3VSENSE 3.3VOUT V Circuit Breaker Trip Voltage V = (V V ), TIMER = FLOAT l 45 52 57 mV CB CB 5VIN 5VSENSE V = (V V ), TIMER = FLOAT l 45 52 57 mV CB 3.3VIN 3.3VSENSE t Overcurrent Fault Response Time (V V ) = 100mV, TIMER = FLOAT l 17 25 35 s OC 5VIN 5VSENSE (V V ) = 100mV, TIMER = FLOAT l 17 25 35 s 3.3VIN 3.3VSENSE I GATE Pin Output Current OFF/ON = 0V, V = 2V, TIMER = 0V l 20 67 100 A GATE(UP) GATE I V = 5V, OFF/ON = 4V l 20 60 100 A GATE(DN) GATE I OFF/ON = 0V, V = 2V, TIMER = FLOAT, FAULT = 0V l 4 8 16 mA GATE(FAULT) GATE V External Gate Voltage V = (V V ), I = 1A l 0.6 1 V GATE GATE 12VIN GATE GATE V Internal Switch Voltage Drop V = (V V ), I = 500mA l 225 600 mV 12V 12V 12VIN 12VOUT V V = (V V ), I = 100mA l 110 250 mV VEE VEE EEOUT EEIN EE 42441f 2 U WWW