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LTC4234 – 20A Guaranteed SOA Hot Swap Controller

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LTC4234 – 20A Guaranteed SOA Hot Swap Controller LTC4234 20A Guaranteed SOA Hot Swap Controller FEATURES DESCRIPTION n Allows Safe Board Insertion into Live Backplane The LTC ®4234 is an integrated solution for Hot Swap™ n Small Footprint applications that allows a board to be safely inserted and n 4mΩ MOSFET Including RSENSE removed from a live backplane. The part integrates a n Safe Operating Area Guaranteed at 81W, 30ms Hot Swap controller, power MOSFET and current sense n Wide Operating Voltage Range: 2.9V to 15V resistor in a single package for small form factor applica- n Adjustable, 11% Accurate Current Limit tions. The MOSFET Safe Operating Area is production tested n Current and Temperature Monitor Outputs and guaranteed for the stresses in Hot Swap applications. n Overtemperature Protection The LTC4234 provides separate inrush current control n Adjustable Current Limit Timer Before Fault and an 11% accurate 22.5A current limit with output n Power Good and Fault Outputs dependent foldback. The current limit threshold can be n Adjustable Inrush Current Control adjusted dynamically using the ISET pin. Additional features n 2.5% Accurate Undervoltage and Overvoltage Protection include a current monitor output that amplifies the sense n Pin Compatible with LTC4233 resistor voltage for ground referenced current sensing n Available in a 38-Pin (5mm × 9mm) QFN Package and a MOSFET temperature monitor output. Thermal limit, overvoltage, undervoltage and power good monitoring are APPLICATIONS also provided. For a 10A compatible version, see LTC4233. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and n High Availability Servers Hot Swap and PowerPath are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. n Solid State Drives n Industrial n 240W, 12V Systems TYPICAL APPLICATION 12V, 20A Card Resident Application with Auto-Retry VOUT Power-Up Waveform 12V VDD OUT 12V + 20A * 150k 1000µF 107k UV FB VIN CONTACT 10V/DIV FLT 20k 10k BOUNCE 5.23k LTC4234 IIN 0.2A/DIV OV PG 10k – SENSE GATE VOUT SENSE 10V/DIV TIMER I SET PG INTVCC IMON ADC 10V/DIV 1µF GND 20k 4234 TA01a 20ms/DIV 4234 TA01b *TVS: DIODES INC. SMAJ17A 4234fa For more information www.linear.com/LTC4234 1 LTC4234 ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION (Notes 1, 2) TOP VIEW Supply Voltage (VDD) ................................. –0.3V to 28V Input Voltages UV 1 38 ISET FB, OV, UV ..............................................–0.3V to 12V OV 2 37 FB 39 I 3 36 FLT TIMER ................................................... –0.3V to 3.5V MON V − DD SENSE , SENSE .....VDD − 10V or –0.3V to VDD + 0.3V TIMER 4 35 PG – Output Voltages INTVCC 5 34 SENSE VDD (DNC) 6 33 VDD (DNC) ISET, IMON ................................................. –0.3V to 3V GND 7 32 GATE PG, FLT ................................................. –0.3V to 35V SENSE (DNC) 8 31 SENSE OUT ............................................ –0.3V to VDD + 0.3V OUT 9 30 OUT INTVCC .................................................. –0.3V to 3.5V OUT 10 29 OUT 40 GATE (Note 3) ........................................ –0.3V to 33V OUT 11 28 OUT SENSE Operating Ambient Temperature Range OUT 12 27 OUT OUT 13 26 OUT LTC4234C ................................................ 0°C to 70°C OUT 14 25 OUT LTC4234I .............................................–40°C to 85°C OUT 15 24 OUT LTC4234H .......................................... –40°C to 125°C OUT 16 23 OUT Junction Temperature (Notes 4, 5) ........................ 150°C 17 18 19 20 21 22 Storage Temperature Range .................. –65°C to 150°C OUT OUT OUT OUT OUT OUT WHH PACKAGE 38-LEAD (5mm × 9mm) PLASTIC QFN TJMAX = 150°C, θJA = 15°C/W EXPOSED PADS (PINS 39 and 40) ARE VDD AND SENSE θJA = 15°C/W SOLDERED, OTHERWISE θJA = 50°C/W ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL PART MARKING PACKAGE DESCRIPTION TEMPERATURE RANGE LTC4234CWHH#PBF LTC4234CWHH#TRPBF 4234 38-Lead (5mm × 9mm) Plastic QFN 0°C to 70°C LTC4234IWHH#PBF LTC4234IWHH#TRPBF 4234 38-Lead (5mm × 9mm) Plastic QFN –40°C to 85°C LTC4234HWHH#PBF LTC4234HWHH#TRPBF 4234 38-Lead (5mm × 9mm) Plastic QFN –40°C to 125°C Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on nonstandard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ 4234fa 2 For more information www.linear.com/LTC4234 LTC4234 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VDD = 12V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS DC Characteristics l VDD Input Supply Range 2.9 15 V l IDD Input Supply Current MOSFET On, No Load 1.6 3 mA l VDD(UVL) Input Supply Undervoltage Lockout VDD Rising 2.63 2.73 2.85 V l IOUT OUT Leakage Current VOUT = VGATE = 0V, VDD = 15V 0 ±700 µA l VOUT = VGATE = 12V 1 2 4 µA l dVGATE/dt OUT Turn-On Ramp Rate GATE Open 0.15 0.35 0.6 V/ms l RON MOSFET + Sense Resistor On-Resistance C-Grade, I-Grade 2.3 4.0 7.2 mΩ l H-Grade 2.3 4.0 8.2 mΩ l ILIM(TH) Current Limit Threshold VFB = 1.35V, ISET Open 20 22.5 25 A l VFB = 0V, ISET Open 4 5.7 7.4 A l VFB = 1.35V, RSET = 20k 9.4 11.1 12.8 A SOA MOSFET Safe Operating Area 13.5V, 6A Folded Back, 200W2s (Note 6) 30 ms 7.5V, 22A Onset of Foldback, 200W2s (Note 7) 7 ms Inputs l IIN OV, UV, FB Input Current V = 1.2V 0 ±1 µA − − l ISENSE−(IN) SENSE Input Current VSENSE = 12V 4 ±10 µA l VTH OV, UV, FB Threshold Voltage VPIN Rising 1.205 1.235 1.265 V l ∆VOV(HYST) OV Hysteresis 10 20 30 mV l ∆VUV(HYST) UV Hysteresis 50 80 110 mV l VUV(RTH) UV Reset Threshold Voltage VUV Falling 0.55 0.62 0.7 V l ∆VFB(HYST) FB Power Good Hysteresis 10 20 30 mV l RISET ISET Internal Resistor 19 20 21 kΩ Outputs l VINTVCC INTVCC Output Voltage VDD = 5V,15V, ILOAD = 0mA, –10mA 2.8 3.1 3.3 V l VOL PG, FLT Output Low Voltage I = 2mA 0.4 0.8 V l IOH PG , FLT Input Leakage Current V = 30V 0 ±10 µA l VTIMER(H) TIMER High Threshold VTIMER Rising 1.2 1.235 1.28 V l VTIMER(L) TIMER Low Threshold VTIMER Falling 0.1 0.21 0.3 V l ITIMER(UP) TIMER Pull-Up Current VTIMER = 0V –80 –100 –120 µA l ITIMER(DN) TIMER Pull-Down Current VTIMER = 1.2V 1.4 2 2.6 µA l ITIMER(RATIO) TIMER Current Ratio ITIMER(DN)/ITIMER(UP) 1.6 2 2.7 % l AIMON IMON Current Gain 4.5 5 5.25 µA/A BWIMON IMON Bandwidth 250 kHz l IOFF(IMON) IMON Offset Current IOUT = 600mA 0 ±9 µA l IGATE(UP) Gate Pull-Up Current Gate Drive On, VGATE = VOUT = 12V –18 –24 –29 µA l IGATE(DN) Gate Pull-Down Current Gate Drive Off, VGATE = 18V, VOUT = 12V 180 250 500 µA IGATE(FST) Gate Fast Pull-Down Current Fast Turn Off, VGATE = 18V, VOUT = 12V 140 mA 4234fa For more information www.linear.com/LTC4234 3 LTC4234 ELECTRICAL CHARACTERISTICS The l denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VDD = 12V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS AC Characteristics l tPHL(GATE) Input High (OV), Input Low (UV) to GATE VGATE < 17.8V Falling 8 20 µs Low Propagation Delay − l tPHL(ILIM) Short Circuit to GATE Low VFB = 0, Step VDD − SENSE to 50mV, VGATE < 1 5 µs 15V Falling l tD(ON) Turn-On Delay Step VUV to 2V, VGATE > 13V 24 48 72 ms tD(FAULT) UV Low to Clear Fault Latch Delay 1 µs − l tD(CB) Circuit Breaker Filter Delay Time (Internal) VFB = 0, Step VDD − SENSE to 50mV 1.2 2 2.7 ms l tD(COOL_DOWN) Cool Down Delay (Internal) 600 900 1200 ms Note 1: Stresses beyond those listed under Absolute Maximum Ratings Continuous operation above the specified maximum operating junction may cause permanent damage to the device. Exposure to any Absolute temperature may impair device reliability. Maximum Rating condition for extended periods may affect device Note 5: TJ is calculated from the ambient temperature, TA, and power reliability and lifetime. dissipation, PD, according to the formula: Note 2: All currents into pins are positive; all voltages are referenced to TJ = TA + (PD • 15°C/W) GND unless otherwise specified. Note 6: SOA tested at room temperature. SOA (i.e. P2t), is reduced at Note 3: An internal clamp limits the GATE pin to a maximum of 6.5V elevated temperatures according to the following formula: above OUT. Driving this pin to voltages beyond the clamp may damage the 2 150°C– T device. P2t T = 200W2s • J ( J ) Note 4: This IC includes overtemperature protection that is intended 150°C–25°C to protect the device during momentary overload conditions. Junction Note 7: Guaranteed by design and extrapolated from P2t limit of 200W2s. temperature will exceed 150°C when overtemperature protection is active. 4234fa 4 For more information www.linear.com/LTC4234 LTC4234 TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C, VDD = 12V unless otherwise noted. UV Low-High Threshold IDD vs VDD INTVCC Load Regulation vs Temperature 2.2 3.5 1.240 VDD = 5V 3.0 125°C 1.236 25°C 2.5 1.8 VDD = 3.3V –40°C (V) 2.0 CC (mA) 1.232 DD I 1.5 INTV 1.4 1.0 1.228 UV LOW-HIGH THRESHOLD (V) 0.5 1.0 0 1.224 0 5 10 15 20 25 30 0 –2 –4 –6 –8 –10 –12 –14 –50 –25 0 25 50 75 100 125 150 VDD (V) ILOAD (mA) TEMPERATURE (°C) 4234 G02 4234 G01 4234 G03 Timer Pull-Up Current Current Limit Delay UV Hysteresis vs Temperature vs Temperature (tPHL(ILIM) vs Overdrive) 0.10 –110 1000 –105 100 0.08 –100 10 0.06 UV HYSTERESIS (V) –95 1 TIMER PULL-UP
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