LT4256 LINER [Linear Technology], LT4256 Datasheet
LT4256
Available stocks
Related parts for LT4256
LT4256 Summary of contents
Page 1
FEATURES n Wide Operating Voltage Range: 2.5V to 34V n Overvoltage Protection to 60V n Reverse Supply Protection to –40V n Blocks 50Hz and 60Hz AC Power n No Input Capacitor or TVS Required for Most Applications n Adjustable Undervoltage ...
Page 2
LTC4365 ABSOLUTE MAXIMUM RATINGS Supply Voltage (Note 1) V .......................................................... –40V to 60V IN Input Voltages (Note 3) UV, SHDN .............................................. –0.3V to 60V OV ............................................................ –0. ....................................................... –0.3V to 40V OUT Output Voltages (Note 4) FAULT ...
Page 3
ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER OUT V Input Voltage Range IN I Input Supply Current VIN I Reverse Input Supply Current VIN(R) V Input Supply Undervoltage Lockout IN(UVLO ...
Page 4
LTC4365 TYPICAL PERFORMANCE CHARACTERISTICS V Operating Current vs IN Temperature 100 SHDN = 2. OUT 34V 12V 2. –50 – ...
Page 5
TYPICAL PERFORMANCE CHARACTERISTICS UV Threshold vs Temperature 507 12V IN OUT 505.0 502.5 500.0 497.5 495.0 492.5 –50 – 100 TEMPERATURE (°C) 4365 G10 UV/OV Propagation Delay vs Overdrive ...
Page 6
LTC4365 PIN FUNCTIONS Exposed Pad: Connect to device ground. FAULT: Fault Indication Output. This high voltage open drain output is pulled low below its monitor threshold above its monitor threshold, if SHDN is low, ...
Page 7
BLOCK DIAGRAM V IN –40V TO 60V LDO 6.5V INTERNAL V OUT 2.2V UVLO UV – + 25mV OV HYSTERESIS + – 0.5V REVERSE PROTECTION – + CLOSES SWITCH 5V INTERNAL WHEN V IS NEGATIVE SUPPLY IN SUPPLY GATE I ...
Page 8
LTC4365 OPERATION Many of today’s electronic systems get their power from external sources such as a wall wart adapter, batteries and custom power supplies. These power sources are often unreliable, wired incorrectly, out of spec, or just plain wrong. This ...
Page 9
APPLICATIONS INFORMATION Figure 2 highlights the dependence of the gate drive on V and V . When system power is first turned on (SHDN OUT low to high 0V), gate drive maximum for all OUT ...
Page 10
LTC4365 APPLICATIONS INFORMATION Figure 4 shows the timing associated with the UV pin. Once a UV fault propagates through the UV comparator ), the FAULT output is asserted low and a 50mA (t FAULT current sink discharges the GATE pin. ...
Page 11
APPLICATIONS INFORMATION The resistor values can then be solved: 3mV 1. R1 300k 10nA 3mV • • (3.5V – 0.5V) =1.8M 10nA The closest 1% value 1.82M: 300k +1.82M 3. R1 ...
Page 12
LTC4365 APPLICATIONS INFORMATION The trace the other hand, does not respond OUT to the negative voltage demonstrating the desired IN reverse supply protection. The waveforms of Figure 7 were captured using a 40V ...
Page 13
APPLICATIONS INFORMATION Select Between Two Input Supplies With the part in shutdown, the V IN driven by separate power supplies. The LTC4365 then automatically drives the GATE pin just below the lower of the two supplies, thus turning off the ...
Page 14
LTC4365 APPLICATIONS INFORMATION Transients During OV Fault The circuit of Figure 14 was used to display transients during an overvoltage condition. The nominal input supply is 24V and it has an overvoltage threshold of 30V. The parasitic inductance is that ...
Page 15
PACKAGE DESCRIPTION 0.52 MAX 3.85 MAX 2.62 REF RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.20 BSC DATUM ‘A’ 0.30 – 0.50 REF NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING ...
Page 16
... LTC3835/LTC3835-1 Low I , Synchronous Step-Down Controller Q LT3845 Low I , Synchronous Step-Down Controller Q LT3850 Dual, 550kHz, 2-Phase Synchronous Step-Down Controller LT4256 Positive 48V Hot Swap Controller with Open-Circuit Detect LTC4260 Positive High Voltage Hot Swap Controller with 2 ADC and I C LTC4352 Ideal MOSFET ORing Diode ...