Datasheet LTC3621, LTC3621-2 (Analog Devices) - 4

LTC3621/LTC3621-2
elecTrical characTerisTics The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TJ = 25°C. (Note 3) VIN = 12V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VMODE/SYNC Pulse-Skipping Mode 0.3 V Burst Mode Operation VINTVCC – 0.4 V Forced Continuous Mode 1.0 VINTVCC – 1.2 V IMODE/SYNC MODE/SYNC Input Current 0 20 nA tSS Internal Soft-Start Time 0.8 ms ILIM Peak Current Limit 1.44 1.60 1.76 A (E/I-Grade) l 1.30 1.80 A (H-Grade) l 1.2 1.80 A VUVLO VINTVCC Undervoltage Lockout VIN Ramping Up 2.4 2.6 2.7 V VUVLO(HYS) VINTVCC Undervoltage Lockout Hysteresis 250 mV VOVLO VIN Overvoltage Lockout Rising l 18 19 20 V VOVLO(HYS) VIN Overvoltage Lockout Hysteresis 300 mV fOSC Oscillator Frequency LTC3621/LTC3621-3.3/LTC3621-5 0.92 1.00 1.08 MHz (E/I-Grade) l 0.82 1.16 MHz (H-Grade) l 0.78 1.16 MHz LTC3621-2/LTC3621-23.3/LTC3621-25 2.05 2.25 2.45 MHz (E/I-Grade) l 1.8 2.6 MHz (H-Grade) l 1.7 2.6 MHz fSYNC SYNC Capture Range 60 140 % VINTVCC VINTVCC LDO Output Voltage VIN > 4V 3.6 V ΔVPGOOD Power Good Range ±7.5 ±12.5 % RPGOOD Power Good Resistance PGOOD RDS(ON) at 500µA 275 350 Ω tPGOOD PGOOD Delay PGOOD Low to High 0 Cycles PGOOD High to Low 32 Cycles IPGOOD PGOOD Leakage Current 100 nA
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 4:
The quiescent current in forced continuous mode does not include may cause permanent damage to the device. Exposure to any Absolute switching loss of the power FETs. Maximum Rating condition for extended periods may affect device
Note 5:
The LTC3621 is tested in a proprietary test mode that connects VFB reliability and lifetime. to the output of error amplifier.
Note 2:
Transient absolute maximum voltages should not be applied for
Note 6:
TJ is calculated from the ambient, TA, and power dissipation, PD, more than 4% of the switching duty cycle. according to the following formula:
Note 3:
The LTC3621 is tested under pulsed load conditions such that TJ = TA + (PD • θJA) TJ ≈ TA. The LTC3621E is guaranteed to meet specifications from
Note 7:
This IC includes overtemperature protection that is intended 0°C to 85°C junction temperature. Specifications over the –40°C to to protect the device during momentary overload conditions. Junction 125°C operating junction temperature range are assured by design, temperature will exceed 150°C when overtemperature protection is active. characterization and correlation with statistical process controls. The Continuous operation above the specified maximum operating junction LTC3621I is guaranteed over the –40°C to 125°C operating junction temperature may impair device reliability. temperature range, and the LTC3621H is guaranteed over the –40°C to 150°C operating junction temperature range. High junction temperatures degrade operating lifetimes; operating lifetime is derated for junction temperatures greater than 125°C. Note that the maximum ambient temperature consistent with these specifications is determined by specific operating conditions in conjunction with board layout, the rated package thermal impedance and other environmental factors. 3621fc 4 For more information www.linear.com/LTC3621 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts