Datasheet LTC3126 (Analog Devices) - 4

LTC3126
e lecTrical characTerisTics The
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denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). PVIN1, = VIN1 = 24V, PVIN2 = VIN2 = 12V, VSET1 = VSET2 = GND, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS
VIN1, VIN2 Input Valid Threshold, Falling VSET1 = VSET2 = 1000mV 17.57 17.75 17.93 V VSET1 = VSET2 = 500mV 8.77 8.86 8.95 V VSET1 = VSET2 = 250mV 4.34 4.43 4.52 V VSET1 = VSET2 = 150mV 2.57 2.65 2.73 V VIN1, VIN2 Input Valid Threshold Hysteresis As a Percentage of the Rising Threshold 11 % VIN1, VIN2 Input Valid Comparator Delay VIN1/VIN2 Falling, 2V/µs, VSET1/VSET2 = 1V 60 µs VIN1/VIN2 Rising, 2V/µs, VSET1/VSET2 = 1V 120 µs Open-Drain Output Voltage PGOOD, PRIORITY, VALID1, VALID2 5.5 V Open-Drain Pull-Down Resistance PGOOD, PRIORITY, VALID1, VALID2 70 Ω Open-Drain Leakage PGOOD, PRIORITY, VALID1, VALID2 1 µA Low Side Switch Resistance 70 mΩ High Side Switch Resistance 200 mΩ Dropout Voltage 1A Load, VOUT = 3.3V 310 mV High Side Switch Current Limit (Note 3) 3.0 3.9 4.8 A Low Side Switch Current Limit (Note 3) 3.8 5.2 6.8 A Zero Cross Threshold PWM/SYNC = Low (Note 3) 220 mA PWM/SYNC = High or Clocked (Note 3) 0 mA SW Leakage Current VIN1 = VIN2 = PVIN1 = PVIN2 = 42V, VSW = 0V, 42V –3 3 µA VCC Voltage IVCC = 1mA 4.12 4.22 4.32 V VCC Current Limit VCC = 3.5V 35 67 mA VCC Drop-Out Voltage Powered from VIN1 or VIN2, VIN = 2.4V, ILOAD = 5mA 70 mV Powered from EXTVCC, VEXTVCC = 3.3V, ILOAD = 5mA 100 mV VCC Load Regulation ILOAD = 1mA to 15mA 1.1 % EXTVCC Applied Voltage 3.15 42 V EXTVCC Valid, Rising Threshold l 2.95 3.05 3.15 V EXTVCC Valid, Hysteresis 167 mV EXTVCC Current in Shutdown EXTVCC = 3.3V, ENA = Low 0.2 µA EXTVCC Current Switching, fSW = 1MHz 8.8 mA Frequency Foldback Threshold on FB 200 mV SW Minimum On-Time VIN = 24V, 1A Load, EXTVCC = OPEN 46 ns SW Minimum Low-Time 100 ns SW Frequency Foldback Factor VFB < 0.2V 16 SW Frequency Divider in Drop-Out 8
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings 150°C operating junction temperature range. High temperatures degrade may cause permanent damage to the device. Exposure to any Absolute operating lifetimes; operating lifetime is derated for junction temperatures Maximum Rating condition for extended periods may affect device greater than 125°C. reliability and lifetime.
Note 3:
Current measurements are performed when the LTC3126 is
Note 2:
The LTC3126 is tested under pulsed load conditions such that not switching. The current limit values measured in operation will be TJ ≈ TA. The LTC3126E is guaranteed to meet specifications from somewhat higher due to the propagation delay of the comparators. 0°C to 85°C junction temperature. Specification over the –40°C to
Note 4:
This IC includes overtemperature protection that is intended to 125°C operating junction temperature range are assured by design, protect the device during momentary overload conditions. The maximum characterization and correlation with statistical process controls. The rated junction temperature will be exceeded when this protection is active. LTC3126I specifications are guaranteed over the –40°C to 125°C operating Continuous operation above the specified absolute maximum operating junction temperature range. The LTC3126H specifications are guaranteed junction temperature may impair device reliability or permanently damage over the –40°C to 150°C operating junction temperature range. The the device. LTC3126MP specifications are guaranteed and tested over the –55°C to 3126f 4 For more information www.linear.com/LTC3126 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Quick Reference Operation Applications Information Typical Applications Package Description Typical Application Related Parts