Datasheet LT3752, LT3752-1 (Analog Devices) - 7

LT3752/LT3752-1
ELECTRICAL CHARACTERISTICS The
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denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, UVLO_VSEC = 2.5V. PARAMETER CONDITIONS MIN TYP MAX UNITS
OUT High Level INTVCC = 12V 11.9 V OUT Low Level in Shutdown UVLO_VSEC = 0V, INTVCC = 8V, IOUT = 1mA Into 0.25 V the Pin OUT (Volt-Sec) Max Duty Cycle Clamp RT = 24.9k, RIVSEC = 51.1k, FB = 1V, SS1 = 2.7V DVSEC (1 • System Input (Min)) × 100 UVLO_VSEC = 1.25V 68.5 72.5 76.2 % DVSEC (2 • System Input (Min)) × 100 UVLO_VSEC = 2.50V 34.3 36.5 38.7 % DVSEC (4 • System Input (Min)) × 100 UVLO_VSEC = 5.00V 17.5 18.6 19.7 % OUT Minimum ON Time COUT = 3.3nF, INTVCC = 12V (Note 9) RTBLNK = 14.7k 325 ns RTBLNK = 73.2k (Note 16) 454 ns
SS1 Pin (Soft-Start: Frequency and DVSEC) (Soft-Stop: COMP Pin, Frequency and DVSEC)
SS1 Reset Threshold (VSS1(RTH)) 150 mV SS1 Active Threshold (VSS1(ACT)) (Allow Switching) 1.25 V SS1 Charge Current (Soft-Start) SS1 = 1.5V (Note 10) 7 11.5 16 µA SS1 Discharge Current (Soft-Stop) SS1 = 1V, UVLO_VSEC = VSYS_UV – 50mV 6.4 10.5 14.6 µA SS1 Discharge Current (Hard Stop) SS1 = 1V OC > OC Threshold 0.9 mA INTVCC < INTVCC UVLO(–) 0.9 mA OVLO > OVLO(+) 0.9 mA
SS2 Pin (Soft-Start: Comp Pin)
SS2 Discharge Current SS1 < VSS(ACT), SS2 = 2.5V 2.8 mA SS2 Charge Current SS1 > VSS(ACT), SS2 = 1.5V 11 21 28 µA
Error Amplifier (Housekeeping Controller)
HFB Reference Voltage 0.90 1.000 1.10 V HFB Line Reg 6.5V < VIN < 100V (LT3752) 0.1 mV/V 10.5V < VIN < 16V (LT3752-1) 0.1 mV/V HFB Load Reg HCOMP VSW – 0.1V < HCOMP < HCOMP VOH – –6 mV/V 0.1V HFB Input Bias Current HFB = 1.1V (Note 10) 85 170 nA Transconductance ∆IHCOMP ±5µA 250 µS Voltage Gain 175 V/V Power Good(+) (HFB Level) 0.96 V Power Good(–) (HFB Level) 0.92 V HFB OVLO(+) (Disable HOUT Switching) 1.206 V HFB OVLO(–) (Enable Housekeeping Operation) 1.150 V HCOMP Source Current HCOMP = 1.75V (Note 10) 11 15 19 µA HCOMP Sink Current HCOMP = 1.75V 13 18 23 µA HCOMP Output High Clamp 2.9 V HCOMP Switching Threshold 1.28 V
Current Sense (Housekeeping Controller)
HISENSE Peak Current Threshold HFB = 0.8V 69 79 86.5 mV HCOMP Current Mode Gain ∆VHCOMP/∆VHISENSE 9.1 V/V HISENSE Input Current (D = 0%) (Note 10) 2 µA HISENSE Input Current (D = 80%) 52 µA HISENSE Overcurrent Threshold 84.6 98 105.4 mV Rev. C For more information www.analog.com 7 Document Outline Features Applications Typical Application Description Table of Contents Absolute Maximum Ratings Order Information Pin Configuration Order Information Electrical Characteristics Pin Functions Block Diagram Timing Diagrams Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts