Datasheet LTC3639 (Analog Devices) - 3

LTC3639
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the specified operating junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VIN = 12V, unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Output Supply (VFB)
VFB(ADJ) Feedback Comparator Threshold VFB Rising, VPRG1 = VPRG2 = 0V (Adjustable Output) LTC3639E, LTC3639I l 0.792 0.800 0.808 V LTC3639H, LTC3639MP l 0.788 0.800 0.812 V VFBH Feedback Comparator Hysteresis VFB Falling, VPRG1 = VPRG2 = 0V l 3 5 9 mV (Adjustable Output) IFB Feedback Pin Current VFB = 1V, VPRG1 = VPRG2 = 0V –10 0 10 nA VFB(FIXED) Feedback Comparator Thresholds VFB Rising, VPRG1 = SS, VPRG2 = 0V l 4.94 5.015 5.09 V (Fixed Output) VFB Falling, VPRG1 = SS, VPRG2 = 0V l 4.91 4.985 5.06 V VFB Rising, VPRG1 = 0V, VPRG2 = SS l 3.26 3.31 3.36 V VFB Falling, VPRG1 = 0V, VPRG2 = SS l 3.24 3.29 3.34 V VFB Rising, VPRG1 = VPRG2 = SS l 1.78 1.81 1.84 V VFB Falling, VPRG1 = VPRG2 = SS l 1.77 1.80 1.83 V
Operation
IPEAK Peak Current Comparator Threshold ISET Floating l 200 230 260 mA 100k Resistor from ISET to GND l 100 120 140 mA ISET Shorted to GND l 17 25 30 mA RON Power Switch On-Resistance Top Switch ISW = –50mA 4.2 Ω Bottom Switch ISW = 50mA 2.2 Ω ILSW Switch Pin Leakage Current VIN = 150V, SW = 0V 0.1 1 μA ISS Soft-Start Pin Pull-Up Current VSS < 2.5V 4 5 6 μA tINT(SS) Internal Soft-Start Time SS Pin Floating 1 ms
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings maximum ambient temperature consistent with these specifications is may cause permanent damage to the device. Exposure to any Absolute determined by specific operating conditions in conjunction with board Maximum Rating condition for extended periods may affect device layout, the rated package thermal impedance and other environmental reliability and lifetime. factors.
Note 2:
The LTC3639 is tested under pulsed load conditions such that
Note 3:
The junction temperature (TJ, in °C) is calculated from the ambient TJ ≈ TA. The LTC3639E is guaranteed to meet performance specifications temperature (TA, in °C) and power dissipation (PD, in Watts) according to from 0°C to 85°C. Specifications over the –40°C to 125°C operating the formula: junction temperature range are assured by design, characterization and TJ = TA + (PD • θJA) correlation with statistical process controls. The LTC3639I is guaranteed where θ over the –40°C to 125°C operating junction temperature range, the JA is 40°C/W for the MSOP package. LTC3639H is guaranteed over the –40°C to 150°C operating junction Note that the maximum ambient temperature consistent with these temperature range and the LTC3639MP is tested and guaranteed over the specifications is determined by specific operating conditions in –55°C to 150°C operating junction temperature range. conjunction with board layout, the rated package thermal impedance and other environmental factors. High junction temperatures degrade operating lifetimes; operating lifetime is derated for junction temperatures greater than 125°C. Note that the
Note 4:
Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. See Applications Information. 3639fc For more information www.linear.com/LTC3639 3 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 Typical Applications Package Description Revision History Typical Application Related Parts