Datasheet LT8228 (Analog Devices) - 6

LT8228
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. DS1 = V1D = 48V, DS2 = BIAS = 14V, RIN1 = 1k, RIN2 = 1k, and ISHARE = INTVCC unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
IB2 SNS2P, SNS2N Bias Current 2.5V < VCM2 < 100V l –105 –90 –70 µA VCM2 = 0V l 35 50 70 µA IISET2P ISET2P Output Current VRSNS2 = 1mV l 0.0 1.0 2.2 µA 2.5V < VCM2 < 100V VRSNS2 = 25mV l 24.0 25.0 26.0 µA VRSNS2 = 50mV l 48.5 50.0 51.5 µA VRSNS2 = 80mV l 78.0 80.0 82.0 µA IISET2N ISET2N Output Current VRSNS2 = –1mV l 0.0 1.0 2.2 µA 2.5V < VCM2 < 100V VRSNS2 = –25mV l 24.0 25.0 26.0 µA VRSNS2 = –50mV l 48.5 50.0 51.5 µA VRSNS2 = –80mV l 78.0 80.0 82.0 µA IIMON2 IMON2 Output Current VRSNS2 = –80mV l 78.0 80.0 82.0 µA 2.5V < VCM2 < 100V VRSNS2 = –50mV l 48.5 50.0 51.5 µA VRSNS2 = –25mV l 24.0 25.0 26.0 µA VRSNS2 = –1mV l 0.0 1.0 2.2 µA VRSNS2 = 1mV l 0.0 1.0 2.2 µA VRSNS2 = 25mV l 24.0 25.0 26.0 µA VRSNS2 = 50mV l 48.5 50.0 51.5 µA VRSNS2 = 80mV l 78.0 80.0 82.0 µA IISET2P, IISET2N, Output Current, VCM1 < 2.5V |VRSNS1| = 1mV l 0.0 1.0 3.0 µA IMON2, |VRSNS1| = 25mV l 22.5 25.0 27.5 µA |VRSNS1| = 50mV l 47.5 50.0 52.5 µA |VRSNS1| = 80mV l 76.0 80.0 84.0 µA IISHARE ISHARE Output Current, ISHARE = 0V VRSNS1 = –1mV l 0.0 1.0 2.2 µA DRXN = 0V (Boost Mode), VRSNS1 = –25mV l 24.0 25.0 26.0 µA 2.5V < VCM1 < 100V VRSNS1 = –50mV l 48.5 50.0 51.0 µA VRSNS1 = –80mV l 78.0 80.0 82.0 µA ISHARE Output Current, ISHARE = 0V VRSNS2 = 1mV l 0.0 1.0 2.2 µA DRXN = 2V (Buck Mode), VRSNS2 = 25mV l 24.0 25.0 26.0 µA 2.5V < VCM1 < 100V VRSNS2 = 50mV l 48.5 50.0 51.0 µA VRSNS2 = 80mV l 78.0 80.0 82.0 µA ISHARE Output Current, ISHARE = 0V VRSNS1 = –1mV l 0.0 1.0 3.0 µA DRXN = 0V (Boost Mode), VRSNS1 = –25mV l 22.5 25.0 27.5 µA VCM1 < 2.5V VRSNS1 = –50mV l 47.5 50.0 52.5 µA VRSNS1 = –80mV l 76.0 80.0 84.0 µA ISHARE Output Current, ISHARE = 0V VRSNS2 = 1mV l 0.0 1.0 3.0 µA DRXN = 2V (Buck Mode), VRSNS2 = 25mV l 22.5 25.0 27.5 µA VCM2 < 2.5V VRSNS2 = 50mV l 47.5 50.0 52.5 µA VRSNS2 = 80mV l 76.0 80.0 84.0 µA
Buck Voltage and Current Regulation
VFB2 FB2 Regulation Voltage (Note 13) l 1.198 1.210 1.222 V IFB2 FB2 Pin Bias Current l 10 50 nA gmFB1 V2 Error Amplifier Transconductance 0.8 ms VISET1P ISET1P Regulation Voltage (Note 14) l 1.198 1.210 1.222 V gmISET1P ISET1P Error Amplifier Transconductance 0.8 ms VISET2P ISET2P Regulation Voltage (Note 14) l 1.198 1.210 1.222 V gmISET2P ISET2P Error Amplifier Transconductance 0.8 ms RVC2 VC2 Output Impedance 1000 kΩ ∆ISET1P Buck Mode Input Current (ISET1P) Regulation RSNS1 = 5Ω, RSET1P = 24.3k, VCM1 = 48V, l 0 ±2.5 % Error (Note 15) DRXN = 2V (Buck Mode) Rev. 0 6 For more information www.analog.com Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Buck Efficiency and Operation Typical Performance Characteristics Boost Efficiency and Operation ENABLE, Supply Current and VCC SS Current, Frequency, Thresholds and Driver Protection MOSFET Controller Pin Functions Block Diagram Operation Overview Buck Mode Operation Boost Mode Operation V1 Protection MOSFET Controller Operation V2 Protection MOSFET Controller Operation Mode of Operation (DRXN) Enable and Soft-Start (Enable and SS) Paralleling Multiple Controllers (ISHARE AND IGND) BIAS Supply and VCC Regulators Strong Gate Drivers Frequency Selection, Spread Spectrum and Phase-Locked Loop (RT and SYNC) FAULT Monitoring and REPORT Feature Applications Information Introduction Programming the Switching Frequency Inductor Selection RSNS2 and RIN2 Selection for Peak Inductor Current RSET2P Selection for V2 Output Current Limit (Buck Mode) RSET2N Selection for V2 Input Current Limit (Boost Mode) RMON2 Selection for V2 Current Monitoring RSNS1 and RIN1 Selection RSET1P Selection for V1 Input Current Limit (Buck Mode) RSET1N Selection for V1 Output Current Limit (Boost Mode) RMON1 Selection for V1 Current Monitoring Output Voltage, Input Undervoltage and Output Overvoltage Programming Power MOSFET Selection and Efficiency Considerations Optional Schottky Diode (D2 and D3) Selection Top MOSFET Driver Supply (CBST, DBST) Power Path Capacitor Selection Loop Compensation Inrush Current Control Boost Output Short Protection and Timer FAULT Conditions Soft-Start REPORT Feature Paralleling Multiple LT8228s BIAS, DRVCC, INTVCC and Power Dissipation Thermal Shutdown Pin Clearance/Creepage Consideration Efficiency Considerations PC Board Layout Checklist Design Example Package Description Typical Application Related Parts Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Typical Application Related Parts