LTC3608 e lectrical characteristics The l denotes the specifications which apply over the full operating junction temperature range, otherwise specifications are at TA = 25°C. VIN = 15V unless otherwise noted.SYMBOLPARAMETERCONDITIONSMINTYPMAXUNITSInternal VCC Regulator VINTVCC Internal VCC Voltage 6V < VIN < 18V, VEXTVCC = 4V l 4.7 5 5.5 V ΔVLDO(LOADREG) Internal VCC Load Regulation ICC = 0mA to 20mA, VEXTVCC = 4V –0.1 ±2 % VEXTVCC EXTVCC Switchover Voltage ICC = 20mA, VEXTVCC Rising l 4.5 4.7 V ΔVEXTVCC EXTVCC Switch Drop Voltage ICC = 20mA, VEXTVCC = 5V 150 300 mV ΔVEXTVCC(HYS) EXTVCC Switchover Hysteresis 500 mV PGOOD Output ΔVFBH PGOOD Upper Threshold VFB Rising 7 10 13 % ΔVFBL PGOOD Lower Threshold VFB Falling –7 –10 –13 % ΔVFB(HYS) PGOOD Hysteresis VFB Returning 1 2.5 % VPGL PGOOD Low Voltage IPGOOD = 5mA 0.15 0.4 V Note 1: Stresses beyond those listed under Absolute Maximum Ratings Note 4: The LTC3608 is tested under pulsed load conditions such that may cause permanent damage to the device. Exposure to any Absolute TJ ≈ TA. The LTC3608E is guaranteed to meet specifications from Maximum Rating condition for extended periods may affect device 0°C to 125°C junction temperature. Specifications over the –40°C to reliability and lifetime. 125°C operating junction temperature range are assured by design, Note 2: T characterization and correlation with statistical process controls. The J is calculated from the ambient temperature TA and power dissipation P LTC3608I is guaranteed over the full –40°C to 125°C operating junction D as follows: T temperature range. Note that the maximum ambient temperature J = TA + (PD • 29°C/W)(θJA is simulated per JESD51-7 high effective thermal conductivity test board) consistent with these specifications is determined by specific operating θ conditions in conjunction with board layout, the rated package thermal JC = 1°C/W (θJC is simulated when heat sink is applied at the bottom of the package.) impedance and other environmental factors. Note 3: The LTC3608 is tested in a feedback loop that adjusts VFB to achieve a specified error amplifier output voltage (ITH). The specification at 85°C is not tested in production. This specification is assured by design, characterization, and correlation to testing at 125°C. typical perForMance characteristics Transient ResponseTransient ResponseStart-Up VOUT VOUT 200mV/DIV 200mV/DIV RUN/SS 2V/DIV I IL L 5A/DIV 5A/DIV VOUT 1V/DIV I I LOAD LOAD IL 5A/DIV 5A/DIV 5A/DIV 3608 G03 3608 G01 20µs/DIV 3610 G02 40ms/DIV 20µs/DIV LOAD STEP 0A TO 8A V V IN = 12V IN = 12V V V IN = 12V V OUT = 2.5V OUT = 2.5V V R OUT = 2.5V FCB = INTV LOAD = 0.5Ω CC FCB = 0V FIGURE 6 CIRCUIT FIGURE 6 CIRCUIT FIGURE 6 CIRCUIT 3608fc Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts