Datasheet LTC3803-3 (Analog Devices) - 3

LTC3803-3
ELECTRICAL CHARACTERISTICS The
l
denotes the specifi cations which apply over the full operating junction temperature range, otherwise specifi cations are at TA = 25°C. VCC = 8V, unless otherwise noted. (Notes 2, 3) SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
VCLAMP25mA VCC Shunt Regulator Voltage ICC = 25mA, VITH/RUN = 0V LTC3803E-3, LTC3803I-3 l 8.4 9.5 10.5 V LTC3803H-3 l 8.4 9.5 10.7 V LTC3803MP-3 l 8.1 9.5 10.7 V VMARGIN VCLAMP1mA – VTURNON Margin LTC3803E-3, LTC3803I-3, LTC3803H-3 l 0.05 0.6 V LTC3803MP-3 l 0.03 0.6 V ICC Input DC Supply Current (Note 4) Normal Operation VITH/RUN = 1.3V 240 350 μA Start-Up VCC = VTURNON – 100mV 40 90 μA VITHSHDN Shutdown Threshold (at ITH/RUN) VCC > VTURNON, VITH/RUN Falling LTC3803E-3 l 0.15 0.28 0.45 V LTC3803I-3, LTC3803H-3 l 0.10 0.28 0.45 V LTC3803MP-3 l 0.09 0.28 0.45 V IITHSTART Start-Up Current Source VITH/RUN = 0V 0.2 0.3 0.4 μA VFB Regulated Feedback Voltage (Note 5) 0°C ≤ TJ ≤ 85°C 0.788 0.800 0.812 V LTC3803E-3: –40°C ≤ TJ ≤ 85°C l 0.780 0.800 0.812 V LTC3803I-3: –40°C ≤ TJ ≤ 125°C l 0.780 0.800 0.820 V LTC3803H-3: –40°C ≤ TJ ≤ 150°C l 0.780 0.800 0.820 V LTC3803MP-3: –55°C ≤ TJ ≤ 150°C l 0.780 0.800 0.820 V VIMAX Peak Current Sense Voltage RSL = 0 (Note 6) LTC3803E-3 l 90 100 115 mV LTC3803I-3, LTC3803H-3 l 85 100 115 mV LTC3803MP-3 l 85 100 120 mV gm Error Amplifi er Transconductance ITH/RUN Pin Load = ±5μA (Note 5) 200 333 500 μA/V ΔVO(LINE) Output Voltage Line Regulation (Note 5) 0.05 mV/V IFB VFB Input Current (Note 5) 10 50 nA fOSC Oscillator Frequency VITH/RUN = 1.3V 270 300 330 kHz DCON(MIN) Minimum Switch On Duty Cycle VITH/RUN = 1.3V, VFB = 0.8V 8 9.6 % DCON(MAX) Maximum Switch On Duty Cycle VITH/RUN = 1.3V, VFB = 0.8V 70 80 90 % tRISE Gate Drive Rise Time CLOAD = 3000pF 40 ns tFALL Gate Drive Fall Time CLOAD = 3000pF (Note 7) 40 ns ISLMAX Peak Slope Compensation Output Current (Note 7) 5 μA tSFST Soft-Start Time 1.4 ms
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings conjunction with board layout, the rated package thermal impedance and may cause permanent damage to the device. Exposure to any Absolute other environmental factors. Maximum Rating condition for extended periods may affect device
Note 3:
Junction temperature TJ is calculated from the ambient reliability and lifetime. temperature TA and power dissipation PD according to the following
Note 2:
The LTC3803-3 is tested under pulsed load conditions such formula: that TJ ≈ TA. The LTC3803E-3 is guaranteed to meet specifi cations TJ = TA + (PD • 230°C/W). from 0°C to 85°C junction temperature. Specifi cations over the –40°C
Note 4:
Dynamic supply current is higher due to the gate charge being to 125°C operating junction temperature range are assured by design, delivered at the switching frequency. characterization and correlation with statistical process controls. The
Note 5:
The LTC3803-3 is tested in a feedback loop that servos V LTC3803I-3 is guaranteed over the –40°C to 125°C operating junction FB to the output of the error amplifi er while maintaining I temperature range, the LTC3803H-3 is guaranteed over the –40°C to TH/RUN at the midpoint of the current limit range. 150°C operating junction temperature range and the LTC3803MP-3 is tested and guaranteed over the full –55°C to 150°C operating junction
Note 6:
Peak current sense voltage is reduced dependent on duty cycle temperature range. High junction temperatures degrade operating and an optional external resistor in series with the SENSE pin (RSL). For lifetimes; operating lifetime is derated for junction temperatures greater details, refer to the programmable slope compensation feature in the than 125°C. Note that the maximum ambient temperature consistent with Applications Information section. these specifi cations is determined by specifi c operating conditions in
Note 7:
Guaranteed by design. 38033fd 3 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS BLOCK DIAGRAM OPERATION APPLICATIONS INFORMATION TYPICAL APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS