Datasheet LTC1871-7 (Analog Devices) - 3

LTC1871-7
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 = 8V, VRUN = 1.5V, RFREQ = 80k, VMODE/SYNC = 0V, unless otherwise specified. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V + RUN Rising RUN Input Threshold Voltage 1.348 V V – RUN Falling RUN Input Threshold Voltage 1.223 1.248 1.273 V ● 1.198 1.298 V VRUN(HYST) RUN Pin Input Threshold Hysteresis 50 100 150 mV I-Grade (Note 2) ● 35 100 175 mV IRUN RUN Input Current 5 60 nA VFB Feedback Voltage VITH = 0.2V (Note 5) 1.218 1.230 1.242 V ● 1.212 1.248 V VITH = 0.2V (Note 5), I-Grade (Note 2) ● 1.205 1.255 V IFB FB Pin Input Current VITH = 0.2V (Note 5) 18 60 nA ∆VFB Line Regulation 6V ≤ VIN ≤ 30V 0.002 0.02 %/V ∆VIN 6V ≤ VIN ≤ 30V, I-Grade (Note 2) ● 0.002 0.02 %/V ∆VFB Load Regulation VMODE/SYNC = 0V, VITH = 0.5V to 0.9V (Note 5) ● –1 –0.1 % ∆VITH VMODE/SYNC = 0V, VITH = 0.5V to 0.9V (Note 5) ● –1 –0.1 % I-Grade (Note 2) ∆VFB(OV) ∆FB Pin, Overvoltage Lockout VFB(OV) – VFB(NOM) in Percent 2.5 6 10 % gm Error Amplifier Transconductance ITH Pin Load = ±5µA (Note 5) 600 µmho VITH(BURST) Burst Mode Operation ITH Pin Voltage Falling ITH Voltage (Note 5) 0.3 V VSENSE(MAX) Maximum Current Sense Input Threshold Duty Cycle < 20% 120 150 180 mV Duty Cycle < 20%, I-Grade (Note 2) ● 100 200 mV ISENSE(ON) SENSE Pin Current (GATE High) VSENSE = 0V 35 70 µA ISENSE(OFF) SENSE Pin Current (GATE Low) VSENSE = 30V 0.1 5 µA
Oscillator
fOSC Oscillator Frequency RFREQ = 80k 250 300 350 kHz RFREQ = 80k, I-Grade (Note 2) ● 250 300 350 kHz Oscillator Frequency Range 50 1000 kHz I-Grade (Note 2) ● 50 1000 kHz DMAX Maximum Duty Cycle 87 92 97 % I-Grade (Note 2) ● 87 92 98.5 % fSYNC/fOSC Recommended Maximum Synchronized fOSC = 300kHz (Note 6) 1.25 1.30 Frequency Ratio fOSC = 300kHz (Note 6), I-Grade (Note 2) ● 1.25 1.30 tSYNC(MIN) MODE/SYNC Minimum Input Pulse Width VSYNC = 0V to 5V 25 ns tSYNC(MAX) MODE/SYNC Maximum Input Pulse Width VSYNC = 0V to 5V 0.8/fOSC ns VIL(MODE) Low Level MODE/SYNC Input Voltage 0.3 V I-Grade (Note 2) ● 0.3 V VIH(MODE) High Level MODE/SYNC Input Voltage 1.2 V I-Grade (Note 2) ● 1.2 V RMODE/SYNC MODE/SYNC Input Pull-Down Resistance 50 kΩ VFREQ Nominal FREQ Pin Voltage 0.62 V
Low Dropout Regulator
VINTVCC INTVCC Regulator Output Voltage VIN = 8V 6.5 7 7.5 V VIN = 8V, I-Grade (Note 2) ● 6.5 7 7.5 V 18717fd 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