Datasheet LTC3727, LTC3727-1 (Analog Devices) - 6

LTC3727/LTC3727-1
W U TYPICAL PERFOR A CE CHARACTERISTICS Dropout Voltage vs Output Current SENSE Pins Total Source Current (Figure 13) RUN/SS Current vs Temperature
100 1.4 1.8 VOUT = 5V 50 1.6 1.2 0 1.4 –50 1.0 μA) 1.2 RSENSE = 0.015Ω μA) –100 0.8 ( 1.0 –150 0.6 0.8 I SENSE –200 0.6 –250 0.4 DROPOUT VOLTAGE (V) RUN/SS CURRENT ( 0.4 –300 0.2 –350 R 0.2 SENSE = 0.010Ω –400 0 0 0 5 10 15 0 1 2 3 4 5 –50 –25 0 25 50 75 100 125 VSENSE COMMON MODE VOLTAGE (V) OUTPUT CURRENT (A) TEMPERATURE (°C) 3727 G13 3727 G14 3727 G15
Soft-Start Up (Figure 12) Load Step (Figure 12) Load Step (Figure 12)
IOUT* 5A/DIV VOUT V 200mV/DIV OUT 200mV/DIV VOUT 5V/DIV V IOUT* IOUT* RUN/SS 5V/DIV 2A/DIV 2A/DIV VIN = 20V 50ms/DIV 3727 G16 VIN = 15V 50μs/DIV 3727 G17 VIN = 15V 50μs/DIV 3727 G18 VOUT = 12V VOUT = 12V VOUT = 12V LOAD STEP = 0A TO 3A LOAD STEP = 0A TO 3A Burst Mode OPERATION CONTINUOUS MODE
Input Source/Capacitor Constant Frequency (Burst Inhibit) Instantaneous Current (Figure 12) Burst Mode Operation (Figure 12) Operation (Figure 12)
IIN VOUT VOUT 1A/DIV 20mV/DIV 20mV/DIV VSW1 20V/DIV V I SW2 I OUT* OUT* 20V/DIV 0.5A/DIV 0.5A/DIV VIN = 15V 1μs/DIV 3727 G19 VIN = 15V 50μs/DIV 3727 G20 VIN = 15V 5μs/DIV 3727 G21 VOUT1 = 12V VOUT = 12V VOUT = 12V VOUT2 = 5V VFCB = OPEN VFCB = 7.5V IOUT1 = IOUT2 = 2A IOUT = 20mA IOUT = 20mA *IOUT ⇒ INDUCTOR CURRENT 3727fc 6