Datasheet LTC1778, LTC1778-1 (Analog Devices) - 4

LTC1778/LTC1778-1
W U TYPICAL PERFOR A CE CHARACTERISTICS Transient Response Transient Response (Discontinuous Mode) Start-Up
RUN/SS VOUT VOUT 2V/DIV 50mV/DIV 50mV/DIV VOUT 1V/DIV IL IL 5A/DIV 5A/DIV IL 5A/DIV 20µs/DIV 1778 G01 20µs/DIV 1778 G02 50ms/DIV 1778 G19 LOAD STEP 0A TO 10A LOAD STEP 1A TO 10A VIN = 15V VIN = 15V VIN = 15V VOUT = 2.5V VOUT = 2.5V VOUT = 2.5V RLOAD = 0.25Ω FCB = 0V FCB = INTVCC FIGURE 9 CIRCUIT FIGURE 9 CIRCUIT
Efficiency vs Load Current Efficiency vs Input Voltage Frequency vs Input Voltage
100 100 300 FCB = 5V FCB = 0V FIGURE 9 CIRCUIT FIGURE 9 CIRCUIT DISCONTINUOUS 90 280 MODE 95 IOUT = 10A ILOAD = 1A 80 260 CONTINUOUS 90 MODE ILOAD = 10A 70 240 IOUT = 0A EFFICIENCY (%) EFFICIENCY (%) FREQUENCY (kHz) 85 V 60 IN = 10V 220 VOUT = 2.5V EXTVCC = 5V FIGURE 9 CIRCUIT 50 80 200 0.001 0.01 0.1 1 10 0 5 10 15 20 25 30 5 10 15 20 25 LOAD CURRENT (A) INPUT VOLTAGE (V) INPUT VOLTAGE (V) 1778 G03 1778 G04 1778 G05
Frequency vs Load Current Load Regulation ITH Voltage vs Load Current
300 0 2.5 FIGURE 9 CIRCUIT FIGURE 9 CIRCUIT CONTINUOUS MODE 250 2.0 –0.1 200 DISCONTINUOUS 1.5 MODE (%) 150 –0.2 CONTINUOUS OUTV MODE ∆ VOLTAGE (V) 1.0 100 I TH FREQUENCY (kHz) –0.3 DISCONTINUOUS 0.5 50 MODE 0 –0.4 0 0 2 4 6 8 10 0 2 4 6 8 10 0 5 10 15 LOAD CURRENT (A) LOAD CURRENT (A) LOAD CURRENT (A) 1778 G26 1778 G06 1778 G07 1778fb 4