Datasheet LTC1735 (Analog Devices) - 4

LTC1735
ELECTRICAL CHARACTERISTICS Note 3:
The LTC1735 is tested in a feedback loop that servos VOSENSE to
Note 6:
The minimum on-time condition corresponds to an inductor peak- the balance point for the error amplifier (VITH = 1.2V). to-peak ripple current ≥40% of IMAX (see Minimum On-Time
Note 4:
Dynamic supply current is higher due to the gate charge being Considerations in the Applications Information section). delivered at the switching frequency. See Applications Information.
Note 7:
Rise and fall times are measured using 10% and 90% levels. Delay
Note 5:
Oscillator frequency is tested by measuring the C times are measured using 50% levels. OSC charge current (I
Note 8:
The LTC1735E is guaranteed to meet performance specifications OSC) and applying the formula: from 0°C to 85°C. Specifications over the –40°C to 85°C operating  1 – 8.477 1011 ( )   1 1  temperature range are assured by design, characterization and correlation fOSC = with statistical process controls. The LTC1735I specifications are  C p ( F) +  + 11  I I OSC CHG DIS   guaranteed over the full –40°C to 85°C operating temperature range.
W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Load Current (3 Operating Modes) Efficiency vs Load Current Efficiency vs Input Voltage
100 100 100 EXTVCC OPEN EXTVCC = 5V EXTVCC = 5V V 90 FIGURE 1 IN = 15V VOUT = 1.6V 90 95 FIGURE 1 BURST VIN = 5V 80 SYNC 80 90 70 V IOUT = 5A CONTINUOUS IN = 24V 60 70 85 IOUT = 0.5A EFFICIENCY (%) 50 EFFICIENCY (%) 60 EFFICIENCY (%) 80 40 VIN = 10V VOUT = 3.3V 50 75 30 RS = 0.01Ω fO = 300kHz 20 40 70 0.001 0.01 0.1 1 10 0.01 0.1 1 10 0 5 10 15 20 25 30 LOAD CURRENT (A) LOAD CURRENT (A) INPUT VOLTAGE (V) 1735 G01 1735 G02 1735 G03
VIN – VOUT Dropout Voltage Efficiency vs Input Voltage Load Regulation vs Load Current
100 0 500 EXTV R CC OPEN FCB = 0V SENSE = 0.005Ω V V OUT = 1.6V VIN = 15V OUT = 5V – 5% DROP 95 FIGURE 1 FIGURE 1 400 –0.1 90 (%) IOUT = 5A OUT (mV) 300 85 –0.2 OUT I – V OUT = 0.5A 200 IN EFFICIENCY (%) 80 V NORMALIZED V –0.3 100 75 70 –0.4 0 0 5 10 15 20 25 30 0 2 4 6 8 10 0 2 4 6 8 10 INPUT VOLTAGE (V) LOAD CURRENT (A) LOAD CURRENT (A) 1735 G04 1735 G05 1735 G06 1735fc 4