Datasheet LTC1773 (Analog Devices) - 3

LTC1773
ELECTRICAL CHARACTERISTICS Note 1:
Stresses beyond those listed under Absolute Maximum Ratings
Note 3:
TJ is calculated from the ambient temperature TA and power dissipation may cause permanent damage to the device. Exposure to any Absolute PD according to the following formula: Maximum Rating condition for extended periods may affect device LTC1773: TJ = TA + (PD • 120°C/W) reliability and lifetime.
Note 4
: The LTC1773 is tested in a feedback loop which servos VFB to the
Note 2:
The LTC1773 is guaranteed to meet performance specifications from balance point for the error amplifier (VITH = 0.8V) 0°C to 70°C. Specifications over the –40°C to 85°C operating temperature
Note 5:
Dynamic supply current is higher due to the gate charge being range are assured by design, characterization and correlation with statistical delivered at the switching frequency. process controls.
Note 6:
Rise and fall times are measured using 10% and 90% levels.
W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Load Current Efficiency vs Load Current Efficiency vs Input Voltage
100 VIN = 5V V V OUT = 2.5V OUT = 2.5V 100 V 100 OUT = 2.5V SEE FIGURE 1 SEE FIGURE 1 SEE FIGURE 1 VIN = 3.3V 95 90 90 IOUT = 1A VIN = 5V 90 80 80 Burst Mode VIN = 8V OPERATION 85 EFFICIENCY (%) 70 EFFICIENCY (%) 70 EFFICIENCY (%) SYNC(750kHz) IOUT = 100mA 80 60 60 FORCED CONTINUOUS 50 50 75 1 10 100 1000 5000 1 10 100 1000 10,000 2 4 6 8 10 OUTPUT CURRENT (mA) INPUT VOLTAGE (V) OUTPUT CURRENT (mA) 1773 G01 1773 G02 1773 G03
VIN-VOUT Dropout Voltage Input and Shutdown Currents Load Regulation vs Load Current vs Input Voltage
0 400 500 R R SENSE = 0.025Ω SENSE = 0.025Ω 450 SEE FIGURE 1 350 VOUT = 1.8V – 0.05 Si9801DY 400 SYNC TO 750kHz 300 (%) µA) 350 VOUT = 1.8V – 0.10 250 Si9801DY OUT 300 R (mV) SENSE = 0.025Ω – 0.15 200 250 L = CDRH6D28-3RO OUT-V 200 INV 150 Burst Mode OPERATION – 0.20 INPUT CURRENT ( 150 NORMALIZED V 100 100 – 0.25 50 50 SHUTDOWN – 0.30 0 0 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0 500 1000 1500 2000 2500 2 4 6 8 10 LOAD CURRENT (A) LOAD CURRENT (mA) INPUT VOLTAGE (V) 1773 G16 1773 G05 1773 G06 1773fb 3