Datasheet LTC3544 (Analog Devices) - 4
| Manufacturer | Analog Devices |
| Description | Quad Synchronous Step-Down Regulator: 2.25MHz, 300mA, 200mA, 200mA, 100mA |
| Pages / Page | 16 / 4 — ELECTRICAL CHARACTERISTICS. Note 3:. Note 5:. Note 6:. Note 4:. Note 7:. … |
| File Format / Size | PDF / 300 Kb |
| Document Language | English |
ELECTRICAL CHARACTERISTICS. Note 3:. Note 5:. Note 6:. Note 4:. Note 7:. Note 8:. TYPICAL PERFORMANCE CHARACTERISTICS
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Text Version of Document
LTC3544
ELECTRICAL CHARACTERISTICS Note 3:
TJ is calculated from the ambient temperature TA and power
Note 5:
The LTC3544 is tested in a proprietary test mode that connects VFB dissipation PD according to the following formula: to the output of the error amplifi er. TJ = TA + (PD)(68°C/W).
Note 6:
Load regulation is inferred by measuring the regulation loop gain.
Note 4:
This IC includes overtemperature protection that is intended
Note 7:
The QFN switch on-resistance is guaranteed by correlation to wafer to protect the device during momentary overload conditions. Junction level measurements. temperature will exceed 125°C when overtemperature is active. Continuous
Note 8:
Guaranteed by long-term current density limitations. operation above the specifi ed maximum operating junction temperature may impair device reliability.
TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current 300mA VREF vs Temperature at 2.25V, Switching Frequency vs Supply Channel. All Other Channels at 3.6V, 5.5V Voltage and Temperature 50% Peak Current
0.815 3.0 100 CHANNEL 200A ILOAD CHANNEL 100 = 50mA I 90 LOAD = 100mA ALL CHANNELS OPERATING 0.810 ALL CHANNELS OPERATING 80 70 0805 2.5 60 (V) 0.800 50 REFV 40 VIN = 3.6V 0.795 2.0 EFFICIENCY (%) TA = 25°C 30 VOUT100 = 1.2V fOSC –40°C 20 VOUT200A = 0.8V 0.790 V SWITCHING FREQUENCY (MHz) f IN = 2.25V OSC 0°C VOUT200B = 1.5V V f IN = 3.6V OSC 25°C 10 VOUT300 = 1.8V V f IN = 5.5V OSC 80°C ALL OTHER CHANNELS LOADED 50% 0.785 1.5 0 –50 0 50 100 2 3 4 5 6 0.0001 0.001 0.01 0.1 1 TEMPERATURE (°C) SUPPLY VOLTAGE (V) LOAD CURRENT 300mA CHANNEL (A) 3544B G03 3544 G01 3544 G02
Burst Mode Operation Burst Mode Operation Burst Mode Operation 300mA Channel 200mA, A-B Channels 100mA Channel
VOUT300 VOUT200B VOUT100 50mV/DIV 50mV/DIV 50mV/DIV AC AC AC COUPLED COUPLED COUPLED SW300 SW2B SW100 5V/DIV 5V/DIV 5V/DIV I I I L L L 50mA/DIV 50mA/DIV 100mA/DIV 3544 G04 3544 G05 3544 G06 2μs/DIV 2μs/DIV 2μs/DIV VIN = 3.6V TA = 25°C VIN = 3.6V TA = 25°C VIN = 3.6V TA = 25°C VOUT = 1.8V ILOAD = 20mA VOUT = 1.5V ILOAD = 15mA VOUT = 1.2V ILOAD = 12mA 3544fa 4
ELECTRICAL CHARACTERISTICS Note 3:
TJ is calculated from the ambient temperature TA and power
Note 5:
The LTC3544 is tested in a proprietary test mode that connects VFB dissipation PD according to the following formula: to the output of the error amplifi er. TJ = TA + (PD)(68°C/W).
Note 6:
Load regulation is inferred by measuring the regulation loop gain.
Note 4:
This IC includes overtemperature protection that is intended
Note 7:
The QFN switch on-resistance is guaranteed by correlation to wafer to protect the device during momentary overload conditions. Junction level measurements. temperature will exceed 125°C when overtemperature is active. Continuous
Note 8:
Guaranteed by long-term current density limitations. operation above the specifi ed maximum operating junction temperature may impair device reliability.
TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current 300mA VREF vs Temperature at 2.25V, Switching Frequency vs Supply Channel. All Other Channels at 3.6V, 5.5V Voltage and Temperature 50% Peak Current
0.815 3.0 100 CHANNEL 200A ILOAD CHANNEL 100 = 50mA I 90 LOAD = 100mA ALL CHANNELS OPERATING 0.810 ALL CHANNELS OPERATING 80 70 0805 2.5 60 (V) 0.800 50 REFV 40 VIN = 3.6V 0.795 2.0 EFFICIENCY (%) TA = 25°C 30 VOUT100 = 1.2V fOSC –40°C 20 VOUT200A = 0.8V 0.790 V SWITCHING FREQUENCY (MHz) f IN = 2.25V OSC 0°C VOUT200B = 1.5V V f IN = 3.6V OSC 25°C 10 VOUT300 = 1.8V V f IN = 5.5V OSC 80°C ALL OTHER CHANNELS LOADED 50% 0.785 1.5 0 –50 0 50 100 2 3 4 5 6 0.0001 0.001 0.01 0.1 1 TEMPERATURE (°C) SUPPLY VOLTAGE (V) LOAD CURRENT 300mA CHANNEL (A) 3544B G03 3544 G01 3544 G02
Burst Mode Operation Burst Mode Operation Burst Mode Operation 300mA Channel 200mA, A-B Channels 100mA Channel
VOUT300 VOUT200B VOUT100 50mV/DIV 50mV/DIV 50mV/DIV AC AC AC COUPLED COUPLED COUPLED SW300 SW2B SW100 5V/DIV 5V/DIV 5V/DIV I I I L L L 50mA/DIV 50mA/DIV 100mA/DIV 3544 G04 3544 G05 3544 G06 2μs/DIV 2μs/DIV 2μs/DIV VIN = 3.6V TA = 25°C VIN = 3.6V TA = 25°C VIN = 3.6V TA = 25°C VOUT = 1.8V ILOAD = 20mA VOUT = 1.5V ILOAD = 15mA VOUT = 1.2V ILOAD = 12mA 3544fa 4
