Datasheet LT3493-3 (Analog Devices)

LT3493-3 1.2A, 750kHz Step-Down Switching Regulator in 2mm × 3mm DFN
U FEATURES DESCRIPTIO
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Wide Input Range: 6.8V to 36V Operating,
The LT®3493-3 is a current mode PWM step-down DC/DC
40V Maximum
converter with an internal 1.75A power switch. The wide ■
1.2A Output Current
operating input range of 6.8V to 36V (40V maximum) makes ■
Fixed Frequency Operation: 750kHz
the LT3493-3 ideal for regulating power from a wide vari- ■ Output Adjustable Down to 780mV ety of sources, including unregulated wall transformers, ■ Short-Circuit Robust 24V industrial supplies and automotive batteries. Its high ■ Uses Tiny Capacitors and Inductors operating frequency allows the use of tiny, low cost induc- ■ Soft-Start tors and ceramic capacitors, resulting in low, predictable ■ Internally Compensated output ripple. ■ Low Shutdown Current: <2µA Cycle-by-cycle current limit provides protection against ■ Low VCESAT Switch: 330mV at 1A shorted outputs and soft-start eliminates input current ■ Thermally Enhanced, Low Profile 2mm × 3mm surge during start-up. The low current (<2µA) shutdown DFN-6 Package mode provides output disconnect, enabling easy power
U
management in battery-powered systems.
APPLICATIO S
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. ■ Automotive Battery Regulation All other trademarks are the property of their respective owners. ■ Industrial Control Supplies ■ Wall Transformer Regulation ■ Distributed Supply Regulation ■ Battery-Powered Equipment
U TYPICAL APPLICATIO 3.3V Step-Down Converter Efficiency
90 V V OUT IN V 3.3V 85 6.8V TO 36V IN BOOST 1.2A, V LT3493-3 0.1µF IN > 12V 10µH 1.1A, V 80 IN > 8V ON OFF SHDN SW 75 32.4k 22pF GND FB 70 10µF 1µF 10k EFFICIENCY (%) 65 60 3493-3 TA01a VIN = 12V 55 VOUT = 3.3V L = 10µH 50 0 0.2 0.4 0.6 0.8 1.0 1.2 LOAD CURRENT (A) 3493-3 TA01b 3493-3f 1