Datasheet LT3470A (Analog Devices)
| Manufacturer | Analog Devices |
| Description | Micropower Buck Regulator with Integrated Boost and Catch Diodes |
| Pages / Page | 20 / 1 — FEATURES. DESCRIPTION. Low Quiescent Current: 35μA at 12VIN to 3.3VOUT. … |
| File Format / Size | PDF / 207 Kb |
| Document Language | English |
FEATURES. DESCRIPTION. Low Quiescent Current: 35μA at 12VIN to 3.3VOUT. Integrated Boost and Catch Diodes
Model Line for this Datasheet
LT3470A
Text Version of Document
LT3470A Micropower Buck Regulator with Integrated Boost and Catch Diodes
FEATURES DESCRIPTION
n
Low Quiescent Current: 35μA at 12VIN to 3.3VOUT
The LT®3470A is a micropower step-down DC/DC con- n
Integrated Boost and Catch Diodes
verter that integrates a 440mA power switch, catch diode n
Input Range: 4V to 40V
and boost diode into low profile 2mm × 3mm DFN n
3.3V at 250mA from 4V to 40V Input
package. The LT3470A combines Burst Mode and n
5V at 250mA from 5.7V to 40V Input
continuous operation to allow the use of tiny inductor n
Low Output Ripple: <10mV
and capacitors while providing a low ripple output to n < 1μA in Shutdown Mode loads of up to 250mA. n Output Voltage: 1.25V to 16V With its wide input range of 4V to 40V, the LT3470A can n Hysteretic Mode Control regulate a wide variety of power sources, from 2-cell Li-Ion – Low Ripple Burst Mode® Operation at Light Loads batteries to unregulated wall transformers and lead-acid – Continuous Operation at Higher Loads batteries. Quiescent current in regulation is just 35μA in n Solution Size as Small as 50mm2 a typical application while a zero current shutdown mode n Low Profile (0.75mm) 2mm × 3mm Thermally disconnects the load from the input source, simplifying Enhanced 8-Lead DFN Package power management in battery-powered systems. Fast cur- rent limiting and hysteretic control protects the LT3470A
APPLICATIONS
and external components against shorted outputs, even at 40V input. The LT3470A has higher output current and n Automotive Battery Regulation improved start-up and dropout performance compared n Power for Portable Products to the LT3470. n Distributed Supply Regulation L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks n Industrial Supplies of Linear Technology Corporation. All other trademarks are the property of their respective n Wall Transformer Regulation owners.
TYPICAL APPLICATION Efficiency and Power Loss vs Load Current
90 1000 V V IN IN = 12V 5.7V TO 40V 80 0.22μF VIN BOOST 70 100 POWER LOSS (mW) LT3470A 33μH VOUT OFF ON SHDN SW 5V 60 250mA BIAS 604k 50 10 22pF 1% 2.2μF FB 22μF 40 EFFICIENCY (%) GND 200k 1% 30 1 3470a TA01a 20 10 0.1 0.1 1 10 100 300 LOAD CURRENT (mA) 3470a TA01b 3470afb 1
FEATURES DESCRIPTION
n
Low Quiescent Current: 35μA at 12VIN to 3.3VOUT
The LT®3470A is a micropower step-down DC/DC con- n
Integrated Boost and Catch Diodes
verter that integrates a 440mA power switch, catch diode n
Input Range: 4V to 40V
and boost diode into low profile 2mm × 3mm DFN n
3.3V at 250mA from 4V to 40V Input
package. The LT3470A combines Burst Mode and n
5V at 250mA from 5.7V to 40V Input
continuous operation to allow the use of tiny inductor n
Low Output Ripple: <10mV
and capacitors while providing a low ripple output to n < 1μA in Shutdown Mode loads of up to 250mA. n Output Voltage: 1.25V to 16V With its wide input range of 4V to 40V, the LT3470A can n Hysteretic Mode Control regulate a wide variety of power sources, from 2-cell Li-Ion – Low Ripple Burst Mode® Operation at Light Loads batteries to unregulated wall transformers and lead-acid – Continuous Operation at Higher Loads batteries. Quiescent current in regulation is just 35μA in n Solution Size as Small as 50mm2 a typical application while a zero current shutdown mode n Low Profile (0.75mm) 2mm × 3mm Thermally disconnects the load from the input source, simplifying Enhanced 8-Lead DFN Package power management in battery-powered systems. Fast cur- rent limiting and hysteretic control protects the LT3470A
APPLICATIONS
and external components against shorted outputs, even at 40V input. The LT3470A has higher output current and n Automotive Battery Regulation improved start-up and dropout performance compared n Power for Portable Products to the LT3470. n Distributed Supply Regulation L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks n Industrial Supplies of Linear Technology Corporation. All other trademarks are the property of their respective n Wall Transformer Regulation owners.
TYPICAL APPLICATION Efficiency and Power Loss vs Load Current
90 1000 V V IN IN = 12V 5.7V TO 40V 80 0.22μF VIN BOOST 70 100 POWER LOSS (mW) LT3470A 33μH VOUT OFF ON SHDN SW 5V 60 250mA BIAS 604k 50 10 22pF 1% 2.2μF FB 22μF 40 EFFICIENCY (%) GND 200k 1% 30 1 3470a TA01a 20 10 0.1 0.1 1 10 100 300 LOAD CURRENT (mA) 3470a TA01b 3470afb 1
