Datasheet LT3463, LT3463A (Analog Devices)

LT3463/LT3463A Dual Micropower DC/DC Converters with Schottky Diodes
U FEATURES DESCRIPTIO
■
Generates Well-Regulated Positive and
The LT®3463/LT3463A are dual micropower DC/DC con-
Negative Outputs
verters with internal Schottky diodes in a 10-lead 3mm × ■
Low Quiescent Current:
3mm DFN package. Negative and positive LT3463 con-
20
µ
A (per Converter) in Active Mode
verters have a 250mA current limit. The LT3463A positive
<1
µ
A in Shutdown Mode
converter also has a 250mA limit, while the negative ■
Internal 42V Power Switches
converter has a 400mA limit. Both devices have an input ■
Internal 42V Schottky Diodes
voltage range of 2.4V to 15V, making them ideal for a wide ■ Low V variety of applications. Each converter features a quies- CESAT Switch: 180mV at 150mA ■ Input Voltage Range: 2.4V to 15V cent current of only 20µA, which drops to under 1µA in ■ High Output Voltages: Up to ±40V shutdown. A current limited, fixed off-time control scheme ■ Low Profile (0.8mm) 3mm x 3mm DFN Package conserves operating current, resulting in high efficiency over a broad range of load current. The 42V switch enables
U
high voltage outputs up to ±40V to be easily generated
APPLICATIO S
without the use of costly transformers. The low 300ns off- ■ CCD Bias time permits the use of tiny, low profile inductors and ■ LCD Bias capacitors to minimize footprint and cost in space-con- ■ Handheld Computers scious portable applications. ■ Digital Cameras , LTC and LT are registered trademarks of Linear Technology Corporation.
U TYPICAL APPLICATIO CCD Bias Supply (15V, –8V) Efficiency and Power Loss
10µH V V 80 240 IN OUT1 V 2.7V 15V IN = 3.6V 15V EFFICIENCY TO 5V 10mA 1M 75 200 4.7µF 2.2µF POWER LOSS (mW) VIN SW1 VOUT1 90.9k 70 160 –8V EFFICIENCY SHDN1 FB1 LT3463A 65 120 VREF SHDN2 FB2 154k EFFICIENCY (%) 60 80 GND SW2 D2 15V LOSS 55 40 –8V LOSS 1M 10pF 1µF 10µH 50 0 VOUT2 0.1 1 10 100 –8V LOAD CURRENT (mA) 50mA 4.7µF 3463 TA01b 3463 TA01a 3463f 1