LTC1473L datasheet(11/16 Pages) LINER

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LTC1473L

VGG Regulator Inductor and Capacitors

The VGG regulator provides a power supply voltage signifi-

cantly higher than either of the two main power source

voltages to allow the control of N-channel MOSFET

switches. This micropower, step-up voltage regulator is

main power sources for maximum regulator efficiency.

APPLICATIO S I FOR ATIO

Three external components are required by the VGG regu-

lator: L1, C1 and C2, as shown in Figure 5.

L1 is a small, low current, 1mH surface mount inductor. C1

provides filtering to the input of the 1mH switched induc-

tor and should be at least 1

µF to filter switching transients.

The VGG output capacitor, C2, provides storage and filter-

ing for the VGG output and should be at least 1µF and rated

for 25V operation. C1 and C2 can be ceramic capacitors.

Figure 5. VGG Step-Up Switching Regulator

BAT1

DCIN

VGG

SWITCHING

REGULATOR

V+

GND

1473 F05

VGG

L1*

1mH

µF

25V

µF

25V

TO GATE

DRIVERS

(8.5V + V+)

LTC1473L

*COILCRAFT 1812LS-105 XKBC. (708) 639-6400

LTC1473L Datasheet(PDF) 11 Page - Linear Technology