LT3469

1

3469f

Amplifier

s

Current Limit:

±40mA Typical

s

Input Common Mode Range: 0V to 10V

s

s

Differential Gain Stage with High Impedance Output

s

s

Unloaded Gain: 30,000 Typical

Switching Regulator

s

s

Wide Operating Supply Range: 2.5V to 16V

s

High Switching Frequency: 1.3MHz

s

Internal Schottky Diode

s

Tiny External Components

s

Current Mode Switcher with Internal Compensation

s

Low Profile (1mm) SOT-23 Package

Piezo Microactuator Driver

with Boost Regulator

s

Piezo Speakers

s

Piezo Microactuators

s

Varactor Bias

, LTC and LT are registered trademarks of Linear Technology Corporation.

+

–

+IN

35

6

2

4

1

8

7

GND

FB

SW

LT3469

453k

16.5k

0.47

µF

50V

1V TO 33V

PIEZO

ACTUATOR

5nF < C < 300nF

10k

+

–

9.09k

100k

47

µH

–IN

OUT

3469 TA03

5V OR 12V

INPUT

0V TO 3V

1

µF

16V

The LT

drive outputs up to 33V from a 5V or 12V supply. An

internal switching regulator generates a boosted supply

capacitive loads in the range of 5nF to 300nF. Slew rate is

limited only by the maximum output current. The 35V

output voltage capability of the switching regulator, along

with the high supply voltage of the amplifier, combine to

allow the wide output voltage range needed to drive a

piezoceramic microactuator.

The LT3469 switching regulator switches at 1.3MHz,

allowing the use of tiny external components. The output

capacitor can be as small as 0.22

µF, saving space and cost

versus alternative solutions.

The LT3469 is available in a low profile ThinSOT

ThinSOT is a trademark of Linear Technology Corporation.

Piezo Microactuator Driver

Response Driving a 33nF Load

100mA/DIV

10V/DIV

INPUT

5V/DIV

50

µs/DIV

3469 TA04

FEATURES

DESCRIPTIO

APPLICATIO S

TYPICAL APPLICATIO