10

LT1792

S

APPLICATI

I FOR ATIO

also increases the parasitic gate capacitance, which if left

unchecked, can result in increased overshoot and ring-

ing. When the feedback around the op amp is resistive

create excess phase shift and even oscillation. A small

is completely removed.

Figure 5

1792 F05

OUTPUT

1792 TA06

TYPICAL OFFSET

≈ 0.8mV

1% TOLERANCES

= – 6dB AT f = 16.3Hz

LOWER RESISTOR VALUES WILL RESULT IN LOWER THERMAL NOISE AND LARGER CAPACITORS

R3

249k

C2

100nF

C1

33nF

R1

237k

R2

237k

R6

249k

C4

330nF

3

2

LT1792

6

C3

10nF

R4

154k

R5

154k

7

15V

–15V

4

6

3

2

LT1792

10Hz Fourth Order Chebyshev Lowpass Filter (0.01dB Ripple)

S

APPLICATI

TYPICAL

Accelerometer Amplifier with DC Servo

7

5V TO 15V

– 5V TO –15V

4

1792 TA03

OUTPUT

R1

100M

C1

1250pF

R3

2k

C3

2

µF

R2

18k

C2

2

µF

2

3

R4

20M

LT1792

6

R5

20M

ACCELEROMETER

B & K MODEL 4381

OR EQUIVALENT

6

3

2

LT1792

R4C2 = R5C3 > R1 (1 + R2/R3) C1

OUTPUT = 0.8mV/pC* = 8.0mV/g**

DC OUTPUT

≤ 2.7mV

OUTPUT NOISE = 6nV/

√Hz AT 1kHz

*PICOCOULOMBS

**g = EARTH’S GRAVITATIONAL CONSTANT