Applications

Gain Setting

A single external resistor between the RG1 and

RG2 pins is all that is needed to set the gain of the

THAT 1510 / 1512, according to the formulae

for the 1510:

G

k

RG

=+

1

10

W

or

RG

k

G

=

-

10

1

W

for the 1512:

G

k

RG

=+

05

5

.

W

or

RG

k

G

5

05

W

.

For unity gain operation on the 1510, RG1 and

RG2 may be left open. RG should be set to 10k

W in

the 1512. To avoid excess noise and ensure tempera-

ture stability, non-inductive wirewound or metal-film

resistors are recommended for RG.

Total gain accuracy will depend on both the toler-

ance on RG, and on the gain equation accuracy of the

THAT 1510/1512.

Total gain drift will result from

the mismatch between the tempco of RG and the

THAT Corporation; 45 Sumner Street; Milford, Massachusetts 01757-1656; USA

Tel: +1 508 478-9200; Fax: +1 508 478-0990; Web: www.thatcorp.com

Page 4

THAT 1510 / 1512 Microphone Preamplifier

Preliminary Information

RG

+In

3

4

Out

6

7

5

-In

2

RG1

1

RG2

8

U1

THAT

1510/1512

-15

+15

-In

+In

R1

1k

R2

1k

C1

470p

C2

470p

C3

47p

Out

C6

100n

C9

100n

V+

V-

Ref

Figure 2. Basic 1510 / 1512 Circuit

RG

+In

3

4

Out

6

7

5

-In

2

RG1

1

RG2

8

U1

THAT 1510/1512

-In

+In

R1

1k

R2

1k

C1

470p

C2

470p

C3

47p

Out

3

2

6

U2

353

C8

100n

R3

510k

-15

+15

C6

100n

C9

100n

V+

V-

Ref

Figure 3. 1510 / 1512 Circuit with Output Offset Correction