TSH70,71,72,73,74,75

Testing Conditions

23/33

5.4

Precautions when operating on an asymmetrical supply

The TSH7X can be used with either a dual or a single supply. If a single supply is used, the

designed, in order to reject any noise present on the supply rail.

As the bias current is 15uA, you must carefully choose the resistance R1 so as not to

introduce an offset mismatch at the amplifier inputs.

Figure 49. Schematic of asymmetrical (single) supply

R1 = 10K

Ω is a typical and convenient value. C1, C2, C3 are bypass capacitors that filter

and C2 = C3 = 100uF.

R2, R3 are such that the current through them must be greater than 100 times the bias

current. Therefore, we set R2 = R3 = 4.7K

Ω.

Diff Gain Step1

-0.5

-0.3

%

Diff Gain Step2

-0.7

-0.6

%

Diff Gain Step3

-0.3

-0.5

%

Diff Gain Step4

-0.1

-0.3

%

Diff Gain Step5

-0.4

-0.5

%

Diff Phase pos

0

0.1

deg

Diff Phase neg

-0.2

-0.4

deg

Diff Phase pp

0.2

0.5

deg

Diff Phase Step1

-0.2

-0.4

deg

Diff Phase Step2

-0.1

-0.4

deg

Diff Phase Step3

-0.1

-0.3

deg

Diff Phase Step4

0

0.1

deg

Diff Phase Step5

-0.2

-0.1

deg

Table 7.

Video results

Parameter

Value

Value

Unit

IN

R1

Vcc+

OUT

R2

R3 C1

C3

C2

+

-

Cf

R5

R4