KH600AI datasheet(10/13 Pages) CADEKA

10 / 13 page

DATA SHEET

KH600

REV. 2 January 2004

Figure 14: Harmonic Distortion vs. Total Is

Trimming Differential Output Offset Voltage

Vary +Vb1 and +Vb2 to adjust differential offset voltage.

+Vb1 controls OUT1 and +Vb2 controls OUT2. The output

voltage moves in a direction opposite to the direction of the

bias voltage. Figure 15 shows the resulting voltage change at

OUT1 and OUT2 when the voltage on +Vb1 is changed.

Figure 16 shows the resulting voltage change at OUT1 and

OUT2 when the voltage on +Vb2 is changed. OUT1 and

OUT2 change at the same rate when -Vb is changed, as

shown in Figure 17. Therefore, changing the voltage on -Vb

has no effect on differential output offset voltage.

Figure 15: Output vs. +Vb1

Figure 16: Output vs. +Vb2

Figure 17: Output vs. -Vb

Adjusting Common Mode Output

Offset Voltage

Short +Vb1 to +Vb2 and vary +Vb and -Vb to adjust common

mode output offset voltage. The recommended values for

achieving a given output offset are shown in Figure 18. These

values were chosen to give the best distortion performance.

The exact values are not crucial.

Figure 18: Vb vs. Common Mode Voltage

For common mode voltages of 0 to -3.5V swap the Vb’s and

change the polarity. See the example below.

Figures 19 and 20 illustrate how the common mode voltage

effects harmonic distortion. Figure 21 shows the resulting Is

and -Is supply currents.

Pay close attention to your peak-to-peak output voltage

requirement. As you change the common mode voltage, you

may need to increase or shift ±Vs in order to achieve your

output requirements. A 2V margin is recommended. For

example, if your output requirement is 5Vpp and you will be

800

400

200

-600

+Vb2 (V)

-200

-400

600

OUT2

OUT1

800

400

200

-600

-Vb (V)

-8

-6

-2

-4

-200

-400

600

OUT1, OUT2

-12

-10

-8

-6

-4

-2

Common Mode Voltage (V)

-Vb

+Vb1, +Vb2

+Vs = +7.5V

-Vs = -3.5V

800

400

200

-600

+Vb1 (V)

-200

-400

600

OUT1

OUT2

-10

-50

-60

-70

-20

-30

-40

-80

-90

-100

Total Supply Current (mA)

100

140

120

3rd

2nd

5Vpp @ 50MHz

Desired Common

+Vb1 and +Vb2 (V)

-Vb (V)

Mode Voltage

2 Volts

-8

-2 Volts

-2

KH600AI Datasheet(PDF) 10 Page - Cadeka Microcircuits LLC.

KH600AI Datasheet(HTML) 10 Page - Cadeka Microcircuits LLC.

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13

Datasheet Download

Link URL