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dc2432af

DEMO MANUAL DC2432A

Information furnished by Linear Technology Corporation is believed to be accurate and reliable.

However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa-

tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.

JP3: OD Output Disable:

1. ENA: Enables the outputs

2. DIS/EXT: Disables the outputs or allows the OD pin to

be driven externally.

JP4: Noise Reduction Select:

1. LF: 10μF

2. NF: Optional cap

3. HF: 0.1μF

JP5: OUT1 Select:

1. Fixed: OUT1 sense line is shorted to OUT1 Force and

the output is fixed.

2. ADJ: OUT1 sense line is separated from OUT1 Force

allowing for resistors R1 and R2 to be installed and

programming the OUT1 voltage to a different value.

JP6: OUT2 Select:

1. Fixed: OUT2 sense line is shorted to OUT2 Force and

the output is fixed.

2. ADJ: OUT2 sense line is separated from OUT2 Force

allowing for resistors R4 and R5 to be installed and

programming the OUT2 voltage to a different value.

QUICK START PROCEDURE

OPTIONAL SETTINGS

1. Programming the Output Voltage

using 2 resistors to create a divider in the feedback of

the output amplifier, the reference output can be pro-

grammed from 2.5V to 6V. The output voltage range

is limited on the high side due to internal ESD clamps

that protect the pins when the voltage goes above 6V.

The output voltage can be set using the equation:

The resistors will affect the temperature drift and

accuracy of the LT6658 output, so care should be

given when choosing resistors. It is crucial that the

resistor ratio stay consistent over temperature to

guarantee the best reference performance.

2. Setting the Noise Reduction

Thenoisereductionpincanbeusedtofilterthereference

output. The demo board comes with two pre-installed

capacitors that can be selected with the NR jumper. The

effects of the different capacitors are shown in Figure 2.

Figure 2

FREQUENCY (kHz)

0.01

0.1

1

10

100

1000

0

50

100

150

200

250

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