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dc1903af

DEMO MANUAL DC1903A

Quick start proceDure

Figure 2. Demo Board Setup

Demonstration circuit 1903A is easy to set up and evalu-

ate the performance of the LTM2889. Refer to Figure 2

for proper measurement equipment setup and follow the

procedure below.

NOTE: When measuring the input or output voltage ripple

or high speed signals, care must be taken to avoid a long

ground lead on the oscilloscope probe.

1. Place jumpers in their default positions:

JP1 ON in the ON position

JP2 Silent in the OFF position

JP3 RE in the ON position

JP4 VCC2 in the 5V position

JP5 Slew in the FAST position

JP6 Split in the ON position

JP7 Termination in the ON position

2. With power off, connect the input power supply to VCC

and GND on pin header J1.

3. Turn on the power supply.

NOTE: Make sure that the input voltage does not exceed

6V.

4. Check for the proper output voltage. VCC2 = 5V between

test points V2 and G2.

5.Oncetheproperoutputvoltagesareestablished,connect

a function generator to terminal TXD and set to square

wave with a low of 0V, high = VCC, termination is Hi-Z.

Set frequency to 500kHz (1Mbps). Enable output of

function generator.

6. Connect oscilloscope to terminal RXD and observe

waveform at 500kHz. This demonstration shows data

that is transmitted from TXD, loops back through CANH

and CANL, and out of RXD.

POWER

SUPPLY

FUNCTION

GENERATOR

OSCILLOSCOPE

VIN

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