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dc1794afa
DEMO MANUAL DC1794A
qUick stArt proceDUre
Figure 2. Demo Board Setup
Demonstration circuit 1794A is easy to set up and evalu-
ate the performance of the LTM2885. 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. Install jumpers in following positions: (all are default
except JP5 and JP6)
JP1 (TE pin) place in ON position
JP2 (DE pin) place in ON position
JP3 (
RE
pin) place in ON position
JP4 (ON pin) place in ON position
JP5 (
SLO
pin) place in OFF position
JP6 (Duplex header) place in HALF DUPLEX position
2. With power off, connect the input power supply to V
CC
and GND turrets.
3. Turn on the power at the input.
NOTE: Make sure that the input voltage does not exceed
6V.
4. Check for the proper output voltage. V
CC2
= 5V, this can
be measured between probe points V
CC2
and GND2.
5. Once the proper output voltage is established, connect a
function generator to TXD turret and set to square wave
with a low of 0V, high = V
CC
. Set frequency to 10MHz
(20Mbps). Enable output of function generator.
6. Connect oscilloscope to RXD turret and observe 10MHz
waveform. This demonstration shows data that is
transmitted from TXD, loops back through half-duplex
connection, and out of RXD.
VIN
OSCOPE
FUNCTION
GENERATOR
+
–
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