Quick Start Procedure - Analog Devices DC2837A-A Demo Manual

DEMO MANUAL
DC2837A-A/DC2837A-B

QUICK START PROCEDURE

Demonstration circuit 2837A is easy to set up to evaluate
the performance of the LTC2063/LTC2066. The DC2837A
board provides multiple empty mostly-0805 component
footprints for users to configure the LTC2063/LTC2066
as desired.
The default configuration of the board is in unity gain/
buffer with split supplies (V
Refer to Figure 1 for a generic schematic, Figure 2 for
measurement equipment setup, and Table 1 for a jumper
table, and follow the procedure below.
Note: Unless otherwise specified, leave jumpers in
default positions, and components unstuffed. Table 1
explains each jumper setting in further detail.
1. Verify that jumper JP6 for SHDN is on position 1,
labeled EN, so that the part is enabled.
2. Verify that jumper JP4 is across 2–3 for GND so the
board is in split supply mode.
3. Set the power supply's positive output to +2.5V and
the negative output to –2.5V.
Note: The supply limits are ±2.62V in split sup-
ply, and 1.7V to 5.25V in single-supply (V
configuration.
4. With power off, connect the power supply to the row
of turrets at the top of the board: + supply to V
–
ret, –supply to V turret, and COM to GND turret.
5. Connect a signal generator either at the +IN and GND
turrets or at the +IN SMA input. A 100Hz sine wave
with 0V offset and 0.5V
Note: The input lowpass filter at IN
of 480Hz for DC2837A-A (LTC2063) and 2.4kHz
for DC2837A-B (LTC2066).
6. Connect an Oscilloscope 10× probe to the OUT turret.
Clip scope probe GND to a GND turret. Set the scaling
to 100mV/2ms per division.
2
+ –
and V ).
–
= GND)
+
is a good starting point.
P-P
+
has a cutoff
7. Power-up the system. A 100Hz 0.5V
centered at 0V should appear on the oscilloscope.
8. Increase the signal amplitude and observe the signal
for clipping as signals reach the supply rails. Slew
and settling behavior can be evaluated by switching
the signal generator to square wave.
9. To evaluate shutdown performance, move the jumper
at JP6 to position 3, labeled DIS, tying SHDN to V
To re-enable the part, move the JP6 jumper back to
EN (position 1).
10. OPTIONAL: To evaluate shutdown performance with
a shutdown control signal, remove any jumper con-
nectors on JP6 completely. Connect a signal gen-
erator to the SHDN turret and GND. Set the signal
generator to a 5V
Keep the input sine wave on. Adjust oscilloscope
time scale to 100ms/div at least. Observe the part's
output shutting down and returning, and the supply
current dropping when shut down and rising again
when turned back on.
Table 1. Jumper Table
POSITION 1
JUMPER OR STUFFED*
+
JP1 V
tur-
JP2* Ties –IN to V
–
or V via Z1
+
JP3 V
–
JP4 V Tied to GND
(Single-Supply)
JP5 Add Z2 in
Parallel with R5
Feedback
+
JP6 V , Enable
* Two-Terminal Jumper ONLY (JP2)
P-P
, 0V offset, 1Hz square wave.
P-P
POSITION 3
OR UNSTUFFED*
–
V Add DC Offset, or
Connects Filter
Component Z1 to –IN
+
Disconnects Z1 Unstuffed by Default
+
–IN from V or
–
V via Z1
–
V Add DC Offset to +IN;
R9, R10 Allow for
Scaling/Dividing
Separate 3rd Position GND for
–
V and GND Jumper Storage when
(Split Rail) Using Split Rails
Short Out R6 Default Open Path
in Series with (Z2 Unstuffed)
Output
–
V , Disable Remove Jumper
Completely if Using
External SHDN Control
sine wave
–
.
NOTES
Rev. 0