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dc2326af
DEMO MANUAL DC2326A
Description
LTC2345
16-/18-Bit, Octal 200ksps, SAR ADC
Demonstration circuit 2326A shows the proper way to drive
the
LTC
®
2345
ADC. The LTC2345 is a low noise, high speed,
simultaneous sampling 16-/18-bit successive approximation
register (SAR) ADC. The LTC2345 has a flexible SoftSpan
™
interface that allows conversion-by-conversion control of
the input voltage span on a per-channel basis. An internal
2.048V reference and 2
×
buffer simplify basic operation
while an external reference can be used to increase the
input range and the SNR of the ADC.
The DC2326A demonstrates the DC and AC performance of
the LTC2345 in conjunction with the DC590/DC2026 and
DC890 data collection boards. Use the DC590/DC2026 to
L
, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and PScope,
QuikEval and SoftSpan are trademarks of Linear Technology Corporation. All other trademarks
are the property of their respective owners.
assembly options
boarD photo
demonstrate DC performance such as peak-to-peak noise
and DC linearity. Use the DC890 if precise sampling rates
are required or to demonstrate AC performance such as
SNR, THD, SINAD and SFDR. The DC2326A is intended
to demonstrate recommended grounding, component
placement and selection, routing and bypassing for this
ADC. A suggested driver circuit for the analog inputs is
also presented.
Design files for this circuit board including the schematic,
layout and BOM are available at
http://www.linear.com/demo/DC2326A
Figure 1. DC2326A Connection Diagram
Assembly
Version
U1 Part Number
Max Conversion
Rate
Number of
Channels
Number of
Bits
Max CLK IN
Frequency
CLK IN/fs
Ratio
DC2326A-A
LTC2345-18
200ksps
8
18
60MHz
300
DC2326A-B
LTC2345-16
200ksps
8
16
60MHz
300
–9V
V
IN2
0V to 4.096V
V
IN1
0V to 4.096V
CLK
100MHz MAX
2.5V
P-P
+9V
DC890
DC590 OR DC2026
GND
