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dc1908af

DEMO MANUAL DC1908A

DC718 QUICK START PROCEDURE

DC590 SETUP

ASSEMBLY OPTIONS

Table 1. DC1908A Assembly Options

ASSEMBLY VERSION U1 PART NUMBER MAX CONVERSION RATE # OF BITS MAX CLK FREQUENCY

AIN+ RANGE

AIN– RANGE

DC1908A-A

LTC2338CMS-18

1Msps

18

62MHz

±10.24V

±10.24V

DC1908A-B

LTC2337CMS-18

500ksps

18

31MHz

±10.24V

±10.24V

DC1908A-C

LTC2336CMS-18

250ksps

18

15.5MHz

±10.24V

±10.24V

DC1908A-D

LTC2328CMS-18

1Msps

18

62MHz

±10.24V

Grounded Internally

DC1908A-E

LTC2327CMS-18

500ksps

18

31MHz

±10.24V

Grounded Internally

DC1908A-F

LTC2326CMS-18

250ksps

18

15.5MHz

±10.24V

Grounded Internally

DC1908A-G

LTC2328CMS-16

1Msps

16

50MHz

±10.24V

Grounded Internally

DC1908A-H

LTC2327CMS-16

500ksps

16

25MHz

±10.24V

Grounded Internally

DC1908A-I

LTC2326CMS-16

250ksps

16

12.5MHz

±10.24V

Grounded Internally

Check to make sure that all switches and jumpers are set

as shown in the connection diagram of Figure 1. The de-

fault connections configure the ADC to use the internal

reference. The analog input is DC coupled. Connect the

DC1908A to a DC718 USB high speed data collection

board using connector P1. Then, connect the DC718 to

a host PC with a standard USB A/B cable. Apply ±16V

to the indicated terminals. Then apply a low jitter signal

sine wave or square wave to CLK IN (J1). Note that CLK

IN has a 50Ω termination resistor to ground.

Run the PScope software (Pscope.exe version K72 or

later) supplied with the DC718 or download it from www.

linear.com/software.

Complete software documentation is available from the

Help menu. Updates can be downloaded from the Tools

menu. Check for updates periodically as new features

may be added.

The PScope software should recognize the DC1908A and

configure itself automatically.

Click the Collect button (See Figure 4) to begin acquiring

data. The Collect button then changes to Pause, which

can be clicked to stop data acquisition.

IMPORTANT!ToavoiddamagetotheDC1908AorDC590,

make sure that VCCIO (JP6) of the DC590 is set to 3.3V

before connecting the DC590 to the DC1908A.

To use the DC590 with the DC1908A, it is necessary to

apply ±16V and ground to the +16V, –16V and GND ter-

minals or disable amplifier U10 by moving R32 and R35

to R31 and R38 respectively. Disabling U10 will require

that both AIN+ and AIN– (J6) be driven with a low output

impedance signal source. Connect the DC590 to a host PC

with a standard USB A/B cable. Connect the DC1908A to a

DC590USBserialcontrollerusingthesupplied14-conduc-

tor ribbon cable. Apply a signal source to AIN+ or AIN+

and AIN– depending on how the DC1908A is configured.

Run the QuikEval software supplied with the DC590 or

download it from www.linear.com/software. The correct

control panel will be loaded automatically. Click the COL-

LECT button (See Figure 5) to begin reading the ADC.