Analog Inputs - Analog Devices EVAL-ADAQ4003FMCZ User Manual

UG-1533

ANALOG INPUTS

The analog inputs of the EV-ADAQ4003PMDZ, J1 and J2, are
Subminiature Version B (SMB) connectors. These inputs are
fed to the ADA4898-1. J1 and J2 are buffered with dedicated
amplifier circuitry, U4 and U7, as shown in Figure 34. The
circuit enables different configurations, input range scaling,
filtering, amplifiers and supplies, and the addition of a dc
component. The analog input amplifiers are set as unity-gain
buffers at the factory.
Table 2. Jumper Details with Factory Default Setting
Link Default
JP1 Not populated
JP2 B1 and B2, A1 and A2
JP3 B1 and B2, A1 and A2
JP4 Pin A to Pin COM
JP5 Pin A to Pin COM
JP6 Pin A to Pin COM
JP6 Pin A to Pin COM
JP7 Pin B to Pin COM
JP8 Pin B to Pin COM
JP9 Pin B to Pin COM
JP10 Pin B to Pin COM
JP11 Pin A to Pin COM
JP12 Pin A to Pin COM
JP13 Pin A to Pin COM
JP14 Pin A to Pin COM
JP15 Pin A to Pin COM
EVAL-ADAQ4003FMCZ
Function
Gain options
µModule input
µModule input
Synchronize the switching frequency to CNV
Op amp or in-amp
Op amp or in-amp
Single-ended or differential input
Op amp or in-amp
Amplifier or in-amp
Gain setting pin (LSB)
Gain setting pin (MSB)
Power
Differential amplifier power mode
Differential amplifier power down
Reference buffer power down
Differential amplifier power down
Rev. 0 | Page 6 of 31
Evaluation Board User Guide
The analog inputs are fully differential by default. If a single-ended
bipolar input is desired, such as ±10 V, the EV-ADAQ4003PMDZ
can be configured for single-ended to differential conversion
by changing JP6 to Position 2 and Position 3 and by applying the
single-ended input at Connector J1 (see Table 2).
For dynamic performance, a fast Fourier transform (FFT) test
can be performed by applying a low distortion ac source. For
low frequency testing, the audio precision source, such as the
SYS-2700 series, can be used directly with the evaluation board.
Different precision sources can be used with additional filtering.
Comment
Fully differential or single-ended configuration.
The ADAQ4003 has a gain of 0.454 (20 V range). See the
ADAQ4003 data sheet for other gains.
The ADAQ4003 has a gain of 0.454 (20 V range). See the
ADAQ4003 data sheet for other gains.
To set the switching frequency to 1.2 MHz, pull the
SYNC/FREQ pin of the
Connect the J1 input to the ADA4898-1 op amp.
Connect the J2 input to the ADA4898-1 op amp.
Differential input by default. Connect Pin B to COM for a
single-ended input and connect JP7 to Pin B to Pin COM.
Connect the ADA4898-1 op amp to the ADAQ4003
µModule.
Connect Pin A to Pin COM to the output of the AD8251.
Refer to the AD8251 data sheet for the truth table logic
levels for transparent gain mode.
Refer to the AD8251 data sheet for the truth table logic
levels for transparent gain mode.
Differential amplifier positive supply. Tied to ground.
Differential amplifier positive supply. Tied to ground.
Full power mode. See the ADAQ4003 data sheet.
Powered up. See the ADAQ4003 data sheet.
Powered up. See the ADAQ4003 data sheet.
ADP5070 low or Pin B to Pin COM.