User Guide

Hardware guide

Hardware configuration

The ADAQ8092 uModule soldered to the EVAL-ADAQ8092-FMCZ does not require an external supply to power up the board. It uses the +12 V supply from the carrier board (such as ZedBoard) and activates the on-board LDOs to provide the 3.3 V and 1.8 V supplies needed by the board.

On the ZedBoard, configure the BOOT switches (JP7-JP11) and the MIO0 jumper (JP6) for the desired boot mode, and set VADJ to 2.5 V as required by the HDL project. Refer to the ZED Quickstart guide for the specific jumper positions for SD card and JTAG boot modes.

Analog Inputs

Figure 1 Analog Input Circuitry of EVAL-ADAQ8092-FMCZ

The EVAL-ADAQ8092-FMCZ allows the user to use either a single-ended or differential source. For single-ended input, the user can either use the on-board balun to drive the part differentially, or bypass it to drive the part in single-ended mode. The input configuration is selected using jumper settings and 0 Ohm resistor placement.

Factory default settings (single-ended input)

Channel	Link	Location
1	JP1	Pin 2 to Pin 3
	JP3	Pin 2 to Pin 1
	JP4	Pin 2 to Pin 3
2	JP2	Pin 2 to Pin 3
	JP5	Pin 2 to Pin 1
	JP6	Pin 2 to Pin 3

Note

With the factory default settings, the board is ready for a single-ended source. If using a differential source instead, install 49.9 Ohm resistors at R1 (Channel 1) and R3 (Channel 2) to properly balance the inputs.

Differentially driven using the balun

Channel	Link	Location
1	JP1	Pin 2 to Pin 1
	JP3	Pin 2 to Pin 3
	JP4	Pin 2 to Pin 1
2	JP2	Pin 2 to Pin 1
	JP5	Pin 2 to Pin 3
	JP6	Pin 2 to Pin 1

Note

When using this configuration, resistor values must also be changed to properly balance the impedance and maintain a gain of approximately 5. For Channel 1: R8 and R9 = 200 Ohm, R14 and R16 = 18.2 Ohm. For Channel 2: R10 and R11 = 200 Ohm, R15 and R17 = 18.2 Ohm.

Encode circuitry

Figure 2 Encode Circuitry of EVAL-ADAQ8092-FMCZ

The board supports both single-ended and differential encode modes. The default configuration uses the single-ended encode mode, which requires a CMOS level signal. The board also provides an option to install an oscillator at Y1 as a built-in clock source for single-ended encode mode.

When using a sinusoidal, PECL, or LVDS signal, the differential encode mode is recommended.

Power supply

Figure 3 Power Circuitry of EVAL-ADAQ8092-FMCZ

The EVAL-ADAQ8092-FMCZ uses the +12 V supply from the carrier board at pin C35 of the FMC connector. The power distribution chain is:

• LTC4359 (U2): reverse input protection

• LTM8074 (U4): step-down regulator, configured for 5 V output

• LTC1673-1.8 (U3): provides VDD and OVDD supplies (1.8 V)

• LTC1763-3.3 (VR1): provides VCC supply (3.3 V)

The VADJ voltage provided from the carrier through the FMC connector must be set to 2.5 V. The VADJ value can be checked in the HDL project at ADAQ8092-FMC HDL project.

External supplies can also be used if some of the built-in power circuitry requires rework.

Schematic

The evaluation board schematic can be found at:

• EVAL-ADAQ8092-FMCZ Schematic