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DAC5668/88/89 Hardware Description

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• No VCXO installed. CDCM7005 in buffer mode which requires an input single-ended clock signal to

SMA connector J20.

• The DAC outputs are set by default to drive the TRF3703.

• The converter is set to operate with internal reference. Jumper J5 EXTLO is installed between pins 1

and 2.

• Full-scale output current set to 20 mA through RBIAS resistor R91.

4.1 Jumper Settings

The DAC5668/88/89EVM has onboard jumpers that allow the user to modify the board configuration.

Table 2 explains the functionality of the jumpers.

Table 2. Jumper List

JUMPER LABEL FUNCTION DEFAULT SETTING

CONDITION

SW1 BRD_RESET Resets the DAC and CDCM7005 devices

JP1 REF_CLK Chooses internal 10-MHz ref or external ref Internal Ref Pin 2-3

J1 VCXO_EN VCXO power down Disabled Unpopulated

JP2 VCXOB Chooses internal VCXO or external source External source Pin 2-3

JP3 VCXO Chooses internal VCXO or external source External source Pin 2-3

JP4 CLK1/CLKOUT Selects between CLK1 input to DAC or CLKOUT DAC CLKOUT Pin 2-3

output

JP5 CLK1C/LOCK Selects between CLK1C input to DAC or LOCK LOCK Pin 2-3

indicator DAC output

JP6 VFUSE Factory use only. Connect to 1.8VDD for normal 1.8 VDD Pin 1-2

operation.

J5 EXTLO Internal (GND) or external (3.3V) voltage reference Internal Reference Pin 1-2

CDC_PD Active-low power down of CDCM7005 Active CDCM7005 Pin 2-3

RESET DAC RESET Signal Unpopulated

CLKOUT_EN Active-low enable of CLKOUT signal buffer Enabled Buffer Pin 1-2

SYNC DAC SYNC Signal GND Pin 1-2

TX_ENABLE DAC TX_ENABLE Signal 3.3V Pin 2-3

4.2 Input/Output Connectors

Table 3 lists the input and output connectors on the DAC5668/88/89EVM.

Table 3. Input and Output Connections

REFERENCE LABEL CONNECTOR DESCRIPTION

DESIGNATOR TYPE

J2 34-pin Header A-bus input data to the DAC.

J3 IOUTB1 SMA Optional IOUTB1 output.

J4 IOUTB2 SMA DACB transformer output. Optional IOUTB2 output.

J6 RFOUT SMA RF output from TRF3703.

J7 34-pin Header B-bus input data to the DAC.

J8 IOUTA1 SMA Optional IOUTA1 output.

J9 IOUTA2 SMA DACA transformer output. Optional IOUTA2 output.

J10/J11 +5V Banana Plug +5-V connection pair. Required only for RF measurements.

J12 USB_CONN USB USB connector for software communication.

J13/J14 +1.8V Banana Plug +1.8-V connection pair.

J15/J16 3.3V Banana Plug +3.3-V connection pair.

J17 OUTCLK2 Y3A SMA Optional CDCM7005 clock output.

J18 OUTCLK2 Y4A SMA Optional CDCM7005 clock output.

DAC5668/88/89EVM SLAU241A–June 2008–Revised March 2010

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