Purpose
1-2
1.1
Purpose
The DAC5674 EVM provides a platform for evaluating the DAC5674
digital-to-analog converter (DAC) under various signal, reference, and supply
conditions. This document should be used in combination with the EVM
schematic diagram supplied.
1.2
EVM Basic Functions
Digital inputs to the DAC can be provided with CMOS level signals up to
200 MSPS through a 40-pin header. This enables the user to provide
high-speed digital data to the DAC5674.
The analog output from the DAC is available via SMA connectors. Because
of its flexible design, the analog output of the DAC5674 can be configured to
drive a 50-
Ω
terminated cable using a 4:1 or 1:1 impedance ratio transformer,
or single-ended referred to GND.
The EVM allows for different clock configurations. The user can input a
differential ECL/PECL or TTL/CMOS level signal, to be used to generate a
single-ended or differential clock source. See the clock section for proper
configuration and operation.
Power connections to the EVM are via banana jack sockets. Separate sockets
are provided for the analog, digital, PLL, and I/O supply.
In addition to the internal bandgap reference provided by the DAC5674 device,
options on the EVM allow external reference to be provided to the DAC.
1.3
Power Requirements
The demonstration board has four power inputs. The first, +3.3VA, is required
to be +3.3 Vdc at banana jack J9 with the return going to J11. This is the analog
supply for the DAC5674. The second, +1.8 VD, is required to be +1.8 Vdc at
banana jack J14 with the return to J16. This is the d1.8-V supply for the
DAC5674. The third, +3.3VCLK, is required to be +3.3 Vdc at banana jack J10
with the return at J13. This is the digital supply for the internal PLL circuitry. The
fourth, +1.8/3.3VD_IO, is required to be 1.8 or +3.3 Vdc at banana jack
J12 with the return at J15. This is the supply for the digital I/Os. The EVM can
be powered using only two supplies, but powering from four separate supplies
provides higher performance.
Note:
Voltage Limits
Exceeding the maximum input voltages can damage EVM components.
Undervoltage may cause improper operation of some or all of the EVM
components.
