DAC1408D650_1008 Datasheet, PDF (34/98 Pages) NXP Semiconductors – Dual 14-bit DAC up to 650 Msps 2, 4 or 8 interpolating

NXP Semiconductors
DAC1408D650
DAC1408D; up to 650 Msps; 2×, 4× or 8× interpolating with JESD204A
10.13.2 DC interface to an Analog Quadrature Modulator (AQM)
When the system operation requires to keep the DC component of the spectrum, the
DAC1408D650 can use a DC interface to connect to an AQM. In this case, the offset
compensation for LO cancellation can be made with the use of the digital offset control in
the DAC.
Figure 22 provides an example of a connection to an AQM with a 1.7 V_i(cm) common mode
input level.
V_DDA(3V3)
AQM (V_i(cm) = 1.7 V)
(1)
IOUTnP
IOUTnN
51.1 Ω 51.1 Ω
0 mA to 20 mA
442 Ω
442 Ω
768 Ω
(2)
BBP
BBN
768 Ω
(1) _{IOUTnP/IOUTnN; Vo(cm) = 2.67 V; Vo(dif)(p-p) = 1.98 V}
(2) _{BBP/BBN; Vi(cm) = 1.7 V; Vi(dif)(p-p) = 1.26 V}
001aaj541
Fig 22. An example of a DC interface to a 1.7 V_i(cm) AQM
Figure 23 provides an example of a connection to an AQM with a 3.3 V_i(cm) common mode
input level.
V_DDA(3V3)
5V
AQM (V_i(cm) = 3.3 V)
(1)
IOUTnP
IOUTnN
54.9 Ω
54.9 Ω
237 Ω
237 Ω
1.27 kΩ 1.27 kΩ
750 Ω
750 Ω
(2)
BBP
BBN
(1) _{IOUTnP/IOUTnN; Vo(cm) = 2.75 V; Vo(dif)(p-p) = 1.97 V}
(2) _{BBP/BBN; Vi(cm) = 3.3 V; Vi(dif)(p-p) = 1.5 V}
001aaj542
Fig 23. An example of a DC interface to a 3.3 V_i(cm) AQM
The auxiliary DACs can be used to control the offset in a precise range or with precise
steps.
Figure 24 provides an example of a DC interface with the auxiliary DACs to an AQM with
a 1.7 V_i(cm) common mode input level.
DAC1408D650
Preliminary data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 02 — 11 August 2010
© NXP B.V. 2010. All rights reserved.
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