Datasheet

ADC1213D_SER All information provided in this document is subject to legal disclaimers. © NXP B.V. 2011. All rights reserved.
Product data sheet Rev. 7 — 9 June 2011 15 of 42
NXP Semiconductors
ADC1213D series
Dual 12-bit ADC; serial JESD204A interface
11.1.3 Transformer
The configuration of the transformer circuit is determined by the input frequency. The
configuration shown in Figure 8
would be suitable for a baseband application.
The configuration shown in Figure 9 is recommended for high frequency applications. In
both cases, the choice of transformer is a compromise between cost and performance.
Table 9. RC coupling versus input frequency - typical values
Input frequency (MHz) Resistance () Capacitance (pF)
32512
70 12 8
170 12 8
Fig 8. Single transformer configuration
Fig 9. Dual transformer configuration
005aaa070
100 nF100 nF
100 nF
100 nF
100 nF
25 Ω
25 Ω
25 Ω
25 Ω
12 pF
ADT1-1WT
100 nF
Analog
input
INAP
INBP
INAM
INBM
VCM
005aaa071
100 nF
100 nF
100 nF
100 nF
12 Ω
12 Ω
8.2 pF
50 Ω
50 Ω
50 Ω
50 Ω
ADT1-1WTADT1-1WT
Analog
input
INAP
INBP
INAM
VCM
INBM