ADC1112D125 Datasheet, PDF (18/39 Pages) NXP Semiconductors – Dual 11-bit ADC; CMOS or LVDS DDR digital outputs

Integrated Device Technology
ADC1112D125
Dual 11-bit ADC: CMOS or LVDS DDR digital outputs
INAP/
R
INBP
C
INAM/
R
INBM
Fig 17. Anti-kickback circuit
001aan679
The component values are determined by the input frequency and should be selected so
as not to affect the input bandwidth.
Table 11. RC coupling versus input frequency, typical values
Input frequency (MHz)
R ()
3
25
70
12
170
12
C (pF)
12
8
8
11.2.3 Transformer
The configuration of the transformer circuit is determined by the input frequency. The
configuration shown in Figure 18 would be suitable for a baseband application.
ADT1-1WT
Analog
input
100 nF
100 nF
100 nF
100 nF
100 nF
25 Ω
25 Ω
25 Ω
25 Ω
INAP/INBP
12 pF
INAM/INBM
VCMA/VCMB
100 nF
005aaa094
Fig 18. Single transformer configuration suitable for baseband applications
The configuration shown in Figure 19 is recommended for high frequency applications. In
both cases, the choice of transformer is a compromise between cost and performance.
ADC1112D125 3
Product data sheet
Rev. 03 — 2 July 2012
© IDT 2012. All rights reserved.
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