ADC32RF44 Datasheet, PDF (24/134 Pages) Texas Instruments – Dual-Channel, 14-Bit, 2.6-GSPS, Analog-to-Digital Converter

ADC32RF44
SBAS809 – FEBRUARY 2017
www.ti.com
Feature Description (continued)
The input impedance of analog inputs can also be modelled as parallel combination of equivalent resistance and
capacitance. Figure 60 and Figure 61 show how equivalent impedance (C_IN and R_IN) vary over frequency.
3
0.07
2
0.06
1
0.05
0
0.04
-1
0.03
-2
0.02
-3
0
500
1000 1500 2000 2500 3000
Input Frequency (MHz)
D063
Figure 60. Differential Input Capacitance vs
Input Frequency
0.01
0
500 1000 1500 2000 2500 3000
Input Frequency (MHz)
D06041
Figure 61. Differential Input Resistance vs Input Frquency
Each input pin (INP, INM) must swing symmetrically between (CM + 0.3375 V) and (CM – 0.3375 V), resulting in
a 1.35-V_PP (default) differential input swing. The input sampling circuit has a 3-dB bandwidth that extends up to
approximately 3.2 GHz, as shown in Figure 62.
2
1
0
-1
-2
-3
-4
-5
-6
-7
-8
100
100 Ohm Source
50 Ohm Source
200 300 500 700 1000 2000 3000 5000
Input Frequency (MHz)
D062
Figure 62. Input Bandwidth with a 100-Ω Source Resistance
24
Submit Documentation Feedback
Product Folder Links: ADC32RF44
Copyright © 2017, Texas Instruments Incorporated