ADC32RF44IRMPR datasheet(123/135 Pages) TI2

123 / 135 page

Frequency (MHz)

260

520

780

1040

1300

-120

-100

-80

-60

-40

-20

D001

Frequency (MHz)

260

520

780

1040

1300

-120

-100

-80

-60

-40

-20

D003

CHx_INP

CHx_INM

1:1

(Optional)

0.1 F

1:1

(Optional)

0.1 F

TI Device

CIN

RIN

123

ADC32RF44

www.ti.com

SBAS809A – FEBRUARY 2017 – REVISED MARCH 2017

Product Folder Links: ADC32RF44

Submit Documentation Feedback

Typical Application (continued)

10.2.1 Design Requirements

10.2.1.1 Transformer-Coupled Circuits

Typical applications involving transformer-coupled circuits are discussed in this section. To ensure good

amplitude and phase balance at the analog inputs, transformers (such as TC1-1-13 and TC1-1-43) can be used

from the dc to 1000-MHz range and from the 1000-MHz to 4-GHz range of input frequencies, respectively. When

designing the driving circuits, the ADC input impedance (or SDD11) must be considered.

By using the simple drive circuit of Figure 240, uniform performance can be obtained over a wide frequency

range. The buffers present at the analog inputs of the device help isolate the external drive source from the

switching currents of the sampling circuit.

Figure 240. Input Drive Circuit

10.2.2 Detailed Design Procedure

For optimum performance, the analog inputs must be driven differentially. This architecture improves common-

mode noise immunity and even-order harmonic rejection. A small resistor (5 Ω to 10 Ω) in series with each input

pin is recommended to damp out ringing caused by package parasitics, as shown in Figure 240.

10.2.3 Application Curves

Figure 241 and Figure 242 show the typical performance at 100 MHz and 1850 MHz, respectively.

SNR = 62.7 dBFS, SINAD = 62 dBFS,

HD2 = –68 dBc, HD3 = –83 dBc, SFDR = 68 dBc,

THD = 68 dBc, IL spur = 83 dBc,

SFDR (non HD2, HD3) = 74 dBc

Figure 241. FFT for 100-MHz Input Frequency

SNR = 58.5 dBFS, SINAD = 58.2 dBFS,

HD2 = –76 dBc, HD3 = –71 dBc, SFDR = 71 dBc,

THD = 70 dBc, IL spur = 77 dBc,

SFDR (non HD2, HD3) = 74 dBc

Figure 242. FFT for 1850-MHz Input Frequency

ADC32RF44IRMPR Datasheet(PDF) 123 Page - Texas Instruments

ADC32RF44IRMPR Datasheet(HTML) 123 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL