Electronic Components Datasheet Search
  English  ▼

Delete All
ON OFF
ALLDATASHEET.COM

X  

Preview PDF Download HTML

VCA824IDG4 Datasheet(PDF) 25 Page - Texas Instruments

Part No. VCA824IDG4
Description  Ultra-Wideband, > 40-dB Gain Adjust Range, Linear in V/V Variable Gain Amplifier
Download  41 Pages
Scroll/Zoom Zoom In 100% Zoom Out
Maker  TI1 [Texas Instruments]
Homepage  http://www.ti.com
Logo 

VCA824IDG4 Datasheet(HTML) 25 Page - Texas Instruments

Zoom Inzoom in Zoom Outzoom out
 25 / 41 page
background image
9
6
3
0
-3
-6
-9
-12
-15
-18
-21
-24
Frequency(Hz)
1M
10M
1G
100M
InitialFrequencyResponse
oftheVCA824withRCLoad
EqualizedFrequencyResponse
R
F
+V
IN
R
G+
R
G-
-VIN
FB
R
S
20W
V
IN1
VCA824
R
G
R
1
C
1
R
S
V
IN2
G=2 ´
´
R
F
R
G
1+sR C
G
1
1+sR C
1
1
VCA824
www.ti.com
SBOS394D – NOVEMBER 2007 – REVISED JANUARY 2016
9.1.2 Differential Equalizer
If the application requires frequency shaping (the transition from one gain to another), the VCA824 can be used
advantageously because its architecture allows the application to isolate the input from the gain setting elements.
Figure 70 shows an implementation of such a configuration. The transfer function is shown in Equation 5.
(5)
Figure 70. Differential Equalizer
This transfer function has one pole, P1 (located at RGC1), and one zero, Z1 (located at R1C1). When equalizing an
RC load, RL and CL, compensate the pole added by the load located at RLCL with the zero Z1. Knowing RL, CL,
and RG allows the user to select C1 as a first step and then calculate R1. Using RL = 75-Ω, CL = 100pF and
wanting the VCA824 to operate at a gain of 2 V/V, which gives RF = RG = 453-kΩ, allows the user to select
C1 = 15.5 pF to ensure a positive value for the resistor R1. With all these values known, to achieve greater than
300 MHz bandwidth, R1 can be calculated to be 20-Ω. Figure 71 shows the frequency response for both the
initial, unequalized frequency response and the resulting equalized frequency response.
Figure 71. Differential Equalization of an RC Load
9.1.3 Differential Cable Equalizer
A differential cable equalizer can easily be implemented using the VCA824. An example of a cable equalization
for 100 feet of Belden Cable 1694F is illustrated in Figure 73, with Figure 72 showing the result for this
implementation. This implementation has a maximum error of 0.2 dB from DC to 70 MHz.
Copyright © 2007–2016, Texas Instruments Incorporated
Submit Documentation Feedback
25
Product Folder Links: VCA824


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 


Datasheet Download




Link URL




Privacy Policy
ALLDATASHEET.COM
Does ALLDATASHEET help your business so far?  [ DONATE ]  

About Alldatasheet   |   Advertisement   |   Datasheet Upload   |   Contact us   |   Privacy Policy   |   Alldatasheet API   |   Link Exchange   |   Manufacturer List
All Rights Reserved© Alldatasheet.com


Mirror Sites
English : Alldatasheet.com  |   English : Alldatasheet.net  |   Chinese : Alldatasheetcn.com  |   German : Alldatasheetde.com  |   Japanese : Alldatasheet.jp
Russian : Alldatasheetru.com  |   Korean : Alldatasheet.co.kr  |   Spanish : Alldatasheet.es  |   French : Alldatasheet.fr  |   Italian : Alldatasheetit.com
Portuguese : Alldatasheetpt.com  |   Polish : Alldatasheet.pl  |   Vietnamese : Alldatasheet.vn