поискавой системы для электроныых деталей
  Russian  ▼
ALLDATASHEETRU.COM

X  

AD8345ARE датащи(PDF) 8 Page - Analog Devices

номер детали AD8345ARE
подробное описание детали  250 MHz.1000 MHz Quadrature Modulator
Download  16 Pages
Scroll/Zoom Zoom In 100%  Zoom Out
производитель  AD [Analog Devices]
домашняя страница  http://www.analog.com
Logo AD - Analog Devices

AD8345ARE датащи(HTML) 8 Page - Analog Devices

Back Button AD8345ARE Datasheet HTML 4Page - Analog Devices AD8345ARE Datasheet HTML 5Page - Analog Devices AD8345ARE Datasheet HTML 6Page - Analog Devices AD8345ARE Datasheet HTML 7Page - Analog Devices AD8345ARE Datasheet HTML 8Page - Analog Devices AD8345ARE Datasheet HTML 9Page - Analog Devices AD8345ARE Datasheet HTML 10Page - Analog Devices AD8345ARE Datasheet HTML 11Page - Analog Devices AD8345ARE Datasheet HTML 12Page - Analog Devices Next Button
Zoom Inzoom in Zoom Outzoom out
 8 / 16 page
background image
REV. 0
AD8345
–8–
CIRCUIT DESCRIPTION
Overview
The AD8345 can be divided into the following sections: Local
Oscillator (LO) Interface, Mixer, Differential Voltage-to-Cur-
rent (V-to-I) Converter, Differential-to-Single-Ended (D-to-S)
Converter, and Bias. A block diagram of the part is shown in
Figure 2.
OUT
LOIP
LOIN
IBBP
IBBN
QBBP
QBBN
PHASE
SPLITTER
Figure 2. AD8345 Block Diagram
The LO Interface generates two LO signals at 90 degrees of
phase difference with each other, to drive two mixers in quadra-
ture. Baseband signals are converted into current form in the
Differential V-to-I Converters, feeding into the two mixers. The
outputs of the mixers are combined to feed the Differential-to-
Single-Ended Converter, which provides a 50
Ω output interface.
Bias currents to each section are controlled by the Enable
(ENBL) signal. Detailed description of each section follows.
LO Interface
The LO Interface consists of interleaved stages of polyphase
phase-splitters and buffer amplifiers. The polyphase phase-splitter
contains resistors and capacitors connected in a circular manner
to split the LO signal into I and Q paths in precise quadra-
ture with each other. The signal on each path goes through a
buffer amplifier to make up for the loss and high frequency
roll-off. The two signals then go through another polyphase
network to enhance the quadrature accuracy. The broad oper-
ating frequency range (250 MHz to 1000 MHz) is achieved
by staggering the RC time constants of each stage of the phase-
splitters. The outputs of the second phase-splitter are fed into
the driver amplifiers for the mixers’ LO inputs.
Differential V-to-I Converter
In this circuit, each baseband input pin is connected to an op amp
driving a transistor connected as an emitter follower. A resistor
between the two emitters maintains a varying current propor-
tional to the differential input voltage through the transistor. These
currents are fed to the two mixers in differential form.
Mixers
There are two double-balanced mixers, one for the In-phase
Channel (I-Channel) and one for the Quadrature Channel (Q-
Channel). Each mixer uses the Gilbert-cell design with four
cross-connected transistors. The bases of the transistors are
driven by the LO signal of the corresponding channel. The
output currents from the two mixers are summed together in
two load resistors. The signal developed across the load resistors
is sent to the D-to-S stage.
Differential to Single-Ended Converter
The differential-to-single-ended converter consists of two emit-
ter followers driving a totem-pole output stage whose output
impedance is established by the emitter resistors in the output
transistors. The output of this stage is connected to the output
(VOUT) pin.
Bias
A bandgap reference circuit based on the
∆-VBE principle gen-
erates the Proportional-To-Absolute-Temperature (PTAT) as
well as temperature-stable currents used by the different sec-
tions as references. When the bandgap reference is disabled by
pulling down the voltage at the ENBL pin, all other sections are
shut off accordingly.
LO LEVEL – dBm
–150
–10
–152
–160
–151
–153
–154
–155
VS = 5V
–156
–157
–158
–159
–9
–8
–7
–6
–5
–4
–3
–2
–1
012
TPC 19. Noise Floor vs. LO Input Power. (TA = 25
°C, FLO =
800 MHz, VS = 5 V, All I and Q Inputs are DC-Biased to
0.7 V) Noise Measured at 20 MHz Offset from Carrier
LO LEVEL – dBm
–36
–10
VS = 5.5V
–40
–50
–38
–42
–44
–46
–48
–9
–8
–7
–6
–5
–4
–3
–2
–1
012
TPC 20. LO Feedthrough vs. LO Input Power. (TA = 25
°C,
LO = 800 MHz, VS = 5.5 V)


Аналогичный номер детали - AD8345ARE

производительномер деталидатащиподробное описание детали
logo
Analog Devices
AD8345ARE AD-AD8345ARE Datasheet
362Kb / 20P
   140 MHz to 1000 MHz Quadrature Modulator
REV. B
AD8345ARE-REEL7 AD-AD8345ARE-REEL7 Datasheet
362Kb / 20P
   140 MHz to 1000 MHz Quadrature Modulator
REV. B
AD8345AREZ AD-AD8345AREZ Datasheet
362Kb / 20P
   140 MHz to 1000 MHz Quadrature Modulator
REV. B
AD8345AREZ-RL7 AD-AD8345AREZ-RL7 Datasheet
362Kb / 20P
   140 MHz to 1000 MHz Quadrature Modulator
REV. B
More results

Аналогичное описание - AD8345ARE

производительномер деталидатащиподробное описание детали
logo
List of Unclassifed Man...
STQ-1016 ETC-STQ-1016 Datasheet
146Kb / 6P
   250 - 1000 MHz Direct Quadrature Modulator
logo
SIRENZA MICRODEVICES
STQ-1016 SIRENZA-STQ-1016 Datasheet
138Kb / 6P
   250 - 1000 MHz Direct Quadrature Modulator
logo
ATMEL Corporation
U2790B ATMEL-U2790B Datasheet
228Kb / 15P
   1000-MHz QUADRATURE MODULATOR
logo
TEMIC Semiconductors
U2797B TEMIC-U2797B Datasheet
255Kb / 13P
   1000-MHz Quadrature Modulator
logo
ATMEL Corporation
U2790B ATMEL-U2790B_06 Datasheet
322Kb / 16P
   1000-MHz Quadrature Modulator
logo
Analog Devices
AD8345 AD-AD8345_15 Datasheet
1,020Kb / 20P
   140 MHz to 1000 MHz Quadrature Modulator
REV. B
ADL5370 AD-ADL5370 Datasheet
2Mb / 20P
   300 MHz to 1000 MHz Quadrature Modulator
REV. 0
AD8345AREZ AD-AD8345AREZ Datasheet
362Kb / 20P
   140 MHz to 1000 MHz Quadrature Modulator
REV. B
logo
ATMEL Corporation
U2793B ATMEL-U2793B_06 Datasheet
329Kb / 13P
   300-MHz Quadrature Modulator
U2793B ATMEL-U2793B Datasheet
255Kb / 12P
   300 MHZ QUADRATURE MODULATOR
More results


Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16


датащи скачать

Go To PDF Page


ссылки URL




Конфиденциальность
ALLDATASHEETRU.COM
Вашему бизинису помогли Аллдатащит?  [ DONATE ] 

Что такое Аллдатащит   |   реклама   |   контакт   |   Конфиденциальность   |   обмен ссыками   |   поиск по производителю
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
Indian : Alldatasheet.in  |   Mexican : Alldatasheet.com.mx  |   British : Alldatasheet.co.uk  |   New Zealand : Alldatasheet.co.nz
Family Site : ic2ic.com  |   icmetro.com