- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄373936 > AD8115-EB (Analog Devices, Inc.) Low Cost 225 MHz 16 X 16 Crosspoint Switches PDF資料下載
參數(shù)資料
| 型號： | AD8115-EB |
| 廠商： | Analog Devices, Inc. |
| 英文描述： | Low Cost 225 MHz 16 X 16 Crosspoint Switches |
| 中文描述： | 低成本的225 MHz 16 × 16交叉點(diǎn)開關(guān) |
| 文件頁數(shù)： | 16/26頁 |
| 文件大小： | 363K |
| 代理商： | AD8115-EB |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁當(dāng)前第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁
AD8114/AD8115
–16–
REV. 0
APPLIED. Programming the full shift register one time to a
desired state, either by serial or parallel programming after
initial power-up, will eliminate the possibility of programming
the matrix to an unknown state.
To change an output’s programming via parallel programming,
SER
/PAR and
UPDATE
should be taken HIGH and
CE
should
be taken LOW. The CLK signal should be in the HIGH state.
The 4-bit address of the output to be programmed should be put
on A0–A3. The first four data bits (D0–D3) should contain the
information that identifies the input that gets programmed to the
output that is addressed. The fourth data bit (D4) will deter-
mine the enabled state of the output. If D4 is LOW (output
disabled) then the data on D0–D3 does not matter.
After the desired address and data signals have been established,
they can be latched into the shift register by a HIGH to LOW
transition of the CLK signal. The matrix will not be programmed,
however, until the
UPDATE
signal is taken low. It is thus pos-
sible to latch in new data for several or all of the outputs first via
successive negative transitions of CLK while
UPDATE
is held
high, and then have all the new data take effect when UPDATE
goes LOW. This is the technique that should be used when
programming the device for the first time after power-up when
using parallel programming.
POWER-ON RESET
When powering up the AD8114/AD8115 it is usually desirable
to have the outputs come up in the disabled state. The
RESET
pin, when taken LOW will cause all outputs to be in the dis-
abled state. However, the
RESET
signal DOES NOT RESET
ALL REGISTERS in the AD8114/AD8115 This is important
when operating in the parallel programming mode. Please refer
to that section for information about programming internal
registers after power-up. Serial programming will program the
entire matrix each time, so no special considerations apply.
Since the data in the shift register is random after power-up,
they should not be used to program the matrix or else the matrix
can enter unknown states. To prevent this, DO NOT APPLY
LOGIC LOW SIGNALS TO BOTH
CE
AND
UPDATE
INITIALLY AFTER POWER-UP. The shift register should
first be loaded with the desired data, and then
UPDATE
can be
taken LOW to program the device.
The
RESET
pin has a 20 k
pull-up resistor to DVDD that can
be used to create a simple power-up reset circuit. A capacitor
from
RESET
to ground will hold
RESET
LOW for some time
while the rest of the device stabilizes. The LOW condition will
cause all the outputs to be disabled. The capacitor will then
charge through the pull-up resistor to the HIGH state, thus
allowing full programming capability of the device.
GAIN SELECTION
The 16
×
16 crosspoints come in two versions, depending on the
gain of the analog circuit paths that is desired. The AD8114
device is unity gain and can be used for analog logic switching
and other applications where unity gain is desired. The AD8114
can also be used for the input and interior sections of larger
crosspoint arrays where termination of output signals is not
usually used. The AD8114 outputs have a very high impedance
when their outputs are disabled.
The AD8115 can be used for devices that will be used to drive
a terminated cable with its outputs. This device has a built-in
gain-of-two that eliminates the need for a gain-of-two buffer to
drive a video line. Its high output disabled impedance minimizes
signal degradation when paralleling additional outputs.
CREATING LARGER CROSSPOINT ARRAYS
The AD8114/AD8115 are high density building blocks for cre-
ating crosspoint arrays of dimensions larger than 16
×
16. Vari-
ous features, such as output disable, chip enable, and gain-
of-one and gain-of-two options, are useful for creating larger
they can be used with the AD8108 and AD8109, a pair (unity
gain and gain-of-two) of 8
×
8 video crosspoint switches, or the
AD8110 and AD8111, a pair (unity gain and gain-of-two)
16
×
8 video crosspoint switches.
The first consideration in constructing a larger crosspoint is to
determine the minimum number of devices are required. The
16
×
16 architecture of the AD8114/AD8115 contains 256
“points,” which is a factor of 64 greater than a 4
×
1 crosspoint
(or multiplexer). The PC board area, power consumption and
design effort savings are readily apparent when compared to
using these smaller devices.
For a nonblocking crosspoint, the number of points required is
the product of the number of inputs multiplied by the number
of outputs. Nonblocking requires that the programming of a
given input to one or more outputs does not restrict the avail-
ability of that input to be a source for any other outputs.
Some nonblocking crosspoint architectures will require more
than this minimum as calculated above. Also, there are blocking
architectures that can be constructed with fewer devices than
this minimum. These systems have connectivity available on a
statistical basis that is determined when designing the overall
system.
The basic concept in constructing larger crosspoint arrays is
to connect inputs in parallel in a horizontal direction and to
“wire-OR” the outputs together in the vertical direction. The
meaning of horizontal and vertical can best be understood by
looking at a diagram. Figure 42 illustrates this concept for a
32
×
32 crosspoint array that uses four AD8114s or AD8115s.
AD8114
OR
AD8115
AD8114
OR
AD8115
16
16
16
16
R
TERM
IN 00–15
16
16
R
TERM
IN 16–31
AD8114
OR
AD8115
AD8114
OR
AD8115
16
16
16
16
Figure 42. 32
×
32 Crosspoint Array Using Four AD8114s
or Four AD8115s
The inputs are each uniquely assigned to each of the 32 inputs
of the two devices and terminated appropriately. The outputs
are wired-ORed together in pairs. The output from only one of
a wire-ORed pair should be enabled at any given time. The
device programming software must be properly written to cause
this to happen.
Using additional crosspoint devices in the design can lower the
number of outputs that have to be wire-ORed together. Figure
43 shows a block diagram of a system using eight AD8114s and
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| AD8114 | ECONOLINE: REC2.2-S_DRW(Z)/H* - 2.2W DIP Package- 1kVDC Isolation- Regulated Output- 4.5-9V, 9-18V, 18-36V, 36-72V Wide Input Range 2 : 1- UL94V-0 Package Material- Continuous Short Circiut Protection- Cost Effective- 100% Burned In- Efficiency to 84% |
| AD8114AST | Low Cost 225 MHz 16 X 16 Crosspoint Switches |
| AD8115 | Low Cost 225 MHz 16 X 16 Crosspoint Switches |
| AD8115* | No RSENSE Current Mode Synchronous Step-Down Switching Regulator; Package: SO; No of Pins: 16; Temperature Range: 0°C to +70°C |
| AD8116 | Buffered Video Crosspoint Switch(200MHz,視頻正交開關(guān)) |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| AD8115-EVAL | 制造商:Analog Devices 功能描述:EVAL BD LOW COST 225 MHZ 16 16 CROSSPOINT SWITES - Bulk |
| AD8116 | 制造商:AD 制造商全稱:Analog Devices 功能描述:200 MHz, 16 x 16 Buffered Video Crosspoint Switch |
| AD8116-EB | 制造商:Analog Devices 功能描述:AD8116 EVALUATION BOARD - Bulk |
| AD8116JST | 制造商:Analog Devices 功能描述:Analog Video Crosspoint 200MHz 16 x 16 128-Pin LQFP 制造商:Rochester Electronics LLC 功能描述:TQFP 16X16 VIDEO CROSSPOINT SWITCH - Bulk 制造商:Analog Devices 功能描述:SWITCH CROSSPOINT 16X16 SMD 8116 |
| AD8116JSTZ | 功能描述:IC VIDEO CROSSPOINT SWIT 128LQFP RoHS:是 類別:集成電路 (IC) >> 接口 - 模擬開關(guān)，多路復(fù)用器，多路分解器 系列:- 其它有關(guān)文件:STG4159 View All Specifications 標(biāo)準(zhǔn)包裝:5,000 系列:- 功能:開關(guān) 電路:1 x SPDT 導(dǎo)通狀態(tài)電阻:300 毫歐 電壓電源:雙電源 電壓 - 電源，單路/雙路(±):±1.65 V ~ 4.8 V 電流 - 電源:50nA 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:7-WFBGA，F(xiàn)CBGA 供應(yīng)商設(shè)備封裝:7-覆晶 包裝:帶卷 (TR) |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。