- 您現在的位置：買賣IC網 > PDF目錄373938 > AD8132ARZ-R7 (ANALOG DEVICES INC) Low Cost, High Speed Differential Amplifier PDF資料下載
參數資料
| 型號： | AD8132ARZ-R7 |
| 廠商： | ANALOG DEVICES INC |
| 元件分類： | 音頻／視頻放大 |
| 英文描述： | Low Cost, High Speed Differential Amplifier |
| 中文描述： | 1 CHANNEL, VIDEO AMPLIFIER, PDSO8 |
| 封裝： | ROHS COMPLIANT, MS-012AA, SOIC-8 |
| 文件頁數： | 20/32頁 |
| 文件大小： | 456K |
| 代理商： | AD8132ARZ-R7 |
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頁第16頁第17頁第18頁第19頁當前第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁
AD8132
OPERATIONAL DESCRIPTION
DEFINITION OF TERMS
Differential Voltage
The difference between two node voltages. For example, the
output differential voltage (or equivalently output differential-
mode voltage) is defined as
V
OUT, dm
= (
V
+OUT
V
OUT
)
where
V
+OUT
and
V
OUT
refer to the voltages at the +OUT and
OUT terminals with respect to a common reference.
Rev. F | Page 20 of 32
Common-Mode Voltage
The average of two node voltages. The output common-mode
voltage is defined as
V
OUT, cm
= (
V
+OUT
+
V
OUT
)/2
AD8132
C
F
+IN
–IN
R
F
C
F
R
F
R
G
R
G
+D
IN
V
OCM
–D
IN
R
L, dm
+OUT
V
O, dm
–OUT
0
Figure 64. Circuit Definitions
BASIC CIRCUIT OPERATION
One of the more useful and easy to understand ways to use
the AD8132 is to provide two equal-ratio feedback networks.
To match the effect of parasitics, comprise these networks of
two equal-value feedback resistors (R
F
) and two equal-value
gain resistors (R
G
). This circuit is shown in Figure 64.
Like a conventional op amp, the AD8132 has two differential
inputs that can be driven with both differential-mode input
voltage (V
IN, dm
) and common-mode input voltage (V
IN, cm
).
There is another input (V
OCM
) that is not present on conventional
op amps, but provides another input to consider on the AD8132.
It is totally separate from the previous inputs.
There are two complementary outputs whose response can be
defined by a differential-mode output (V
OUT, dm
) and a common-
mode output (V
OUT, cm
).
Table 10 indicates the gain from any type of input to either type
of output.
Table 10. Differential and Common-Mode Gains
Input
V
OUT, dm
V
IN, dm
R
F
/R
G
V
IN, cm
0
V
OCM
0
V
OUT, cm
0 (by design)
0 (by design)
1 (by design)
As listed in Table 10, the differential output (V
OUT, dm
) is equal to
the differential input voltage (V
IN, dm
) times RF/RG. In this case,
it does not matter if both differential inputs are driven, or only
one output is driven and the other is tied to a reference voltage,
such as ground. As seen from the two zero entries in the V
OUT, dm
column, neither of the common-mode inputs has any effect on
this gain.
The gain from V
IN, dm
to V
OUT, cm
is 0, and first-order does not
depend on the ratio matching of the feedback networks. The
common-mode feedback loop within the AD8132 provides a cor-
rective action to keep this gain term minimized. The term balance
error describes the degree that this gain term differs from 0.
The gain from V
IN, cm
to V
OUT, dm
directly depends on the matching
of the feedback networks. The analogous term for this transfer
function (used in conventional op amps) is common-mode reject-
tion ratio (CMRR). Therefore, if it has a high CMRR, the feedback
ratios must be well matched.
The gain from V
IN, cm
to V
OUT, cm
is ideally 0 and is first-order
independent of the feedback ratio matching. As in the case of
V
IN, dm
to V
OUT, cm
, the common-mode feedback loop keeps this
term minimized.
The gain from V
OCM
to V
OUT, dm
is ideally 0 when the feedback ratios
are matched only. The amount of differential output signal that is
created by varying V
OCM
is related to the degree of mismatch in the
feedback networks.
V
OCM
controls the output common-mode voltage V
OUT, cm
with
a unity-gain transfer function. With equal-ratio feedback net-
works (as previously assumed), its effect on each output is the
same, that is the gain from V
OCM
to V
OUT, dm
is 0. If not driven,
the output common-mode voltage is set with an internal voltage
divider to a level that is nominally midsupply. It is recommended
that a 0.1 μF bypass capacitor be connected to V
OCM
.
When unequal feedback ratios are used, the two gains associated
with V
OUT, dm
become nonzero. This significantly complicates
the mathematical analysis along with any intuitive understanding
of how the part operates.
相關PDF資料 |
PDF描述 |
|---|---|
| AD8132 | Low-Cost, High-Speed Differential Amplifier |
| AD8132-EVAL | Low-Cost, High-Speed Differential Amplifier |
| AD8132AR | Low-Cost, High-Speed Differential Amplifier |
| AD8132AR-REEL | Low-Cost, High-Speed Differential Amplifier |
| AD8132AR-REEL7 | Low-Cost, High-Speed Differential Amplifier |
相關代理商/技術參數 |
參數描述 |
|---|---|
| AD8132ARZ-R71 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Low Cost, High Speed Differential Amplifier |
| AD8132ARZ-REEL7 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Low Cost, High Speed Differential Amplifier |
| AD8132ARZ-RL | 功能描述:IC AMP DIFF LDIST LP 70MA 8SOIC RoHS:是 類別:集成電路 (IC) >> Linear - Amplifiers - Instrumentation 系列:- 標準包裝:50 系列:- 放大器類型:通用 電路數:2 輸出類型:滿擺幅 轉換速率:1.8 V/µs 增益帶寬積:6.5MHz -3db帶寬:4.5MHz 電流 - 輸入偏壓:5nA 電壓 - 輸入偏移:100µV 電流 - 電源:65µA 電流 - 輸出 / 通道:35mA 電壓 - 電源，單路/雙路(±):1.8 V ~ 5.25 V，±0.9 V ~ 2.625 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:10-TFSOP，10-MSOP（0.118"，3.00mm 寬） 供應商設備封裝:10-MSOP 包裝:管件 |
| AD8132ARZ-RL1 | 制造商:AD 制造商全稱:Analog Devices 功能描述:Low Cost, High Speed Differential Amplifier |
| AD8132-EVAL | 制造商:AD 制造商全稱:Analog Devices 功能描述:Low-Cost, High-Speed Differential Amplifier |
發布緊急采購，3分鐘左右您將得到回復。