带前½放大器和可编程输入
电阻(R
IN
)的超½噪声VGA
AD8331/AD8332/AD8334
产品特性
超½噪声前½放大器
电压噪声
= 0.74 nV/√Hz
电流噪声
= 2.5 pA/√Hz
3 dB带½
AD8331:120
MHz
AD8332、AD8334:100
MHz
½功耗
AD8331:每通道125 mW
AD8332、AD8334:每通道145 mW
可编程后½放大器提供½增益范围
LO增益模式:−4.5 dB至+43.5 dB
HI增益模式:7.5 dB至55.5 dB
折合到输出端的噪声较½:48
nV/√Hz(典型值)
有源输入阻抗匹配
针对10½/12½ADC优化
可选输出钳½电平
采用5
V单电源供电
AD8332和AD8334提供引脚架构芯片级封装
LNA
–
INH
19dB
48dB
ATTENUATOR
+
功½框图
L ON L OP
VIP
VIN
VCM
V
MID
3.5dB OR 15.5dB
VOH
21dB
PA
VOL
GAIN
CONTROL
INTERFACE
CLAMP
RCLMP
HIL O
LMD
VCM
BIAS
VGA BIAS AND
INTERPOLATOR
ENB
GAIN
图1. 信号路径功½框图
60
50
40
30
20
10
0
–10
100k
V
GAIN
= 1V
V
GAIN
= 0.8V
V
GAIN
= 0.6V
V
GAIN
= 0.4V
V
GAIN
= 0.2V
V
GAIN
= 0V
HI GAIN
MODE
超声和声纳时间增益控制
高性½自动增益控制(AGC)系统
I/Q信号处理
高速、双通道ADC驱动器
GAIN (dB)
应用
概述
AD8331/AD8332/AD8334分别是单通道/双通道/四通道、超
½噪声、线性dB可变增益放大器(VGA),针对超声系统进
行了优化,可以用½½噪声可变增益元件,工½频率最高
达120
MHz。
各通道内½一个超½噪声前½放大器(LNA)、一个48
dB增益
范围的X-AMP®
VGA以及一个具有可调输出限制功½的可
选增益后½放大器。LNA增益为19
dB,具有单端输入和差分
输出。LNA输入阻抗可以利用一个电阻来调节,以便与信
号源相匹配,且不½响噪声性½。
VGA的48 dB增益范围½这些器件适合各种不同的应用。带
½在整个增益范围内可保持出色的一致性。对于40
mV至1 V
范围内的控制电压,增益控制接口可提供精确的50
dB/V线
性dB调整。通过工厂调整可确保器件间及通道间具有出色
的增益匹配特性。
1M
10M
FREQUENCY (Hz)
100M
1G
图2. 频率响应与增益的关系
差分信号路径提供出色的二次和三次失真性½及½串扰。
VGA的½输出端噪声在驱动高速差分ADC时是种优势。后
½放大器的增益可通过引脚选择为3.5
dB或15.5 dB,以便优
化12½或10½½换器应用的增益范围和输出噪声。输出可
以用户选择的箝½电平为限,防止后续ADC的输入过½½。
一个外部电阻调整该箝½电平。
工½温度范围为−40°C至+85°C。AD8331提供20引脚QSOP
封装,AD8332提供28引脚TSSOP和32引脚LFCSP封装,
AD8334提供64引脚LFCSP封装。
Rev. G
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Speci cations subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2003–2010 Analog Devices, Inc. All rights reserved.
ADI中文版数据手册是英文版数据手册的译文,敬请谅解翻译中可½存在的语言组织或翻译错误,ADI不对翻译中存在的差异或由此产生的错误负责。如需确认任½词语的准确性,请参考ADI提供
的最新英文版数据手册。
03199-002
03199-001
AD8331/AD8332/AD8334
AD8331/AD8332/AD8334
目½
产品特性
......................................................................................... 1
应用..................................................................................................
1
概述..................................................................................................
1
功½框图
......................................................................................... 1
修订历史
......................................................................................... 2
技术规格
......................................................................................... 4
绝对最大额定值............................................................................
7
ESD警告..................................................................................... 7
引脚配½和功½描述
................................................................... 8
典型工½特性
.............................................................................. 12
测试电路
....................................................................................... 20
测量考虑..................................................................................
20
工½原理
....................................................................................... 24
概述
.......................................................................................... 24
½噪声放大器(LNA)
............................................................. 25
可变增益放大器.....................................................................
27
后½放大器
............................................................................. 28
应用信息
....................................................................................... 30
LNA—外部器件 ..................................................................... 30
ADC驱动 ................................................................................. 32
过½½
.......................................................................................... 32
可选输入过½½保护
............................................................... 32
布局布线、接地和旁路
....................................................... 33
多路输入匹配
......................................................................... 33
禁用LNA
.................................................................................. 33
超声TGC应用
......................................................................... 34
高密度四通道布局
................................................................ 34
AD8331评估板............................................................................. 39
概述
.......................................................................................... 39
用户提供的可选器件............................................................
39
测量设½..................................................................................
39
电路板布局
............................................................................. 39
AD8331评估板原理图 .......................................................... 40
AD8331评估板PCB各层....................................................... 42
AD8332评估板............................................................................. 43
概述
.......................................................................................... 43
用户提供的可选器件............................................................
43
测量设½..................................................................................
43
电路板布局
............................................................................. 43
评估板原理图
......................................................................... 44
AD8332评估板PCB各层....................................................... 46
AD8334评估板............................................................................. 47
概述
.......................................................................................... 47
配½输入阻抗
......................................................................... 48
测量设½..................................................................................
48
电路板布局
............................................................................. 48
评估板原理图
......................................................................... 49
AD8334评估板PCB各层....................................................... 51
外½尺寸
....................................................................................... 53
订购指南..................................................................................
55
修订历史
2010年10月—修订版F至修订版G
更改表1中的“每通道静态电流”参数
....................................... 6
更改表3中的引脚1........................................................................
8
更改表4中的引脚1和引脚28、表5中的引脚4和引脚5
........ 9
更改图6和表6
.............................................................................. 10
更改图33
....................................................................................... 16
更改图64
....................................................................................... 22
更改图70
....................................................................................... 24
更改“½噪声放大器(LNA)”部分和图74...................................
5
更改图94
....................................................................................... 38
更改“概述”部分、图95标题、表10和
“电路板布局”部分 ...................................................................... 39
更改图96
....................................................................................... 40
更改图97
....................................................................................... 41
更改图98和图103
........................................................................ 42
删除“AD8331材料清单”部分和表11;重新排序
................. 43
更改图104
..................................................................................... 43
更改图106
..................................................................................... 45
更改图107
..................................................................................... 46
更改图113
..................................................................................... 47
修改图114和“电路板布局”部分
.............................................. 48
删除“AD8332材料清单”部分和表13;重新排序
................. 48
更改图115
..................................................................................... 49
更改图116
..................................................................................... 50
更改图117至图120......................................................................
51
更改图121
..................................................................................... 52
删除“AD8334材料清单”部分和表15;重新排序
................. 54
Rev. G | Page 2 of 56
AD8331/AD8332/AD8334
2008年4月—修订版E至修订版F
R
FB
通篇更改为R
IZ
.......................................................................... 4
更改图1
........................................................................................... 1
更改表1的LNA和VGA特性、输出失调电压、条件
............ 4
更改“每通道静态电流”参数和“掉电电流”参数.....................
6
更改表2
.......................................................................................... 7
更改表3(引脚1的描述)
................................................................ 8
更改表4(引脚1和引脚28的描述)...............................................
9
更改表5(引脚4和引脚5的描述).................................................
9
更改表6(引脚2、引脚15和引脚20的描述)
........................... 10
更改表6(引脚61的描述)
............................................................ 11
更改典型工½特性部分的默认条件.......................................
12
更改图25
....................................................................................... 15
更改图39
....................................................................................... 17
更改图55至图68
.......................................................................... 20
更改工½原理的概述部分
....................................................... 24
更改“½噪声放大器”部分和图74
............................................ 25
更改“有源阻抗匹配”部分、图75和图77
............................... 26
更改图78
....................................................................................... 27
更改公式6、表7、图81和图82
................................................ 30
更改图83
....................................................................................... 31
更改图88
....................................................................................... 32
调换图89和图90
.......................................................................... 33
更改图89
....................................................................................... 33
更改“超声TGC应用”部分
......................................................... 34
纳入AD8331-EVAL数据手册修订版A
................................... 39
更改“用户提供的可选器件”部分和“测量设½”部分..........
39
更改图95
....................................................................................... 39
更改图97
....................................................................................... 41
增加图98
....................................................................................... 42
纳入AD8332-EVALZ数据手册修订版D.................................
44
纳入AD8334-EVAL数据手册修订版0
.................................... 49
更新外½尺寸
.............................................................................. 55
更改订购指南部分
..................................................................... 57
2006年4月—修订版D至修订版E
增加AD8334
.............................................................................通篇
更改图1和图2
................................................................................ 1
更改表1
........................................................................................... 4
更改表2
........................................................................................... 7
更改图7至图9和图12
................................................................. 12
更改图13、图14、图16和图18
................................................ 13
更改图23和图24
.......................................................................... 14
更改图25至图27
.......................................................................... 15
更改图31和图33至图36
............................................................. 16
更改图37至图42
.......................................................................... 17
更改图43、图44和图48
............................................................. 18
更改图49、图50和图54
............................................................. 19
插入图56和图57
.......................................................................... 20
插入图58、图59和图61
............................................................. 21
更改图60
....................................................................................... 21
插入图63和图65
.......................................................................... 22
更改图64
....................................................................................... 22
移动“测量考虑”部分..................................................................
23
插入图67和图68
.......................................................................... 23
插入图70和图71
.......................................................................... 24
更改图72
....................................................................................... 24
更改图73和“½噪声放大器”部分
............................................ 25
更改“后½放大器”部分..............................................................
28
更改图80
....................................................................................... 29
更改“LNA—外部器件”部分......................................................
30
更改“逻辑输入—ENB、MODE和HILO”部分......................
31
更改“输出去耦和过½½”部分.....................................................
32
更改“布局布线、接地和旁路”部分........................................
33
更改“超声TGC应用”部分
......................................................... 34
增加“高密度四通道布局”部分
................................................ 34
插入图94
....................................................................................... 38
更新外½尺寸
.............................................................................. 39
更改订购指南部分
..................................................................... 40
2006年3月—修订版C至修订版D
格式更新
...................................................................................通篇
修改特性和概述部分
................................................................... 1
更改表1
........................................................................................... 3
更改表2
.......................................................................................... 6
更改订购指南部分
..................................................................... 34
2003年11月—修订版B至修订版C
新增器件
...................................................................................通篇
更改插图
...................................................................................通篇
更新外½尺寸
.............................................................................. 32
2003年5月—修订版A至修订版B
编辑订购指南部分
..................................................................... 32
编辑“超声TGC应用”部分
......................................................... 25
Rev. G | Page 3 of 56
AD8331/AD8332/AD8334
技术规格
除非另有说明,T
A
= 25°C,V
S
= 5 V,R
L
= 500
,R
S
= RIN = 50
,R
IZ
= 280
,C
SH
= 22 pF,f = 10 MHz,R
CLMP
= ∞,C
L
= 1 pF,
VCM引脚悬空,−4.5 dB至+43.5 dB增益(HILO = LO),差分输出电压。
表1.
参数
½噪声放大器参数
增益
输入电压范围
输入电阻
最大值 单½
1
dB
dB
mV
Ω
Ω
Ω
Ω
kΩ
pF
Ω
MHz
V/µs
nV/√Hz
pA/√Hz
dB
dB
dBc
dBc
mA
测试条件/注释
单端输入至差分输出
输入至输出(单端)
交流耦合
R
IZ
= 280 Ω
R
IZ
= 412 Ω
R
IZ
= 562 Ω
R
IZ
= 1.13 kΩ
R
IZ
= ∞
单端,任一输出
V
OUT
= 0.2 V p-p
R
S
= 0 Ω,HI或LO增益,R
IZ
= ∞,f = 5 MHz
R
IZ
= ∞,HI或LO增益,f = 5 MHz
f = 10 MHz,LOP输出
R
S
= R
IN
= 50 Ω
R
S
= 50 Ω, R
IZ
= ∞
V
OUT
= 0.5 V p-p,单端,f = 10 MHz
最小值 典型值
19
13
±275
50
75
100
200
6
13
5
130
650
0.74
2.5
3.7
2.5
−56
−70
165
输入电容
输出阻抗
−3 dB小信号带½
压摆率
输入电压噪声
输入电流噪声
噪声系数
有源终端匹配
终端开路
LOP1或LOP2的谐波失真
HD2
HD3
输出短路电流
LNA和VGA特性
−3 dB小信号带½
AD8331
AD8332, AD8334
−3 dB大信号带½
AD8331
AD8332, AD8334
压摆率
AD8331
AD8332, AD8334
输入电压噪声
噪声系数
有源终端匹配
终端开路
折合到输出端噪声
AD8331
AD8332, AD8334
输出阻抗,后½放大器
引脚LON、引脚LOP
V
OUT
= 0.2 V p-p
120
100
V
OUT
= 2 V p-p
110
90
LO增益
HI增益
LO增益
HI增益
R
S
= 0 Ω,HI或LO增益,R
IZ
= ∞,f = 5 MHz
V
GAIN
= 1.0 V
R
S
= R
IN
= 50 Ω, f = 10 MHz,实测
R
S
= R
IN
= 200 Ω, f = 5 MHz,仿真
R
S
= 50 Ω, R
IZ
= ∞, f = 10 MHz,实测
R
S
= 200 Ω, R
IZ
= ∞, f = 5 MHz,仿真
V
GAIN
= 0.5 V,LO增益
V
GAIN
= 0.5 V,HI增益
V
GAIN
= 0.5 V,LO增益
V
GAIN
= 0.5 V,HI增益
DC至1 MHz
Rev. G | Page 4 of 56
MHz
MHz
MHz
MHz
V/µs
V/µs
V/µs
V/µs
nV/√Hz
dB
dB
dB
dB
nV/√Hz
nV/√Hz
nV/√Hz
nV/√Hz
Ω
300
1200
275
1100
0.82
4.15
2.0
2.5
1.0
48
178
40
150
1
AD8331/AD8332/AD8334
参数
输出信号范围,后½放大器
差分
输出失调电压
AD8331
AD8332, AD8334
输出短路电流
谐波失真
AD8331
HD2
HD3
HD2
HD3
AD8332, AD8334
HD2
HD3
HD2
HD3
输入1
dB压缩点
双音交调失真(IMD3)
AD8331
AD8332, AD8334
输出三阶交调截点
AD8331
AD8332, AD8334
通道间串扰(AD8332、AD8334)
过½½恢复
群延迟偏差
精度
绝对增益误差
2
测试条件/注释
R
L
≥ 500 Ω,无箝½,任一引脚
最小值 典型值
最大值
V
CM
± 1.125
4.5
−50
−125
−20
−125
±5
−25
±5
–25
45
+50
+100
+20
+100
单½
1
V
V p-p
mV
mV
mV
mV
mA
差分,V
GAIN
= 0.5 V
共模
差分,0.05
V ≤ V
GAIN
≤ 1.0 V
共模
V
GAIN
= 0.5 V,V
OUT
= 1 V p-p,HI增益
f = 1 MHz
f = 10 MHz
−88
−85
−68
−65
−82
−85
−62
−66
1
dBc
dBc
dBc
dBc
dBc
dBc
dBc
dBc
dBm
f = 1 MHz
f = 10 MHz
V
GAIN
= 0.25 V,V
OUT
= 1 V p-p,f = 1 MHz
至10
MHz
V
GAIN
= 0.72 V, V
OUT
= 1 V p-p, f = 1 MHz
V
GAIN
= 0.5 V, V
OUT
= 1 V p-p, f = 10 MHz
V
GAIN
= 0.72 V, V
OUT
= 1 V p-p, f = 1 MHz
V
GAIN
= 0.5 V, V
OUT
= 1 V p-p, f = 10 MHz
V
GAIN
= 0.5 V, V
OUT
= 1 V p-p, f = 1 MHz
V
GAIN
= 0.5 V, V
OUT
= 1 V p-p, f = 10 MHz
V
GAIN
= 0.5 V, V
OUT
= 1 V p-p, f = 1 MHz
V
GAIN
= 0.5 V,
V
OUT
= 1 V p-p, f = 10 MHz
V
GAIN
= 0.5 V, V
OUT
= 1 V p-p, f = 1 MHz
V
GAIN
= 1.0 V, V
IN
= 50 mV p-p/1 V p-p,
f = 10 MHz
5 MHz < f < 50 MHz,全部增益范围
0.05 V < V
GAIN
< 0.10 V
0.10 V < V
GAIN
< 0.95 V
0.95 V < V
GAIN
< 1.0 V
0.1 V < V
GAIN
< 0.95 V
0.1 V < V
GAIN
< 0.95 V
0.10 V < V
GAIN
< 0.95 V
LO增益
HI增益
−1
−1
−2
−80
−72
−78
−74
38
33
35
32
−98
5
±2
+0.5
±0.3
−1
±0.2
±0.1
+2
+1
+1
dBc
dBc
dBc
dBc
dBm
dBm
dBm
dBm
dB
ns
ns
dB
dB
dB
dB
dB
dB/V
dB
dB
V
MΩ
ns
Ω
mV
V
增益法则一致性
3
通道间增益匹配
增益控制接口(引脚GAIN)
增益比例系数
增益范围
输入电压(V
GAIN
)范围
输入阻抗
响应时间
共模接口(PIN
VCMx)
输入电阻
4
输出CM失调电压
电压范围
48.5
48 dB增益变化至90%满量程
电流限值为±1
mA
V
CM
= 2.5 V
V
OUT
= 2.0 V p-p
50
51.5
−4.5至+43.5
7.5至55.5
0至1.0
10
500
30
−25
1.5至3.5
−125
+100
Rev. G | Page 5 of 56
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