参数资料
型号: MAX9934FART+T
厂商: MAXIM INTEGRATED PRODUCTS INC
元件分类: 模拟信号调理
英文描述: SPECIALTY ANALOG CIRCUIT, PBGA6
封装: 1 X 1.50 MM, 0.60 MM HEIGHT, ROHS COMPLIANT, UCSP-6
文件页数: 8/21页
文件大小: 939K
代理商: MAX9934FART+T
MAX9934
Effect of Input-Bias Currents
The MAX9934 has extremely low CMOS input-bias cur-
rents at both RS+ and RS- (0.1nA) when the input com-
mon-mode voltage is less than the supply voltage.
When the input common-mode voltage becomes higher
than the supply voltage, it draws the input stage operat-
ing current from RS-, 35A (typ). RS+ maintains its
CMOS input characteristics.
Low-input-bias currents are extremely useful in design
of input filters for current-sense amplifiers. Input differ-
ential filters are sometimes required to average out
rapidly varying load currents. An example of such load
currents are those consumed by a processor, or
switching power supply. Large bias and offset currents
can interact with resistors used in these external filters
to generate large input offset voltages and gain errors.
For more detailed information, see Application Note
AN3888:
Performance of Current-Sense Amplifiers with
Input Series Resistors.
Due to the low-input-bias currents, resistors as large as
10k
can be easily used without impact on error speci-
fications with the MAX9934. For applications where the
input common-mode voltage is below VCC, a balanced
differential filter can be used. For applications where
the input common-mode voltage extends above VCC,
use a one-sided filter with a capacitor between RS+
and RS-, and a filter resistor in series with RS+ to main-
tain the excellent performance of the MAX9934. See
Figure 7.
PCB Layout
For applications where the input common-mode voltage
extends above VCC, trace resistance between RSENSE
and RS- influences the effective VOS error due to the
voltage drop developed across the trace resistance by
the 35A input bias current at RS-.
Monitoring Very Low Currents
The accuracy of the MAX9934 leads to a wide dynamic
range. This applies to both unidirectional mode and
bidirectional mode. This is made possible in the unidi-
rectional mode because the output maintains gain
accuracy below 1mV as shown in the VOUT vs. VSENSE
(VOUT < 5mV) graph in the Typical Operating Char-
acteristics. Extending the useful output below 1mV
makes it possible for the MAX9934 to accurately moni-
tor very low currents.
Use as Precision
Instrumentation Amplifier
When the input common-mode voltage is below VCC,
the input bias current of the RS- input drops to the
10pA range, the same range as the RS+ input. This
low-input-bias current in combination with the rail-to-rail
common-mode input range, the extremely high com-
mon-mode rejection, and low VOS of the MAX9934
make it ideally suited for use as a precision instrumen-
tation amplifier. In addition, the MAX9934 is stable into
an infinite capacitive load, allowing filtering flexibility.
Figure 8 shows the MAX9934 in a multiplexed arrange-
ment of strain-gauge amplifiers.
UCSP Applications Information
For the latest application details on UCSP construction,
dimensions, tape carrier information, printed circuit
board techniques, bump-pad layout, and recommend-
ed reflow temperature profile, as well as the latest infor-
mation on reliability testing results go to the Maxim
website at www.maxim-ic.com/ucsp for the
Application Note 1891:
Understanding the Basics of the
Wafer-Level Chip-Scale Package (WL-CSP).
High-Precision, Low-Voltage, Current-Sense Amplifier
with Current Output and Chip Select for Multiplexing
16
______________________________________________________________________________________
BUCK
CONTROLLER
RS+
RS-
MAX9934
ASIC
Figure 7. One-Sided Input Filter
相关PDF资料
PDF描述
MAX9950FCCB SPECIALTY ANALOG CIRCUIT, PQFP64
MAX9966BGCCQ+D Quad, Low-Power, 500Mbps ATE Driver/Comparator
MAXQ2000-QBX Low-Power LCD Microcontroller
MAYK062DG 6.2 V, 0.2 W, SILICON, UNIDIRECTIONAL VOLTAGE REGULATOR DIODE
MAYS0750Y 0.15 W, SILICON, UNIDIRECTIONAL VOLTAGE REGULATOR DIODE
相关代理商/技术参数
参数描述
MAX9934FAUA+ 功能描述:电流灵敏放大器 Precision Current Sense Amp RoHS:否 制造商:Texas Instruments 通道数量: 共模抑制比(最小值):110 dB 输入补偿电压:80 uV 电源电压-最大:5.5 V 电源电压-最小:2.7 V 电源电流:350 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-16 封装:Reel
MAX9934FAUA+T 功能描述:电流灵敏放大器 Precision Current Sense Amp RoHS:否 制造商:Texas Instruments 通道数量: 共模抑制比(最小值):110 dB 输入补偿电压:80 uV 电源电压-最大:5.5 V 电源电压-最小:2.7 V 电源电流:350 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-16 封装:Reel
MAX9934TALT+T 功能描述:电流灵敏放大器 RoHS:否 制造商:Texas Instruments 通道数量: 共模抑制比(最小值):110 dB 输入补偿电压:80 uV 电源电压-最大:5.5 V 电源电压-最小:2.7 V 电源电流:350 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-16 封装:Reel
MAX9934TART+T 功能描述:电流灵敏放大器 Precision Current Sense Amp RoHS:否 制造商:Texas Instruments 通道数量: 共模抑制比(最小值):110 dB 输入补偿电压:80 uV 电源电压-最大:5.5 V 电源电压-最小:2.7 V 电源电流:350 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-16 封装:Reel
MAX9934TAUA+ 功能描述:电流灵敏放大器 Precision Current Sense Amp RoHS:否 制造商:Texas Instruments 通道数量: 共模抑制比(最小值):110 dB 输入补偿电压:80 uV 电源电压-最大:5.5 V 电源电压-最小:2.7 V 电源电流:350 uA 最大工作温度:+ 125 C 最小工作温度:- 40 C 安装风格:SMD/SMT 封装 / 箱体:VQFN-16 封装:Reel