參數(shù)資料
型號: MAX4378TASD+
廠商: Maxim Integrated Products
文件頁數(shù): 9/11頁
文件大小: 0K
描述: IC AMP CURRENT QUAD 14-SOIC
其它有關(guān)文件: Automotive Product Guide
產(chǎn)品培訓(xùn)模塊: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
標(biāo)準(zhǔn)包裝: 50
放大器類型: 電流檢測
電路數(shù): 4
轉(zhuǎn)換速率: 10 V/µs
-3db帶寬: 2MHz
電流 - 輸入偏壓: 800µA
電流 - 電源: 1mA
電壓 - 電源,單路/雙路(±): 3 V ~ 28 V
工作溫度: -40°C ~ 125°C
安裝類型: 表面貼裝
封裝/外殼: 14-SOIC(0.154",3.90mm 寬)
供應(yīng)商設(shè)備封裝: 14-SOIC
包裝: 管件
MAX4376/MAX4377/MAX4378
Single/Dual/Quad, High-Side Current-Sense
Amplifiers with Internal Gain
7
Maxim Integrated
Detailed Description
The MAX4376/MAX4377/MAX4378 high-side current-
sense amplifiers feature a 0 to +28V input common-mode
range that is independent of supply voltage. This feature
allows the monitoring of current out of a battery in deep
discharge and also enables high-side current sensing at
voltages greater than the supply voltage (VCC).
The MAX4376/MAX4377/MAX4378 operate as follows:
current from the source flows through RSENSE to the
load (Figure 1). Since the internal sense amplifier’s
inverting input has high impedance, negligible current
flows through RG2 (neglecting the input bias current).
Therefore, the sense amplifier’s inverting-input voltage
equals VSOURCE - (ILOAD)(RSENSE).
The amplifier’s open-loop gain forces its noninverting
input to the same voltage as the inverting input.
Therefore, the drop across RG1 equals (ILOAD)
(RSENSE). Since IRG1 flows through RG1, IRG1 =
(ILOAD)(RSENSE)/RG1. The internal current mirror multi-
plies IRG1 by a current gain factor,
β, to give IRGD = β x
IRG1. Solving IRGD =
β x (ILOAD)(RSENSE)/RG1.
Therefore:
VOUT =
β x (RGD/RG1)(RSENSE x ILOAD) x amp gain
where amp gain is 2, 5, or 10.
The part’s gain equals (
β x RGD / RG1) x amp gain.
Therefore:
VOUT = (GAIN)(RSENSE)(ILOAD)
where GAIN = 20 for MAX437_T.
GAIN = 50 for MAX437_F.
GAIN = 100 for MAX437_H.
Set the full-scale output range by selecting RSENSE and
the appropriate gain version of the MAX4376/
MAX4377/MAX4378.
Applications Information
Recommended Component Values
The MAX4376/MAX4377/MAX4378 sense a wide variety
of currents with different sense resistor values. Table 1
lists common resistor values for typical operation of the
MAX4376/MAX4377/MAX4378.
Choosing RSENSE
To measure lower currents more accurately, use a high
value for RSENSE. The high value develops a higher
sense voltage that reduces offset voltage errors of the
internal op amp.
In applications monitoring very high currents, RSENSE
must be able to dissipate the I2R losses. If the resistor’s
rated power dissipation is exceeded, its value may drift
or it may fail altogether, causing a differential voltage
across the terminals in excess of the absolute maxi-
mum ratings.
If ISENSE has a large high-frequency component, mini-
mize the inductance of RSENSE. Wire-wound resistors
have the highest inductance, metal-film resistors are
somewhat better, and low-inductance metal-film resis-
tors are best suited for these applications.
Bidirectional Current-Sense Amplifier
Systems such as laptop computers and other devices
that have internal charge circuitry require a precise
bidirectional current-sense amplifier to monitor accu-
rately the battery’s current regardless of polarity. Figure
2 shows the MAX4377 used as a bidirectional current
monitor. This is useful for implementing either smart
battery packs or fuel gauges.
Current Source Circuit
Figure 3 shows a block diagram using the MAX4376
with a switching regulator to make a current source.
相關(guān)PDF資料
PDF描述
2-32994-1 CONN RING 10-12 AWG #8
0853.9561 FUSEHOLDER COVER FOR 1.6W
MAX4378TASD IC AMP QUAD GAIN +20V/V 14-SOIC
P6KE22-E3/54 TVS 600W 22V 10% UNIDIR AXIAL
5223995-9 UPM EXPANDED RECEPTACLE ASSEMB
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MAX4378TASD+ 功能描述:電流靈敏放大器 High-Side Current-Sense Amp RoHS:否 制造商:Texas Instruments 通道數(shù)量: 共模抑制比(最小值):110 dB 輸入補償電壓:80 uV 電源電壓-最大:5.5 V 電源電壓-最小:2.7 V 電源電流:350 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-16 封裝:Reel
MAX4378TASD+T 功能描述:電流靈敏放大器 High-Side Current-Sense Amp RoHS:否 制造商:Texas Instruments 通道數(shù)量: 共模抑制比(最小值):110 dB 輸入補償電壓:80 uV 電源電壓-最大:5.5 V 電源電壓-最小:2.7 V 電源電流:350 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-16 封裝:Reel
MAX4378TASD-T 功能描述:電流靈敏放大器 High-Side Current-Sense Amp RoHS:否 制造商:Texas Instruments 通道數(shù)量: 共模抑制比(最小值):110 dB 輸入補償電壓:80 uV 電源電壓-最大:5.5 V 電源電壓-最小:2.7 V 電源電流:350 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-16 封裝:Reel
MAX4378TAUD 功能描述:特殊用途放大器 RoHS:否 制造商:Texas Instruments 通道數(shù)量:Single 共模抑制比(最小值): 輸入補償電壓: 工作電源電壓:3 V to 5.5 V 電源電流:5 mA 最大功率耗散: 最大工作溫度:+ 70 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:QFN-20 封裝:Reel
MAX4378TAUD+ 功能描述:電流靈敏放大器 High-Side Current-Sense Amp RoHS:否 制造商:Texas Instruments 通道數(shù)量: 共模抑制比(最小值):110 dB 輸入補償電壓:80 uV 電源電壓-最大:5.5 V 電源電壓-最小:2.7 V 電源電流:350 uA 最大工作溫度:+ 125 C 最小工作溫度:- 40 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:VQFN-16 封裝:Reel