- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄360997 > ISO175 Single Supply, Rail-to-Rail, Low Cost Instrumentation Amplifier PDF資料下載
參數(shù)資料
| 型號： | ISO175 |
| 元件分類： | 測量放大器 |
| 英文描述： | Single Supply, Rail-to-Rail, Low Cost Instrumentation Amplifier |
| 中文描述： | 單電源，軌至軌，低成本儀表放大器 |
| 文件頁數(shù)： | 7/8頁 |
| 文件大小： | 160K |
| 代理商： | ISO175 |
7
ISO175
C
1
Ext Osc on
ISO175
(Pin 21)
C
2
10k
6
5
8
2
3
TTL
f
IN
2.5k
200
+15V
+5V
f
IN
(
)
C
1
= 140E-6
C
2
= 10 X C
1
, with a minimum 10nF
2.5k
6N136
10k
C
X
OPA602
R
X
1μF
Sq Wave In
Triangle Out
ISO175
Ext Osc
1k
the protection circuitry limits the input current to a safe
value of approximately 1.5 to 5mA. The inputs are protected
even if the power supplies are disconnected or turned off.
SYNCHRONIZED OPERATION
ISO175 can be synchronized to an external signal source.
This capability is useful in eliminating troublesome beat
frequencies in multichannel systems and in rejecting AC
signals and their harmonics. To use this feature, an external
signal must be applied to the Ext Osc pin. ISO175 can be
synchronized over the 400kHz to 700kHz range.
The ideal external clock signal for the ISO175 is a
±
4V sine
wave or
±
4V, 50% duty-cycle triangle wave. The Ext Osc
pin of the ISO175 can be driven directly with a
±
3V to
±
5V
sine or 25% to 75% duty-cycle triangle wave and the ISO
amp’s internal modulator/demodulator circuitry will syn-
chronize to the signal.
ISO175 can also be synchronized to a 400kHz to 700kHz
Square-Wave External Clock since an internal clamp and
filter provide signal conditioning. A square-wave signal of
25% to 75% duty cycle, and
±
3V to
±
20V level can be used
to directly drive the ISO175.
With the addition of the signal conditioning circuit shown in
Figure 2, any 10% to 90% duty-cycle square-wave signal
can be used to drive the ISO175 Ext Osc pin. With the values
shown, the circuit can be driven by a 4Vp-p TTL signal. For
a higher or lower voltage input, increase or decrease the 1k
resistor, R
X
, proportionally, e.g. for a
±
4V square-wave
(8Vp-p) R
X
should be increased to 2k
. The value of C
X
used in the Figure 2 circuit depends on the frequency of the
external clock signal. C
X
should be 30pF for ISO175.
generates an output signal component that varies in both
amplitude and frequency, as shown by the lower curve. The
lower horizontal scale shows the periodic variation in the
frequency of the output component. Note that at the carrier
frequency and its harmonics, both the frequency and ampli-
tude of the response go to zero. These characteristics can be
exploited in certain applications.
It should be noted that for the ISO175, the carrier frequency
is nominally 500kHz and the –3dB point of the amplifier is
60kHz. Spurious signals at the output are not significant
under these circumstances unless the input signal contains
significant components above 250kHz.
When periodic noise from external sources such as system
clocks and DC/DC converters are a problem, ISO175 can
be used to reject this noise. The amplifier can be synchro-
nized to an external frequency source, f
EXT
, placing the
amplifier response curve at one of the frequency and
amplitude nulls indicated in the “Signal Response vs Car-
rier Frequency” performance curve. Figure 3 shows cir-
cuitry with opto-isolation suitable for driving the Ext Osc
input from TTL levels.
ISOLATION MODE VOLTAGE
Isolation Mode Voltage (IMV) is the voltage appearing
between isolated grounds GND1 and GND2. The IMV can
induce errors at the output as indicated by the plots of IMV
versus Frequency. It should be noted that if the IMV fre-
quency exceeds f
C
/2, the output will display spurious out-
puts in a manner similar to that described above, and the
amplifier response will be identical to that shown in the
“Signal Response vs Carrier Frequency” performance curve.
This occurs because IMV-induced errors behave like input-
referred error signals. To predict the total IMR, divide the
isolation voltage by the IMR shown in “IMR vs Frequency”
performance curve and compute the amplifier response to
this input-referred error signal from the data given in the
“Signal Response vs Carrier Frequency” performance curve.
FIGURE 2. Square-Wave to Triangle Wave Signal Condi-
tioner for Driving ISO175 Ext Osc Pin.
CARRIER FREQUENCY CONSIDERATIONS
ISO175 amplifier transmit the signal across the ISO-barrier
by a duty-cycle modulation technique. This system works
like any linear amplifier for input signals having frequencies
below one half the carrier frequency, f
C
. For signal frequen-
cies above f
C
/2, the behavior becomes more complex. The
“Signal Response vs Carrier Frequency” performance curve
describes this behavior graphically. The upper curve illus-
trates the response for input signals varying from DC to
f
C
/2. At input frequencies at or above f
C
/2, the device
FIGURE 3. Synchronization with Isolated Drive Circuit for
Ext Osc Pin.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ISO176P | Precision, Isolated OPERATIONAL AMPLIFIER |
| ISO176 | |
| ISO212JP-15 | 30/PG/CL/BECU/LL/FLNG/THD INSERT/30AVG |
| ISO212KP | Low Cost, Two-Port Isolated, 1500Vrms ISOLATION AMPLIFIER |
| ISO212 | |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ISO175P | 制造商:BB 制造商全稱:BB 功能描述:Precision, Isolated INSTRUMENTATION AMPLIFIER |
| ISO176 | 制造商:BB 制造商全稱:BB 功能描述:Precision, Isolated OPERATIONAL AMPLIFIER |
| ISO176P | 制造商:Texas Instruments 功能描述:ISOLATION AMPLIFIER, 16 Pin, Plastic, DIP |
| ISO1H801G | 功能描述:電源開關(guān) IC - 配電 HIGH SIDE SWITCH RoHS:否 制造商:Exar 輸出端數(shù)量:1 開啟電阻（最大值）:85 mOhms 開啟時間（最大值）:400 us 關(guān)閉時間（最大值）:20 us 工作電源電壓:3.2 V to 6.5 V 電源電流（最大值）: 最大工作溫度:+ 85 C 安裝風格:SMD/SMT 封裝 / 箱體:SOT-23-5 |
| ISO1H801GAUMA1 | 制造商:Infineon Technologies AG 功能描述:Power Switch Hi Side 0.625A 36-Pin DSO 制造商:Infineon Technologies AG 功能描述:DRIVER IC - Tape and Reel 制造商:Infineon Technologies AG 功能描述:IC SWITCH HISIDE 8CH DSO-36 |
發(fā)布緊急采購，3分鐘左右您將得到回復。