- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄367055 > HCPL-786J-XXXE Optically Isolated Sigma-Delta Modulator PDF資料下載
參數(shù)資料
| 型號： | HCPL-786J-XXXE |
| 英文描述： | Optically Isolated Sigma-Delta Modulator |
| 中文描述： | 光隔離Σ-Δ調制器 |
| 文件頁數(shù)： | 17/18頁 |
| 文件大小： | 560K |
| 代理商： | HCPL-786J-XXXE |
17
Shunt Connections
The recommended method for
connecting the isolated
modulator to the shunt resistor
is shown in Figure 17. V
IN+
(pin 2 of the HPCL-7860/
HCPL-786J) is connected to
the positive terminal of the
shunt resistor, while V
IN-
(pin
3) is shorted to GND1 with the
power-supply return path
functioning as the sense line
to the negative terminal of the
current shunt. This allows a
single pair of wires or PC
board traces to connect the
isolated modulator circuit to
the shunt resistor. By
referencing the input circuit to
the negative side of the sense
resistor, any load current
induced noise transients on
the shunt are seen as a
common-mode signal and will
not interfere with the current-
sense signal. This is important
because the large load currents
flowing through the motor
drive, along with the parasitic
inductances inherent in the
wiring of the circuit, can
generate both noise spikes and
offsets that are relatively large
compared to the small voltages
that are being measured across
the current shunt.
If the same power supply is
used both for the gate drive
circuit and for the current
sensing circuit, it is very
important that the connection
from GND1 of the isolated
modulator to the sense resistor
be the only return path for
supply current to the gate
drive power supply in order to
eliminate potential ground loop
problems. The only direct
connection between the
isolated modulator circuit and
the gate drive circuit should
be the positive power supply
line.
In some applications, however,
supply currents flowing
through the power-supply
return path may cause offset
or noise problems. In this
case, better performance may
be obtained by connecting V
IN+
and V
IN-
directly across the
shunt resistor with two
conductors, and connecting
GND1 to the shunt resistor
with a third conductor for the
power-supply return path, as
shown in Figure 19. When
connected this way, both input
pins should be bypassed. To
minimize electromagnetic
interference of the sense
signal, all of the conductors
(whether two or three are
used) connecting the isolated
modulator to the sense resistor
should be either twisted pair
wire or closely spaced traces
on a PC board.
The 39
resistor in series
with the input lead (R2) forms
a lowpass anti-aliasing filter
with the 0.01
μ
F input bypass
capacitor (C2) with a 400 kHz
bandwidth. The resistor
performs another important
function as well; it dampens
any ringing which might be
present in the circuit formed
by the shunt, the input bypass
capacitor, and the inductance
of wires or traces connecting
the two. Undamped ringing of
the input circuit near the
input sampling frequency can
alias into the baseband
producing what might appear
to be noise at the output of
the device.
Figure 19. Schematic for Three Conductor Shunt Connection.
+
-
MOTOR
HV-
HV+
R
SENSE
FLOATING
POSITIVE
SUPPLY
GATE DRIVE
CIRCUIT
V
DD1
V
IN+
V
IN-
GND1
V
DD2
MCLK
MDAT
GND2
HCPL-7860/
HCPL-786J
C1
0.1 μF
C2a
0.01 μF
R2a 39
R1
D1
5.1 V
C2b
0.01 μF
R2b 39
相關PDF資料 |
PDF描述 |
|---|---|
| HCR4148M | surface mount switching diode |
| HCS12COREUG | Device User Guide V01.18 |
| HCS12H | 16-bit Microcontroller |
| HCS2-110-F | RF Coaxial Switches (DC to 15 GHz) |
| HCS2-111-F | RF Coaxial Switches (DC to 15 GHz) |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| HCPL-788J | 功能描述:隔離放大器 4.5 - 5.5 SV RoHS:否 制造商:Texas Instruments 輸入補償電壓:1.5 mV 共模抑制比（最小值）:95 dB 帶寬:60 KHz 工作電源電壓:3.3 V 電源電流:8 mA 工作溫度范圍:- 40 C to + 105 C 安裝風格:SMD/SMT 封裝 / 箱體:SOP-8 封裝:Tube |
| HCPL-788J#500 | 功能描述:隔離放大器 4.5 - 5.5 SV RoHS:否 制造商:Texas Instruments 輸入補償電壓:1.5 mV 共模抑制比（最小值）:95 dB 帶寬:60 KHz 工作電源電壓:3.3 V 電源電流:8 mA 工作溫度范圍:- 40 C to + 105 C 安裝風格:SMD/SMT 封裝 / 箱體:SOP-8 封裝:Tube |
| HCPL-788J/EVAL | 制造商:Avago Technologies 功能描述: |
| HCPL-788J-000E | 功能描述:隔離放大器 4.5 - 5.5 SV RoHS:否 制造商:Texas Instruments 輸入補償電壓:1.5 mV 共模抑制比（最小值）:95 dB 帶寬:60 KHz 工作電源電壓:3.3 V 電源電流:8 mA 工作溫度范圍:- 40 C to + 105 C 安裝風格:SMD/SMT 封裝 / 箱體:SOP-8 封裝:Tube |
| HCPL-788J-500E | 功能描述:隔離放大器 4.5 - 5.5 SV RoHS:否 制造商:Texas Instruments 輸入補償電壓:1.5 mV 共模抑制比（最小值）:95 dB 帶寬:60 KHz 工作電源電壓:3.3 V 電源電流:8 mA 工作溫度范圍:- 40 C to + 105 C 安裝風格:SMD/SMT 封裝 / 箱體:SOP-8 封裝:Tube |
發(fā)布緊急采購，3分鐘左右您將得到回復。