參數(shù)資料
型號: PT4125
元件分類: DC/DC變換器
英文描述: 5.2Vout 20W 48V-Input Isolated DC-DC Converter
中文描述: 5.2Vout 20瓦48V的輸入隔離DC - DC轉(zhuǎn)換器
文件頁數(shù): 4/7頁
文件大?。?/td> 156K
代理商: PT4125
For technical support and more information, see inside back cover or visit www.ti.com
Application Notes
Using the Remote On/Off Function on the PT4120/
PT4140 Series of Isolated DC/DC Converters
For applications requiring output voltage on/off control,
the PT4120/4140 series of DC/DC converters incorporate
a remote on/off function. This function may be used in
applications that require battery conservation, power-up/
shutdown sequencing, and/or to co-ordinate the power-
up of the regulator for active in-rush current control. (See
the related application note, AN21).
This function is provided by the
Remote On/Off
control,
pin1. If pin 1 is left open-circuit, the converter provides a
regulated output whenever a valid source voltage
3
is ap-
plied between +V
in
(pin 3), and –V
in
(pin 2). Applying a
low-level ground signal
1
to pin 1 will disable the regula-
tor output
5
.
Table 1 provides details of the threshold requirements for
the
Remote On/Off
pin. Figure 1 shows how a discrete
MOSFET (Q
1
)
4
, may be referenced to the negative input
voltage rail and used with this control input.
Table 1 Inhibit Control Thresholds
Parameter
Enable (V
IH
)
Disable (V
IL
)
min
2.5V
–0.3V
max
(Open Circuit)
2, 4
0.8V
Notes:
1. The on/off control uses -V
in
(pin 2), the primary side of
the converter as its ground reference. All voltages specified
are with respect to -V
in
.
2. The on/off control internal circuitry is a high impedance
10
μ
A current source. The open-circuit voltage may be as
high as 8.3Vdc.
3. The PT4120/40 series incorporates an “Under Voltage
Lockout” (UVLO) function. This function automatically
inhibits the converter output until there is sufficient input
voltage for the converter to produce a regulated output.
Table 2 gives the applicable UVLO thresholds.
Table 2 UVLO Thresholds
Series
PT4120
PT4140
UVLO Threshold
31V Typical
15V Typical
V
in
Range
36 – 75V
18 – 40V
4. The
Remote On/Off
input of the PT4120/40 series regulators
must be controlled with an open-collector (or open-drain)
discrete transistor or MOSFET.
Do not
use a pull-up resistor.
5. When the converter output is disabled, the current drawn
from the input supply is typically reduced to 8mA (16mA
maximum).
Figure 1
Turn-On Time:
The converter typically produces a fully
regulated output voltage within 50ms after the applica-
tion of power, or the removal of the low voltage signal
6
from the
Remote On/Off
pin. The actual turn-on time
will vary with the input voltage, output load, and the
total amount of capacitance connected to the output.
Using the circuit of Figure 1, Figure 2 shows the output
voltage and input current waveforms of a PT4121 after
Q
1
is turned off. The turn off of Q
1
corresponds to the
drop in Q
1
V
gs
voltage. The waveforms were measured
with a 48Vdc input voltage, and 2.75-A resistive load.
Figure 2
+V
in
V
in
+V
o
V
o
PT4121
+Vout
Vout
+Vin
Vin
Remote
On/Off
V
o
(adj)
1
2
3
5
4
6
Q1
BSS138
Inh
Note 2
PT4120/4140 Series
Vout (2V/Div)
Iin (0.2A/Div)
Q1 Vgs (10V/Div)
HORIZ. SCALE: 5ms/Div
6. Keep the on/off transition to less than 1ms. This prevents
erratic operation of the ISR, whereby the output voltage
may drift un-regulated between 0V and the rated output
during power-up.
相關PDF資料
PDF描述
PT4126 1.5Vout 5A 48V-Input Isolated DC-DC Converter
PT4128 2.5Vout 5A 48V-Input Isolated DC-DC Converter
PT4141 3.3V. 5A 20W Isolated DC-DC Converter
PT4142 60V Single N-Channel HEXFET Power MOSFET in a TO-262 package; A IRFSL3306PBF with Standard Packaging
PT4143 100V Single N-Channel HEXFET Power MOSFET in a TO-247AC package; A IRFP150N with Standard Packaging
相關代理商/技術(shù)參數(shù)
參數(shù)描述
PT4125A 功能描述:DC/DC轉(zhuǎn)換器 5.2Vout 20W 48V-Inp Iso DC-DC Converter RoHS:否 制造商:Murata 產(chǎn)品: 輸出功率: 輸入電壓范圍:3.6 V to 5.5 V 輸入電壓(標稱): 輸出端數(shù)量:1 輸出電壓(通道 1):3.3 V 輸出電流(通道 1):600 mA 輸出電壓(通道 2): 輸出電流(通道 2): 安裝風格:SMD/SMT 封裝 / 箱體尺寸:
PT4125C 功能描述:CONVERTR DC-DC 5.2V 3.8A HRZ SMD RoHS:是 類別:電源 - 板載 >> DC DC Converters 系列:PT4120 標準包裝:10 系列:PT4570 類型:隔離 輸出數(shù):1 電壓 - 輸入(最?。?36V 電壓 - 輸入(最大):75V Voltage - Output 1:9V Voltage - Output 2:- Voltage - Output 3:- 電流 - 輸出(最大):3.3A 電源(瓦) - 制造商系列:30W 電壓 - 隔離:1.5kV(1500V) 特點:- 安裝類型:表面貼裝 封裝/外殼:19-SIP SMD 模塊 尺寸/尺寸:3.00" L x 1.19" W x 0.50" H(76.2mm x 30.2mm x 12.7mm) 包裝:托盤 工作溫度:-40°C ~ 85°C 效率:84% 電源(瓦特)- 最大:30W
PT4126 制造商:未知廠家 制造商全稱:未知廠家 功能描述:1.5Vout 5A 48V-Input Isolated DC-DC Converter
PT4126A 功能描述:DC/DC轉(zhuǎn)換器 1.5Vout 5A 48V-Input Iso DC-DC Converter RoHS:否 制造商:Murata 產(chǎn)品: 輸出功率: 輸入電壓范圍:3.6 V to 5.5 V 輸入電壓(標稱): 輸出端數(shù)量:1 輸出電壓(通道 1):3.3 V 輸出電流(通道 1):600 mA 輸出電壓(通道 2): 輸出電流(通道 2): 安裝風格:SMD/SMT 封裝 / 箱體尺寸:
PT4126C 功能描述:DC/DC轉(zhuǎn)換器 1.5Vout 5A 48V-Input Iso DC-DC Converter RoHS:否 制造商:Murata 產(chǎn)品: 輸出功率: 輸入電壓范圍:3.6 V to 5.5 V 輸入電壓(標稱): 輸出端數(shù)量:1 輸出電壓(通道 1):3.3 V 輸出電流(通道 1):600 mA 輸出電壓(通道 2): 輸出電流(通道 2): 安裝風格:SMD/SMT 封裝 / 箱體尺寸: