參數(shù)資料
型號: PT4822
廠商: Texas Instruments, Inc.
英文描述: "3.3V/1.8V/1.5V 12A
中文描述: 3.3V/1.8V/1.5V 12A 輸出 48V 輸入的隔離 DC/DC 轉(zhuǎn)換器
文件頁數(shù): 29/32頁
文件大?。?/td> 764K
代理商: PT4822
For technical support and more information, see inside back cover or visit www.ti.com
Application Notes
29
Adjusting the Output Voltages of the PT4820
Triple-Output DC/DC Converters
The output voltages of the PT4820 series of triple-output
DC/DC converters, Vo
1
, Vo
2
and Vo
3
are independently
adjustable. The adjustment method uses a single external
resistor,
1
which may be used to adjust a selected output
by up to a nominal ±10% from the factory preset value.
The value of the resistor determines the magnitude of
adjustment, and the placement of the resistor determines
the direction of adjustment (up or down). Resistor val-
ues can be calculated using the appropriate formula (see
below) and the constants provided in Table 3-2. Alter-
natively the value may be selected directly from Table
3-3. The placement of each resistor is detailed as fol-
lows.
Adjust Up:
To increase a specific output, add a resistor R
1
between the appropriate Vo
x
Adj (Vo
1
Adj, Vo
2
Adj, or
Vo
3
Adj) and the output common (COM). See Fig-
ure 3-1(a) and Table 3-1 for the resistor placement and
pin connections.
Figure 3-1b
PT4820 Series
Calculation of Adjust Values
The adjust resistor values may be calculated. Use the
applicable formula and select the appropriate constants
from Table 2 for the output and model being adjusted.
R
1
[Adjust Up]
3
=
R
o
· V
r
V
a
– V
o
– R
s
k
(R
2
) [Adjust Down]
3
=
R
o
(V
a
– V
r
) – R
s
V
o
– V
a
k
Where: V
o
= Original output voltage
= Adjusted output voltage
= The reference voltage from Table 3-2
R
o
= The resistance value in Table 3-2
R
s
= The series resistance from Table 3-2
V
a
V
r
(R
2
)
+Vo
x
+V
x
Adj
COM
+Vo
x
(Adjusted Down)
Output
Common
PT4820
9,10,14,18
#
#
# - See Table 3-1 for pin connections,
where Vo
x
equals Vo
1
, Vo
2
, or Vo
3
Figure 3-1a
R
1
+Vo
x
+V
x
Adj
COM
+Vo
x
(Adjusted Up)
Output
Common
PT4820
9,10,14,18
#
#
# - See Table 3-1 for pin connections,
where Vo
x
equals Vo
1
, Vo
2
, or Vo
3
Adjust Down:
Add a resistor
(R
2
)
, between the appropriate
Vo
x
Adj (Vo
1
, Vo
2
, or Vo
3
) and the output being adjusted.
See Figure 3-1(b) and Table 1 for the resistor placement
and pin connections.
Table 3-1; Adjust Resistor Pin Connections
To Adjust Up
Connect R
1
from
Vo
x
Adj
To Adjust Down
Connect
(R
2
)
from
Vo
x
Adj
to
to
Vo
x
COM
Vo
1
Vo
2
Vo
3
11
15
19
10
14
18
11
15
19
12
16
20
Notes:
1. Use only a single 1% (or better) tolerance resistor in
either the R
1
or
(R
2
)
location to adjust a specific output.
Place the resistor as close to the ISR as possible.
2. Never connect capacitors to any of the ‘Vo
x
Adj’ pins. Any
capacitance added to these control pins will affect the
stability of the respective regulated output.
3. Adjustments made to any output must also comply with
the following limitations.
Vo
1
(Vo
2
+ 0.5V), and
Vo
1
(Vo
3
+ 0.5V)
相關(guān)PDF資料
PDF描述
PT4824 "3.3V/1.8V/1.2V 12A
PT4825 "3.3V/1.5V/1.2V 12A
PT4827 "3.3V/2.5V/1.8V 12A
PT4832 "5V/3.3V/2.5V 9A
PT4852 "3.3V/1.8V/1.5V 25A
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
PT4822A 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 3.3/1.8/1.5V 12A 48V Inpt Iso DC/DC Cnvtr RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT
PT4822C 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 3.3/1.8/1.5V 12A 48V Inpt Iso DC/DC Cnvtr RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT
PT4822N 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 3.3/1.8/1.5V 12A 48V Inpt Iso DC/DC Cnvtr RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT
PT4823 制造商:TI 制造商全稱:Texas Instruments 功能描述:35-W Triple Output Isolated DC/DC Converter for Logic Applications
PT4823A 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 3.3/2.5/1.2V 12A 48V Inpt Iso DC/DC Cnvtr RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關(guān)頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數(shù)量:2 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT