- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄362140 > ADP3031 ADP3031: 2MHz PWM Boost Switching Regulator Data Sheet (Rev. PrB. 9/02) PDF資料下載
參數(shù)資料
| 型號： | ADP3031 |
| 英文描述： | ADP3031: 2MHz PWM Boost Switching Regulator Data Sheet (Rev. PrB. 9/02) |
| 中文描述： | ADP3031：2MHz的PWM升壓開關(guān)穩(wěn)壓器數(shù)據(jù)手冊（牧師pRB的。9月2日） |
| 文件頁數(shù)： | 5/8頁 |
| 文件大小： | 181K |
| 代理商： | ADP3031 |
ADP3031
REV. PrB
–5–
PRELIMINARY TECHNICAL DATA
Table 1. Inductor Manufacturers
Max DC
Current
Max DCR
m
Height
(mm)
Part
L(μH)
Vendor
CMD4D11-2R2MC
CMD4D11-4R7MC
CDRH4D28-100
CDRH5D18-220
CR43-4R7
CR43-100
2.2
4.7
10
22
4.7
10
0.95
0.75
1.00
0.80
1.15
1.04
116
216
128
290
109
182
1.2
1.2
3.0
2.0
3.5
3.5
Sumida
847-956-0666
www.sumida.com
DS1608-472
DS1608-103
4.7
10
1.40
1.00
60
75
2.9
2.9
Coilcraft
847-639-6400 www.coilcraft.com
D52LC-4R7M
D52LC-100M
4.7
10
1.14
0.76
87
150
2.0
2.0
Toko
847-297-0070 www.tokoam.com
“grounded” it runs at its highest frequency. A resistor from
RT to ground can be used to set intermediate operating
frequencies.
Because of the large currents which flow in the main
MOSFET switch, it is provided with a separate PGND
return to the negative supply terminal, to avoid corrupting
the small signal return, GND, that can be used as a sense
line at the output load point.
APPLICATION INFORMATION
Frequency Selection
The ADP3031's frequency can be user selected to operate at either
600 KHz or 2 MHz and programmable by setting the RT pin. Tie
RT to GND for 2 MHz operation. For 600 KHz operation, float the
RT pin.
The nominal resistance at the RT pin to get a switching
frequency, f
SW
, is given by:
RT (
) = 320,000 x (2,000,000 - f
SW
)/(3.6667 x f
SW
–
2,000,000)
Output Voltage
The ADP3031 features an adjustable output voltage range of
V
to 12 V. The output voltage is fed back to the ADP3031
via resistor dividers R1 and R2 (Figure 1.). The feedback
voltage is 1.233 V, so the output voltage is set by the formula:
(1)
V
OUT
= 1.233
×
( 1+ R1/R2)
(2)
Since the feedback bias current is 100 nA maximum, R2 may
have a value up to 100 K
with minimum error due to the bias
current.
Inductor Selection
For most of the applications, the inductor used with the
ADP3031 should be in the range of 2 μH to 22 μH. Several
inductor manufacturers are listed in Table 1. When select-
ing an inductor, it is important to make sure that the
inductor used with the ADP3031 is able to handle the peak
current without saturation and that the peak current is
below the current limit of the ADP3031.
As a rule, powdered iron cores saturate softly, whereas
Ferrite cores saturate abruptly. Open drum core inductors
tend to saturate gradually, are low cost and are small in size,
making these types of inductors attractive in many applica-
tions. However, care must be exercised in their placement
because they have high magnetic fields. In applications that
are sensitive to magnetic fields, shielded geometries are
recommended.
In addition, inductor losses must be considered. Both core
and copper losses contribute to loss in converter efficiency.
To minimize core losses, look for inductors rated for
operation at high switching frequencies. To minimize
copper losses, it is best to use low dc resistance inductors.
Typically, it is best to use an inductor with a dc resistance
lower than 20 m
per μH.
The inductor value can be estimated using the following:
L = (V
OUT
- V
IN
)
×
M
SLOPE
Where M
SLOPE
= scaling factor for proper slope compen-
sation.
SLOPE
M
SW
f
1.456
=
Choose the closest standard inductor value as a starting
point.
The corresponding peak inductor current can then be
calculated:
(
)
(
)
IN
OUT
V
IN
OUT
V
V
L
OUT
I
IN
OUT
S
V
V
f
I
PEAK
L V
1
2
×
×
(3)
=
×
+
It is recommended to try several different inductor values,
sizes and types to find the best inductor for the application.
In general, large inductor values lead to lower ripple
current, less output noise, and either larger size or higher
DC resistance. Conversely, low inductor values lead to
higher ripple current, more noise, and either smaller size or
lower DC resistance. The final inductor selection should be
based on the best trade-off of size, cost, and performance.
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| ADP3050AR-3.3 | Analog IC |
| ADP3089 | ADP3089: 1MHz. 1A Buck Regulator Preliminary Data Sheet (Rev. PrE. 9/02) |
| ADP3156JR-1.5 | Current-Mode SMPS Controller |
| ADP3156JR-1.8 | Current-Mode SMPS Controller |
| ADP3156JR-2.5 | Current-Mode SMPS Controller |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| ADP3031ARM | 制造商:AD 制造商全稱:Analog Devices 功能描述:2 MHz PWM Boost Switching Regulator |
| ADP3040ARM-REEL7 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Analog Devices 功能描述: |
| ADP3040ARMZ-REEL7 | 制造商:Rochester Electronics LLC 功能描述: 制造商:Analog Devices 功能描述: |
| ADP3041 | 制造商:AD 制造商全稱:Analog Devices 功能描述:TFT LCD Panel Power Module |
| ADP3041ARU | 制造商:AD 制造商全稱:Analog Devices 功能描述:TFT LCD Panel Power Module |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。