- 您現在的位置：買賣IC網 > PDF目錄361092 > NCP1410 (ON SEMICONDUCTOR) 250 mA Sync-Rect PFM Step-Up DC-DC Converter with Low-Battery Detector PDF資料下載
參數資料
| 型號： | NCP1410 |
| 廠商： | ON SEMICONDUCTOR |
| 元件分類： | DC/DC變換器 |
| 英文描述： | 250 mA Sync-Rect PFM Step-Up DC-DC Converter with Low-Battery Detector |
| 中文描述： | 250毫安同步整流PFM升壓型DC - DC轉換器與低電池檢測器 |
| 文件頁數： | 10/16頁 |
| 文件大?。?/td> | 126K |
| 代理商： | NCP1410 |
NCP1410
http://onsemi.com
10
Low–Battery Detection
A comparator with 30 mV hysteresis is applied to perform
the low–battery detection function. When pin 2 (LBI) is at
a voltage, which can be defined by a resistor divider from the
battery voltage, lower than the internal reference voltage,
1.190 V the comparator output will cause a 50 Ohm low side
switch to be turned ON. It will pull down the voltage at pin
3 (LBO) which has a hundreds kilo–Ohm of pull–high
resistance. If the pin 2 voltage is higher than 1.190 V + 30
mV, the comparator output will cause the 50 Ohm low side
switch to be turned OFF, pin 3 will become high impedance,
and its voltage will be pulled high by the external resistor.
APPLICATIONS INFORMATION
Output Voltage Setting
The output voltage of the converter is determined by the
external feedback network comprised of R
FB1
and R
FB2
and
the relationship is given by:
VOUT
1.190 V
1
RFB1
RFB2
where R
F2
and R
F1
are the upper and lower feedback
resistors respectively.
Low Battery Detect Level Setting
The Low Battery Detect Voltage of the converter is
determined by the external divider network comprised of
R
LB1
and R
LB2
and the relationship is given by:
VLB
1.190 V
1
RLB1
RLB2
where R
LB1
and R
LB2
are the upper and lower divider
resistors respectively.
Inductor Selection
The NCP1410 is tested to produce optimum performance
with a 22
μ
H inductor at V
IN
= 3 V, V
OUT
= 3.3 V supplying
output current up to 250 mA. For other input/output
requirements, inductance in the range 10
μ
H to 47
μ
H can
be used according to end application specifications.
Selecting an inductor is a compromise between output
current capability and tolerable output voltage ripple. Of
course, the first thing we need to obey is to keep the peak
inductor current below its saturation limit at maximum
current and the I
LIM
of the device. In NCP1410, I
LIM
is set
at 1 A. As a rule of thumb, low inductance values supply
higher output current, but also increase the ripple at output
and reducing efficiency, on the other hand, high inductance
values can improve output ripple and efficiency, however it
also limit the output current capability at the same time. One
other parameter of the inductor is its DC resistance, this
resistance can introduce unwanted power loss and hence
reduce overall efficiency, the basic rule is selecting an
inductor with lowest DC resistance within the board space
limitation of the end application.
Capacitors Selection
In all switching mode boost converter applications, both
the input and output terminals sees pulsating voltage/current
waveforms. The currents flowing into and out of the
capacitors multiplying with the Equivalent Series
Resistance (ESR) of the capacitor producing ripple voltage
at the terminals. During the syn–rect switch off cycle, the
charges stored in the output capacitor is used to sustain the
output load current. Load current at this period and the ESR
combined and reflected as ripple at the output terminals. For
all cases, the lower the capacitor ESR, the lower the ripple
voltage at output. As a general guide line, low ESR
capacitors should be used. Ceramic capacitors have the
lowest ESR, but low ESR tantalum capacitors can also be
used as a cost effective substitute.
Optional Startup Schottky Diode for Low Battery
Voltage
In general operation, no external Schottky diode is
required, however, in case you are intended to operate the
device close to 1 V level, a Schottky diode connected
between the LX and OUT pins as shown in Figure 27 can
help during startup of the converter. The effect of the
additional Schottky was shown in Figure 8.
Figure 27. Schottky Device Between LX and
OUT Pins
NCP1410
OUT
LX
C
OUT
V
OUT
MBR0502
L
PCB Layout Recommendations
Good PCB layout plays an important role in switching
mode power conversion. Careful PCB layout can help to
minimize ground bounce, EMI noise and unwanted
feedback that can affect the performance of the converter.
Hints in the following paragraphs, can be used as guidelines
in most situations.
Grounding
Star–ground connection should be used to connect the
output power return ground, the input power return ground
and the device power ground together at one point. All high
current running paths must be thick enough for current
flowing through and producing insignificant voltage drop
along the path. Feedback signal path must be separated with
the main current path and sensing directly at the anode of the
output capacitor.
相關PDF資料 |
PDF描述 |
|---|---|
| NCP1411DMR2 | Sync-Rect PFM Step-Up DC-DC Converter with Low-Battery Detector and Ring-Killer |
| NCP1411D | Sync-Rect PFM Step-Up DC-DC Converter with Low-Battery Detector and Ring-Killer |
| NCP1411DMR2G | Sync-Rect PFM Step-Up DC-DC Converter with Low-Battery Detector and Ring-Killer |
| NCP1411 | Sync-Rect PFM Step-Up DC-DC Converter(帶有同步整流器的PFM升壓DC-DC轉換器) |
| NCP1417DMR2(中文) | 200 mA DC-DC Step-up Converter with Dual Low Battery Protection(帶雙路低電池保護的200mA步升DC-DC轉換器) |
相關代理商/技術參數 |
參數描述 |
|---|---|
| NCP1410DMR2 | 功能描述:直流/直流開關轉換器 ANA DC-DC CONVERTER RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| NCP1410DMR2G | 功能描述:直流/直流開關轉換器 ANA DC-DC CONVERTER RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| NCP1410GEVB | 功能描述:電源管理IC開發工具 NCP1410 EVAL BRD RoHS:否 制造商:Maxim Integrated 產品:Evaluation Kits 類型:Battery Management 工具用于評估:MAX17710GB 輸入電壓: 輸出電壓:1.8 V |
| NCP1411DMR2 | 功能描述:直流/直流開關轉換器 250mA Monolithic RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
| NCP1411DMR2G | 功能描述:直流/直流開關轉換器 250mA Monolithic High Frequency Boost RoHS:否 制造商:STMicroelectronics 最大輸入電壓:4.5 V 開關頻率:1.5 MHz 輸出電壓:4.6 V 輸出電流:250 mA 輸出端數量:2 最大工作溫度:+ 85 C 安裝風格:SMD/SMT |
發布緊急采購，3分鐘左右您將得到回復。