- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384596 > LM25010MH (NATIONAL SEMICONDUCTOR CORP) 42V, 1.0A Step-Down Switching Regulator PDF資料下載
參數(shù)資料
| 型號(hào)： | LM25010MH |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 42V, 1.0A Step-Down Switching Regulator |
| 中文描述： | 1.5 A SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO14 |
| 封裝： | PLASTIC, TSSOP-14 |
| 文件頁數(shù)： | 13/17頁 |
| 文件大小： | 776K |
| 代理商： | LM25010MH |
Applications Information
(Continued)
This necessary ripple voltage is created by the inductor
ripple current acting on C2’s ESR + R3. First, the minimum
ripple current, which occurs at minimum VIN, maximum in-
ductor value, and maximum frequency, is determined.
(13)
The minimum ESR for C2 is then equal to:
If the capacitor used for C2 does not have sufficient ESR, R3
is added in series as shown in the Block Diagram. The value
chosen for C2 is application dependent, and it is recom-
mended that it be no smaller than 3.3 μF. C2 affects the
ripple at V
OUT
, and transient response. Experimentation is
usually necessary to determine the optimum value for C2.
C3:
The capacitor at the VCC pin provides noise filtering and
stability, prevents false triggering of the V
UVLO at the
buck switch on/off transitions, and limits the peak voltage at
V
when a high voltage with a short rise time is initially
applied at V
. C3 should be no smaller than 0.47 μF, and
should be a good quality, low ESR, ceramic capacitor, physi-
cally close to the IC pins.
C4:
The recommended value for C4 is 0.022 μF. A high
quality ceramic capacitor with low ESR is recommended as
C4 supplies the surge current to charge the buck switch gate
at each turn-on. A low ESR also ensures a complete re-
charge during each off-time.
C5:
This capacitor suppresses transients and ringing due to
lead inductance at VIN. A low ESR, 0.1 μF ceramic chip
capacitor is recommended, located physically close to the
LM25010.
C6:
The capacitor at the SS pin determines the soft-start
time, i.e. the time for the reference voltage at the regulation
comparator, and the output voltage, to reach their final value.
The capacitor value is determined from the following:
For a 5 ms softstart time, C6 calculates to 0.022 μF.
D1:
A Schottky diode is recommended. Ultra-fast recovery
diodes are not recommended as the high speed transitions
at the SW pin may inadvertently affect the IC’s operation
through external or internal EMI. The diode should be rated
for the maximum V
(40V), the maximum load current (1A),
and the peak current which occurs when current limit and
maximum ripple current are reached simultaneously (I
in
Figure 4), previously calculated to be 1.86A. The diode’s
forward voltage drop affects efficiency due to the power
dissipated during the off-time. The average power dissipa-
tion in D1 is calculated from:
P
D1
= V
F
x I
O
x (1 - D)
where I
O
is the load current, and D is the duty cycle.
FINAL CIRCUIT
The final circuit is shown in Figure 6, and its performance is
shown in Figures 7 & 8. Current limit measured approxi-
mately 1.3A.
20172733
FIGURE 6. Example Circuit
L
www.national.com
13
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LM25010MHX | 42V, 1.0A Step-Down Switching Regulator |
| LM25010SD | 42V, 1.0A Step-Down Switching Regulator |
| LM25010SDX | 42V, 1.0A Step-Down Switching Regulator |
| LM258P | LOW POWER DUAL OPERATIONAL AMPLIFIERS |
| LM2590HVT-ADJ | SIMPLE SWITCHER Power Converter 150 kHz 1A Step-Down Voltage Regulator, with Features |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LM25010MH/NOPB | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 42V,1.0A STEP-DOWN SWITCHING REG RoHS:否 制造商:International Rectifier 最大輸入電壓:21 V 開關(guān)頻率:1.5 MHz 輸出電壓:0.5 V to 0.86 V 輸出電流:4 A 輸出端數(shù)量: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:PQFN 4 x 5 |
| LM25010MHX | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 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 |
| LM25010MHX/NOPB | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 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 |
| LM25010Q0MH | 制造商:Rochester Electronics LLC 功能描述: 制造商:Texas Instruments 功能描述: |
| LM25010Q0MH/NOPB | 功能描述:直流/直流開關(guān)轉(zhuǎn)換器 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 |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。