- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄383234 > L5980 (意法半導(dǎo)體) 0.7A step-down switching regulator PDF資料下載
參數(shù)資料
| 型號： | L5980 |
| 廠商： | 意法半導(dǎo)體 |
| 英文描述： | 0.7A step-down switching regulator |
| 中文描述： | 0.7A的降壓開關(guān)穩(wěn)壓器 |
| 文件頁數(shù)： | 15/37頁 |
| 文件大?。?/td> | 959K |
| 代理商： | L5980 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁當(dāng)前第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁
Application informations
L5980
15/37
5.2
Inductor selection
The inductance value fixes the current ripple flowing through the output capacitor. So the
minimum inductance value in order to have the expected current ripple has to be selected.
The rule to fix the current ripple value is to have a ripple at 20%-40% of the output current.
The inductance value can be calculated by the following equation:
Equation 6
Where T
ON
and T
OFF
are the on and off time of the internal power switch. The maximum
current ripple, at fixed Vout, is obtained at maximum T
OFF
that is at minimum duty cycle (see
previous section to calculate minimum duty). So fixing
I
L
=20% to 40% of the maximum
output current, the minimum inductance value can be calculated:
Equation 7
where F
SW
is the switching frequency, 1/(T
ON
+ T
OFF
).
For example for V
OUT
=3.3V, V
IN
=12V, I
O
=0.7A and F
SW
=250kHz the minimum inductance
value to have
I
L
=30% of I
O
is about 45
μ
H.
The peak current through the inductor is given by:
Equation 8
So if the inductor value decreases, the peak current (that has to be lower than the current
limit of the device) increases. The higher is the inductor value, the higher is the average
output current that can be delivered, without reaching the current limit.
In the table below some inductor part numbers are listed.
Table 6.
Inductors
Manufacturer
Series
Inductor value (
μ
H)
Saturation current (A)
Wurth
TPC XL
10 to 33
1.3 to 2.5
PD3 L
33 to 68
1.35 to 1.8
Coilcraft
MSS1038
39 to 68
1.62 to 2.04
LPS6235
12 to 33
1.4 to 2.2
I
L
V
-----------–
T
ON
V
L
V
L
--------------
T
OFF
=
=
L
MIN
V
I
MAX
F
---------------+
1
---–
D
F
SW
=
I
L PK
I
O
I
L
2
-------
+
=
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| L5980TR | 0.7A step-down switching regulator |
| L5985 | 2A step-down switching regulator |
| L5985TR | 2A step-down switching regulator |
| L5991 | PRIMARY CONTROLLER WITH STANDBY |
| L5991A | PRIMARY CONTROLLER WITH STANDBY |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| L5980_08 | 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:0.7 A step-down switching regulator |
| L5980TR | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 700mA 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 |
| L5980TR-CUT TAPE | 制造商:ST 功能描述:L5980 Series 15 V 250 kHz 0.7 A Step Down Switching Regulator - VFQFPN-8 |
| L5981 | 功能描述:直流/直流開關(guān)調(diào)節(jié)器 1A STEP-DOWN SWITCH 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 |
| L5981_08 | 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:1 A step-down switching regulator |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。