- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄384606 > LP5520 (National Semiconductor Corporation) RGB Backlight LED Driver PDF資料下載
參數(shù)資料
| 型號(hào)： | LP5520 |
| 廠商： | National Semiconductor Corporation |
| 元件分類： | LED驅(qū)動(dòng)器 |
| 英文描述： | RGB Backlight LED Driver |
| 中文描述： | RGB背光LED驅(qū)動(dòng)器 |
| 文件頁數(shù)： | 26/34頁 |
| 文件大?。?/td> | 790K |
| 代理商： | LP5520 |
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頁當(dāng)前第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
Recommended External Components
OUTPUT CAPACITOR: C
OUT
The output capacitor C
directly affects the magnitude of
the output ripple voltage. In general, the higher the value of
C
, the lower the output ripple magnitude. Multilayer ce-
ramic capacitors with low ESR are the best choice. Capacitor
voltage rating must be sufficient, 25V or greater is recom-
mended. Examples of suitable capacitors are: TDK
C3216X5R1E475K, Panasonic ECJ3YB1E475K and ECJ4Y-
B1E475K.
Some ceramic capacitors, especially those in small pack-
ages, exhibit a strong capacitance reduction with the in-
creased applied voltage (DC bias effect). The capacitance
value can fall below half of the nominal capacitance. Too low
output capacitance can make the boost converter unstable.
Output capacitor value reduction due to DC bias should be
less than 70% at 20V (minimum 3 μF of real capacitance re-
maining).
INPUT CAPACITOR: C
IN
The input capacitor C
directly affects the magnitude of the
input ripple voltage and to a lesser degree the V
OUT
ripple. A
higher value C
IN
will give a lower V
IN
ripple.
OUTPUT DIODE: D
OUT
A schottky diode should be used for the output diode. To
maintain high efficiency the average current rating of the
schottky diode should be greater than the peak inductor cur-
rent (1A). Schottky diodes with a low forward drop and fast
switching speeds are ideal for increasing efficiency in portable
applications. Choose a reverse breakdown voltage of the
schottky diode significantly larger (~30V) than the output volt-
age. Do not use ordinary rectifier diodes, since slow switching
speeds and long recovery times cause the efficiency and the
load regulation to suffer. A schottky diode with low parasitic
capacitance helps in reducing EMI noise. Examples of suit-
able diodes are: Central Semiconductor CMMSH1-40 and
Infineon BAS52-02V.
EMI FILTER COMPONENTS: C
SW
, R
SW
, L
SW
and C
HF
EMI filter (R
, C
and L
) on the SW pin may be needed
to slow down the fast switching edges and reduce ringing.
These components should be as near as possible to the SW
pin to ensure reliable operation. High frequency capacitor
(C
) in the boost output helps in suppressing the high fre-
quency noise from the switcher. 50V or greater voltage rating
is recommended for the capacitors. The ferrite bead DC re-
sistance should be less than 0.1
and current rating 1A or
above. The impedance at 100 MHz should be 30 – 300
.
Examples of suitable types are TDK MPZ1608S101A and
Taiyo-Yuden FBMH 1608HM600-T.
INDUCTOR: L
1
A 4.7 μH shielded inductor is suggested for LP5520 boost
converter. The inductor should have a saturation current rat-
ing higher than the peak current it will experience during
circuit operation (0.5 – 1.0A depending on the output current).
Less than 500 m
ESR is suggested for high efficiency. Open
core inductors cause flux linkage with circuit components and
interfere with the normal operation of the circuit. This should
be avoided. For high efficiency, choose an inductor with a high
frequency core material such as ferrite to reduce the core
losses. To minimize radiated noise, use a toroid, pot core or
shielded core inductor. The inductor should be connected to
the SW pin as close to the IC as possible. Examples of suit-
able inductors are: TDK VLF3010AT-4R7MR70 and Coilcraft
LPS3010-472NL.
LIST OF RECOMMENDED EXTERNAL COMPONENTS
Symbol
C
VDDA
C
VDDD
C
VLDO
C
VDDIO
Symbol Explanation
C between V
DDA
and GND
C between V
DDD
and GND
C between V
LDO
and GND
C between VDDIO and GND
Value
100
Unit
nF
Type
Ceramic, X7R / X5R
100
nF
Ceramic, X7R, X5R
1
μF
Ceramic, X7R / X5R
100
nF
Ceramic, X7R / X5R
C
OUT
C between FB and GND
2 x 4.7
μF
Ceramic, X7R / X5R, tolerance
±10%, DC bias effect ~ –30% at
20V
Ceramic, X7R / X5R
C
IN
L
1
C between battery voltage and GND
10
μF
L between SW and V
BAT
Rectifying Diode (Vf @ maxload)
4.7
μH
Shielded, low ESR, I
SAT
0.5A
Schottky diode, reverse voltage
30V, repetitive peak current 0.5A
Ceramic, X7R / X5R, 50V
D
1
0. 3 - 0.5
V
C
SW
R
SW
C
HF
L
SW
Optional C in EMI filter
330
pF
pF
Optional R in EMI filter
3.9
±1%
Optional high frequency output C
33 - 100
Ceramic, X7R, X5R, 50V
Ferrite bead in SW pin
30 - 300
at 100 Mhz
LEDs
User Defined
www.national.com
26
L
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LP5520TL | RGB Backlight LED Driver |
| LP5520TLX | RGB Backlight LED Driver |
| LP5521 | Programmable Three Channel LED Driver |
| LP5521TM | Programmable Three Channel LED Driver |
| LP5521TMX | Programmable Three Channel LED Driver |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LP5520TL | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:RGB Backlight LED Driver |
| LP5520TL/NOPB | 功能描述:LED照明驅(qū)動(dòng)器 RoHS:否 制造商:STMicroelectronics 輸入電壓:11.5 V to 23 V 工作頻率: 最大電源電流:1.7 mA 輸出電流: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SO-16N |
| LP5520TLX | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:RGB Backlight LED Driver |
| LP5520TLX/NOPB | 功能描述:LED照明驅(qū)動(dòng)器 RoHS:否 制造商:STMicroelectronics 輸入電壓:11.5 V to 23 V 工作頻率: 最大電源電流:1.7 mA 輸出電流: 最大工作溫度: 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SO-16N |
| LP5521 | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Programmable Three Channel LED Driver |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。