- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄383334 > MAX1748-MAX8726 (Maxim Integrated Products, Inc.) Triple-Output TFT-LCD DC-DC Converters PDF資料下載
參數(shù)資料
| 型號(hào)： | MAX1748-MAX8726 |
| 廠商： | Maxim Integrated Products, Inc. |
| 元件分類： | DC/DC變換器 |
| 英文描述： | Triple-Output TFT-LCD DC-DC Converters |
| 中文描述： | 三輸出的TFT - LCD的DC - DC轉(zhuǎn)換器 |
| 文件頁(yè)數(shù)： | 12/16頁(yè) |
| 文件大?。?/td> | 277K |
| 代理商： | MAX1748-MAX8726 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)當(dāng)前第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)
M
Triple-Output TFT LCD DC-DC Converter
The MAX1748
’
s fast current-limit circuitry allows the use
of soft-saturation inductors while still protecting the IC.
The inductor
’
s DC resistance significantly affects effi-
ciency. For best performance, select inductors with
resistance less than the internal N-channel FET resis-
tance. To minimize radiated noise in sensitive applica-
tions, use a shielded inductor.
The inductor should have as low a series resistance as
possible. For continuous inductor current, the power
loss in the inductor resistance, P
LR
, is approximated by:
P
LR
(I
MAIN
V
MAIN
/ V
IN
)
2
R
L
where R
L
is the inductor series resistance.
Output Capacitor
A 10μF capacitor works well in most applications. The
equivalent series resistance (ESR) of the output filter
capacitor affects efficiency and output ripple. Output
voltage ripple is largely the product of the peak induc-
tor current and the output capacitor ESR. Use low-ESR
ceramic capacitors for best performance. Low-ESR,
surface-mount tantalum capacitors with higher capacity
may be used for load transients with high peak cur-
rents. Voltage ratings and temperature characteristics
should be considered.
Input Capacitor
The input capacitor (C
IN
) in boost designs reduces the
current peaks drawn from the input supply and reduces
noise injection. The value of C
IN
is largely determined
by the source impedance of the input supply. High
source impedance requires high input capacitance,
particularly as the input voltage falls. Since step-up DC-
DC converters act as
“
constant-power
”
loads to their
input supply, input current rises as input voltage falls. A
good starting point is to use the same capacitance
value for C
IN
as for C
OUT
. Table 1 lists suggested com-
ponent suppliers.
Integrator Capacitor
The MAX1748 contains an internal current integrator
that improves the DC load regulation but increases the
peak-to-peak transient voltage (see the load-transient
waveforms in the
Typical Operating Characteristics
).
For highly accurate DC load regulation, enable the cur-
rent integrator by connecting a 470pF capacitor to
INTG. To minimize the peak-to-peak transient voltage at
the expense of DC regulation, disable the integrator by
connecting INTG to REF and adding a 100k
resistor
to GND.
Rectifier Diode
Use a Schottky diode with an average current rating
equal to or greater than the peak inductor current, and
a voltage rating at least 1.5 times the main output volt-
age (V
MAIN
).
Charge Pump
Efficiency Considerations
The efficiency characteristics of the MAX1748 regulated
charge pumps are similar to a linear regulator. They are
dominated by quiescent current at low output currents
and by the input voltage at higher output currents (see
Typical Operating Characteristics
). So the maximum
efficiency may be approximated by:
Efficiency
V
NEG
/ [V
IN
N];
for the negative charge pump
Efficiency
V
POS
/ [V
IN
(N + 1)];
for the positive charge pump
where N is the number of charge-pump stages.
Output Voltage Selection
Adjust the positive output voltage by connecting a volt-
age-divider from the output (V
POS
) to FBP to GND (see
Typical Operating Circuit
). Adjust the negative output
SUPPLIER
INDUCTORS
Coilcraft
Coiltronics
Sumida USA
Toko
CAPACITORS
AVX
Kemet
Sanyo
Taiyo Yuden
DIODES
PHONE
FAX
847-639-6400
561-241-7876
847-956-0666
847-297-0070
847-639-1469
561-241-9339
847-956-0702
847-699-1194
803-946-0690
408-986-0424
619-661-6835
408-573-4150
803-626-3123
408-986-1442
619-661-1055
408-573-4159
Central
Semiconductor
516-435-1110
516-435-1824
International
Rectifier
310-322-3331
310-322-3332
Motorola
Nihon
Zetex
602-303-5454
847-843-7500
516-543-7100
602-994-6430
847-843-2798
516-864-7630
Table 1. Component Suppliers
12
______________________________________________________________________________________
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| MAX1748EUE | Triple-Output TFT LCD DC-DC Converter |
| MAX1755AAUT-T | SOT23 Local Temperature Comparators with SMBus Serial Interface |
| MAX1755BAUT-T | SOT23 Local Temperature Comparators with SMBus Serial Interface |
| MAX1756BAUT-T | SOT23 Local Temperature Comparators with SMBus Serial Interface |
| MAX1755 | SOT23 Local Temperature Comparators with SMBus Serial Interface |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| MAX17491GTA+ | 功能描述:功率驅(qū)動(dòng)器IC Notebook MOSFET Driver RoHS:否 制造商:Micrel 產(chǎn)品:MOSFET Gate Drivers 類型:Low Cost High or Low Side MOSFET Driver 上升時(shí)間: 下降時(shí)間: 電源電壓-最大:30 V 電源電壓-最小:2.75 V 電源電流: 最大功率耗散: 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube |
| MAX17491GTA+T | 功能描述:功率驅(qū)動(dòng)器IC Notebook MOSFET Driver RoHS:否 制造商:Micrel 產(chǎn)品:MOSFET Gate Drivers 類型:Low Cost High or Low Side MOSFET Driver 上升時(shí)間: 下降時(shí)間: 電源電壓-最大:30 V 電源電壓-最小:2.75 V 電源電流: 最大功率耗散: 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:SOIC-8 封裝:Tube |
| MAX17495AATE+ | 制造商:Maxim Integrated Products 功能描述:- Rail/Tube |
| MAX17495AATE+T | 制造商:Maxim Integrated Products 功能描述:- Tape and Reel |
| MAX17496AATE+ | 制造商:Maxim Integrated Products 功能描述:- Rail/Tube |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。