DataSheet.jp


Datasheet LTC3201 PDF ( 特性, スペック, ピン接続図 )

部品番号 LTC3201
部品説明 100mA Ultralow Noise Charge Pump Led Supply
メーカ Linear Technology Corporation
ロゴ Linear Technology Corporation ロゴ 
プレビュー
Total 8 pages
		
11

No Preview Available !

LTC3201 Datasheet, LTC3201 PDF,ピン配置, 機能
www.DataSheet4U.com
FEATURES
s Input Noise Filter Minimizes Supply Noise
s Constant Frequency Operation
s 3-Bit LED Current Control
s No Inductors
s Low Shutdown Current: IIN < 1µA
s Output Current: 100mA
s VIN Range: 2.7V to 4.5V
s 1.8MHz Switching Frequency
s Soft-Start Limits Inrush Current at Turn-On
s Short-Circuit and Overtemperature Protected
s Available in 10-Pin MSOP Package
U
APPLICATIO S
s White LED Backlighting
s Programmable Boost Current Source
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTC3201
100mA Ultralow Noise
Charge Pump LED Supply
with Output Current Adjust
DESCRIPTIO
The LTC®3201 is an ultralow noise, constant frequency,
charge pump DC/DC converter specifically designed for
powering white LEDs. The part produces a low noise
boosted supply capable of supplying 100mA of output
current. LED current is regulated for accurate and stable
backlighting. A 3-bit DAC provides output current adjust
for brightness control.
Low external parts count (one small flying capacitor and
three small bypass capacitors) and small MSOP-10 pack-
age size make the LTC3201 ideally suited for space con-
strained applications. An input noise filter further reduces
input noise, thus enabling direct connection to the battery.
High switching frequency enables the use of small external
capacitors.
The LTC3201 contains overtemperature protection and
can survive an indefinite output short to GND. Internal
soft-start circuitry also prevents excessive inrush current
on start-up. A low current shutdown feature disconnects
the load from VIN and reduces quiescent current to less
than 1µA.
TYPICAL APPLICATIO
Ultralow Noise White LED Driver
with Adjustable Current Control
0.22µF
Input Current Ripple
IOUT = 100mA
IIN = 205mA
VIN = 3.6V
+
Li ION
1µF
LED
CURRENT
ADJUST
0.22µF
3
CM CP
VIN
FILTER
VOUT
LTC3201
D0-D2
GND
FB
UP TO
6-WHITE LEDs
1µF
•••
50mA/DIV
5656
56
3201 TA01a
100ns/DIV
3201 TA01b
3201f
1

1 Page



LTC3201 pdf, ピン配列
TYwwPwI.DCaAtaSLheePt4EU.RcomFOR A CE CHARACTERISTICS
LTC3201
Feedback Voltage vs Supply
Voltage
0.640 CFLY = CFILTER = O.22µF
0.635 CIN = COUT = 1µF
TA = 85°C
0.630
0.625
TA = 25°C
0.620
0.615
TA = –40°C
0.610
0.605
2.7
3.0 3.3 3.6 3.9 4.2
SUPPLY VOLTAGE (V)
4.5
3201 G01
Short-Circuit Current vs Supply
Voltage
250 CFLY = CFILTER = O.22µF
CIN = COUT = 1µF
200 TA = 25°C
150
100
50
0
2.7 3.0 3.3 3.6 3.9 4.2 4.5
SUPPLY VOLTAGE (V)
3201 G04
Output Voltage vs Load Current
4.15 CFLY = CFILTER = O.22µF
CIN = COUT = 1µF
4.10 TA = 25°C
4.05 VIN = 4.5V
4.00
3.95
3.90 VIN = 3.2V
3.85
3.80
0
VIN = 2.7V
20 40 60 80 100 120 140 160 180 200
LOAD CURRENT (mA)
3201 G02
Feedback Voltage
vs Supply Voltage
IOUT = 100mA, VOUT = 4V
0.620
0.615
CFLY = CFILTER = O.22µF
CIN = COUT = 1µF
TA = 25°C
0.610
0.605
0.600
0.595
0.590
2.7
3.0 3.3 3.6 3.9 4.2
SUPPLY VOLTAGE (V)
4.5
3201 G05
Oscillator Frequency vs Supply
Voltage
2.2
CFLY = CFILTER = O.22µF
CIN = COUT = 1µF
2.0 VOUT = 4V
TA = –40°C
TA = 25°C
1.8
1.6
TA = 85°C
1.4
1.2
2.7
3.0 3.3 3.6 3.9 4.2
SUPPLY VOLTAGE (V)
4.5
3201 G03
Feedback Voltage vs IOUT
0.64
CFLY = CFILTER = 0.22µF
0.62
CIN = COUT = 1µF
TA = 25°C
VIN = 3.6V
0.60
0.58
0.56
0.54
0.52
0.50
0 20 40 60 80 100 120 140 160 180 200 220
IOUT (mA)
3201 G06
3201f
3


3Pages


LTC3201 電子部品, 半導体
LTC3201
APPLICATIO S Iwww.DataSheet4U.com FOR ATIO
Power Efficiency
The power efficiency (η) of the LTC3201 is similar to that
of a linear regulator with an effective input voltage of twice
the actual input voltage. This occurs because the input
current for a voltage doubling charge pump is approxi-
mately twice the output current. In an ideal regulator the
power efficiency would be given by:
η = POUT = VOUT •IOUT = VOUT
PIN VIN • 2IOUT 2VIN
At moderate to high output power the switching losses
and quiescent current of LTC3201 are relatively low. Due
to the high clocking frequency, however, the current used
for charging and discharging the switches starts to reduce
efficiency. Furthermore, due to the low VF of the LEDs,
power delivered will remain low.
Short-Circuit/Thermal Protection
The LTC3201 has short-circuit current limiting as well as
overtemperature protection. During short-circuit condi-
tions, the output current is limited to typically 150mA.
On-chip thermal shutdown circuitry disables the charge
pump once the junction temperature exceeds approxi-
mately 160°C and re-enables the charge pump once the
junction temperature drops back to approximately 150°C.
The LTC3201 will cycle in and out of thermal shutdown
indefinitely without latchup or damage until the short-
circuit on VOUT is removed.
VOUT Capacitor Selection
The style and value of capacitors used with the LTC3201
determine several important parameters such as output
ripple, charge pump strength and minimum start-up time.
To reduce noise and ripple, it is recommended that low
ESR (<0.1) capacitors be used for CFILTER, CIN, COUT.
These capacitors should be ceramic.
The value of COUT controls the amount of output ripple.
Increasing the size of COUT to 10µF or greater will reduce
the output ripple at the expense of higher turn-on times
and start-up current. See the section Output Ripple. A 1µF
COUT is recommended.
6
VIN, VFILTER Capacitor Selection
The value and resonant frequency of CFILTER and CIN
greatly determine the current noise profile at VIN. CFILTER
should be a high frequency 0.22µF capacitor with a reso-
nant frequency over 30MHz. Input capacitor CIN should be
a 1µF ceramic capacitor with a resonant frequency over
1MHz. The X5R capacitor is a good choice for both. The
values of CFILTER (0.22µF) and CIN (1µF) provide optimum
high and low frequency input current filtering. A higher
filter cap value will result in lower low frequency input
current ripple, but with increased high frequency ripple.
The key at the FILTER node is that the capacitor has to be
very high frequency. If capacitor technology improves the
bandwidth, then higher values should be used. Similarly,
increasing the input capacitor value but decreasing its
resonant frequency will not really help. Decreasing it will
help the high frequency performance while increasing the
low frequency current ripple.
Direct Connection to Battery
Due to the ultra low input current ripple, it is possible to
connect the LTC3201 directly to the battery without using
regulators or high frequency chokes.
Flying Capacitor Selection
Warning: A polarized capacitor such as tantalum or alumi-
num should never be used for the flying capacitor since its
voltage can reverse upon start-up. Low ESR ceramic
capacitors should always be used for the flying capacitor.
The flying capacitor controls the strength of the charge
pump. In order to achieve the rated output current it is
necessary to have at least 0.22µF of capacitance for the
flying capacitor. Capacitors of different materials lose
their capacitance with higher temperature and voltage at
different rates. For example, a ceramic capacitor made of
X7R material will retain most of its capacitance from
– 40°C to 85°C whereas a Z5U and Y5V style capacitor will
lose considerable capacitance over that range. Z5U and
Y5V capacitors may also have a very strong voltage
coefficient causing them to lose 60% or more of their
capacitance when the rated voltage is applied. Therefore,
when comparing different capacitors it is often more
3201f

6 Page





ページ 合計 : 8 ページ
PDF
ダウンロード
[ LTC3201.PDF ]

共有リンク

Link :

おすすめデータシート

部品番号部品説明メーカ
LTC3200

There is a function of Regulated Charge Pump DC/DC Converters.

Linear Technology
Linear Technology
LTC3200-5

There is a function of Regulated Charge Pump DC/DC Converters.

Linear Technology
Linear Technology
LTC3201

There is a function of 100mA Ultralow Noise Charge Pump Led Supply.

Linear Technology Corporation
Linear Technology Corporation
LTC3202

There is a function of Low Noise/ High Efficiency Charge Pump for White LEDs.

Linear Technology
Linear Technology

多くを見つけるデータシート

部品番号部品説明メーカ
82S129

The 82S126 and 82S129 are field programmable, which means that custom patterns are immediately available by following the Signetics Generic fusing procedure. 1K-bit TTL Bipolar PROM, Address access time : 50ns max.

NXP
NXP
D1695

This part is a darlington connection NPN silicon epitaxial transistor. The 2SD1695 is a Darlington connection transistor and incorporates a dumper diode between the collector and emitter and a constant voltage diode and protection elements between the collector and base. This transistor is ideal for drives in solenoid and actuators.

NEC
NEC
FDMS86368

N-Channel Power Trench, 80V, 80A, 4.5mΩ.

Fairchild
Fairchild
2SC2456

Here is a Color TV Horizontal Driver, Vceo=300V, TO-126 Package.

Toshiba
Toshiba

www.DataSheet.jp    |   2018   |  メール    |   最新    |   Sitemap